EXPERIMENT NO -1BERNOULLIS THEOREM 1. Practical Significance: Learn application of Energy equation and understand how the various heads changes with change in cross sectional area of flow. Various heads involves are as follows Potential energy Pressure energy Kinetic energy P1 / W + V2 / 2g + Z1 = P2 / W + V2/ 2g + Z22. Competency Statement: Application of Bernoullis in conversion & diversion,Student should be able to analysis various of energy different flow geometry,3. Skill: 1. Learn pressure measurement by using piezometer . 2. Application of theoretical principle on real life situation 3. Team work ,critical thinking, problem solve,4. Experimental objective: To verify the Bernoullis equation using the Venturimeter (Law of Conservation Of Energy)5. Theoretical background:Bernoullis theorem is stated as in a steady continuous flow of a frictionless incompressible fluid, the sum of the Potential head, the pressure head & the Kinetic head is the same at all points.The present apparatus is a self contained unit operated on a closed circuit basis consisting of Sump Tank, collecting tank (delivery Tank), over head tank connected to Venturimeter with connections to Piezometer tubes at different sections. A constant steady supply of water by means of mono block pump-set with outlet delivery valve for flow control. There is also provision for measurement of flow rate thus the velocity.6. Experimental set-up: Bernoullis theorem apparatus
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8. Precautions: 1. Do not start pump set if the supply voltage is less than 180V (phase to phase voltage).1. Do not forget to give electrical earth & neutral connections correctly. 1. Initially, fill-in the tank with clean water free from foreign material. 1. At least every week, operate the unit for five minutes to prevent any clogging of the rotating and moving parts.1. To start and stop the supply pump, always keep valve open.1. It is recommended to put clean water to avoid scale formation on venturimeter.1. In case of any major faults, Please write to manufacture, and do not attempt to repair9. Procedure:1. Fill-in the Sump Tank with clean water.1. Keep the delivery valve open.1. Connect the power cable to 1 ph, 220V, 6 Amps with neutral and earth connections1. Switch-ON the pump. Now, you will find water flowing to the over head tank through venturimeter.1. Now, you find the different piezometric heads for corresponding points of venturimeter for constant supply head & delivery head.1. Note down all the pie zometric readings & pressure head at particular point is also noted separately by bringing the inserted probe to that point.1. Note down the time taken for height of water collected in the collecting tank provided downstream of the setup.1. Change the delivery head by pushing down the overflow pipe and repeat the experiment.1. Also, change flow of rate and repeat the experiment.10. Observation & calculation: Discharge measurement (Q) = Velocity of water (V) = Where A is the cross-sectional area of conduitVelocity head = V2/2gArea of collecting tank cm2 a = 430Discharge (Q)) Initial (h1 = cm Final (h2) = cm Time (t) = sec
TubeNo.Distance from inlet section(cm)Area of cross-section of conduitA (cm2)Velocity of flowV= Q/ACm/secVelocityHeadV2/2g(cm)PressureHeadp/w(cm)Datum headZ (cm)Total headp/w+ V2/2g+Z(cm)
1. 4.34.91
1. 5.33.57
1. 6.32.45
1. 7.31.42
1. 8.321.56
1. 9.621.75
1. 12.622.02
1. 15.322.79
1. 18.023.69
1. 20.724.71
11. Results:
12.Interpretation of results: Graph plot distance versus velocity head , pressure head ,total head.13 Conclusions.
14. Experiment related questions. 1. What do you mean by energy equation ? 2. What is total energy ? 3. How Bernoullis equation is different than see. 4. Why Perspex tube is used in the experiment. 5. What is effect of mass flow rate on velocity ? 6. How you calculate discharge. 7. Why actual discharge is different than theoretical, explain logical reason. 15. Assessment scheme:( a ) Team work. ( b ) process related.( c ) Conclusion. ( d ) Safety.(e) Would be done based on flowing measurable & Observable.
Experiment No: 02 ORIFICE EXPERIMENTS1. Practical Significance: Determine of Cd, Cc , Cv using different head method , to understand loss of energy and amplification of the same on the measurement & discharge or velocity,2. Competency statement : Apply basic law of conservation of mass & energy in case of flow through orifice. Calculate time of empty of tank & various coefficient like Cd, Cv, Cc. 3. Skill: 1. Interdependent learning. 2. Problem solving, critical thinking , Team work. 4. Experimental Objective: To determine the Coefficient of discharge Cd, Velocity Cv and Contraction Cc of various types of Orifices and Mouthpieces.5. Theoretical Background:An orifice is an opening in the wall of a tank, while a mouthpiece is a short pie fitted in the same opening. A mouthpiece will be running full if its length does not exceed two to three times the diameter. Both orifice and mouthpiece are used for discharge measurement. The jet approaching the orifice continues to converge beyond the orifice till the streamlines becomes parallel. This section of the jet is then a section of minimum area and is known as vena contracta.If Vc is the true horizontal velocity at the vena contracta, then the properties of jet trajectory give the following relationship: y = (g/2vc 2 ) x2 Vc = (gx2 /2y) 1/2 The theoretical velocity in the plane of the vena contracta V0 is given by
i.e. Vo =
Now coefficient of velocity C v =
C v = In which h is the constant head in the supply tank and x & y are coordinates of jet with respect to center of opening.
The actual discharge Q when divided by a yield the coefficient of discharge Cd . Here a is the area of cross-section of the orifice (or the mouthpiece) and g is the acceleration due to gravity. Once Cd and C v are known, the coefficient of contraction C c can be obtained by dividing Cd with C v
The coefficient of discharge can be also be computed by falling head method in which the supply is kept closed after filling the tank to a suitable level and fall in the head from h1 to h2 in time T is noted. The coefficient of discharge is then obtained from
Cd = [ h11/2 h21/2] 6. Experimental Set-up: Fig. Experimental setup for Orifice ExperimentsThe experimental setup consists of a supply tank with over flow arrangement and gauge glass tube for water level measurement in the tank. There is also provision for fixing the various orifices and mouthpieces (interchangeable) installed in the vertical plane of the tank Side. A set of orifice consisting of 10mm dia. and 15mm dia orifice is provided with the apparatus. Further a set of mouthpiece is also provided which consists of (i) 10mm dia x 25 mm length (ii)10mm dia x 40mm length (iii)10mm dia x 25mm x 25mm long divergent and (iv) 25 x 10 x 25 mm long convergent mouthpiece. Arrangement is made such that the water passes only through this attached opening. Water comes out of the opening in the form of jet.A horizontal scale on which is mounted a vertical scale with a hook gauge is attached to the supply tank. Thus hook gauge can be moved horizontally as well as vertically in x and y direction and its corresponding movement can be read on horizontal and vertical scales respectively. A collecting tank is used to find the actual discharge of water through the jet.7. Resource Required:Sr. noName of ItemSpecificationQuantityRemark
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8. Precautions: Discharge Apparatus should be in leveled conditions. Reading must be taken in steady or near by steady conditions. And it should be noted that water level in the inlet supply tank must be constant There should not be any air bubble in the piezometer. Orifice must be free from dirt and kept clean.9. Procedure:Step1: Note down the relevant dimensions as area of collecting tank and supply tank.Step2: attach a orifice/mouthpiece and note down its diameter.Step3: The water supply was admitted to the supply tank and conditions were allowed to steady to give a constant head. The lowest point of the orifice/mouthpiece is used as the datum for the measurement of h and y.Step4: The discharge flowing through the jet is recorded together with the water level in the supply tank.Step5: A series of readings of dimensions x and y was taken along the trajectory of the jet.Step6: The above procedure is repeated by means of flow control valve.Step7: The above procedure is repeated for other types of orifice/mouthpiece.10. Observation and calculation: Size and shape of the mouth piece/orifice = 1 cm Area of cross-section of mouth piece/orifice, a, cm2 = Area of cross-section of collecting tank, cm2 = 30 40Area of cross-section of supply tank, A, cm2 = 30 30Reading on the piezometer at the level on the center mouth piece/orifice h0 = 6 cm measurement Discharge (Q) =
Coefficient of discharge Cd = = where a is the cross-sectional area of orificeh is the reading in piezometer( in supply tank)
Coefficient of velocity C v =
C v = Cd = Cc X Cv
A CONSTANT HEAD METHOD:(i) Determination of Cd RunNo.Reading onThe piezometerA1(cm)Value ofh = A1-ho(cm)Discharge measurement Cd =
Initial (cm)Final(cm)Time(sec)Discharge Q(cm3/sec)
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04(ii) Determination of C v Reading of horizontal scale at exit of orifice/mouthpiece Xo =Reading of vertical scale at exit of orifice/mouthpiece Yo =RunNo.h(cm)X(cm)Y(cm)X= x- xo(cm)Y= y- yo(cm)C v =
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Average Cv = There for Cd = Cc X Cv 11. Result: Coefficient of discharge Cd = Coefficient of Velocity Cv = Coefficient of Contraction Cc =12.Interpretation of result:
13.Conclusion
14. Related short questions: 1. define coefficient of discharge Cd, velocity Cv and contraction Cc .2. what is the relation between Cd ,Cv and Cc ?3. why the value of these coefficients always remains less than one?4. what is called venacontracta?5. Among an orifice plate and venture meter, which apparatus provides more precised value of discharge and why?
15. Assessment scheme: (a) Process related. (b ) team work.(c ) conclusion. ( d ) safety.(e ) would be done based on flowing miserable & Observable.
Experiment No:-03REYNOLDS EXPERIMENT1. Practical significance: To analyses the flow through pipe and understood various flow like Laminar, turbulent,2. Competency statement: Application of energy equation in case of flow through pipe, Practical understanding of flow ...ion.3. Skill:1. Learn pressure measurement by using piezometer .2. Team work ,critical thinking, problem solve.4.Experimentel Objective:1. To study different flow conditions.2. To study the Reynolds number in different flow conditions.5. Theoretical background:Depending upon the relative magnitudes of viscous and inertial forces, flow can occur in to different manner viz. Laminar flow and turbulent flow. In laminar flow viscous effect are more predominant than the inertial effects. But when shear and normal stresses are added with the increase in velocity of flow the flow is turbulent. To identify the laminar and turbulent ranges of flow a dimensionless parameter is being utilizes which is a measure of the relative importance of inertial force and viscous force prevailing in the flow of a fluid, which is known as Reynolds number. It is equal to the ratio of the inertial force to the viscous force per unit volume. This 01mean that a large value of Reynoldss number signifies less viscous effects and vice versa. For determine the different flow conditions, equipment first used by Professor Osborne Reynolds after whose name Reynolds number (Re) exists.The motion is laminar or turbulent according as the value of Re is less then or greater then a certain value. If a liquid such as water is allowed to flow through glass tubes, if one of the liquid filaments is made visible by means of dye, then by watching this filament we may get insight in to the actual behavior of the liquid as it moves along.After the water in the supply tank has stood for several hour to allow to it to come completely to rest. The outlet valve is slightly opened. The central thread of dye carried along by the slow stream of water in the glass tube is seen to be nearly as steady and well defined as the indicating column in an alcohol thermometer. But when, as a result of further opening of the valve, the water velocity passes a specific limit, a change occurs, the rigid thread of dye begins to break up and to group momentarily ill-defined. The moment the dye deviates from its straight line pattern corresponds to the condition when the flow in the conduit is no longer in laminar conditions. The discharge, Q flowing in the conduit at this moment is measured and the Reynolds number=4Q/dv(in which d is the diameter of the conduit and v is the kinematics viscosity of water) is computed. This is the lower critical Reynolds number. Finally, at high velocities the dye mixes completely with the water and the colored mixture fills the tube
6. Experimental Set-up:
Reynolds Apparatus for Demonstration of Laminar& Turbulent Flow Apparatus consist of storage cum supply tank, which has the provision for supplying colored dye through je. A Perspex tube is provided to visualize the different flow condition. The entry of water in Perspex tube is through elliptical bell mouth to have Smooth flow at the entry. A regulating valve is provided on the down stream side of the tube to regulate the flow. The discharge must be varied very gradually from a smaller to larger value. A collecting is used to find the actual discharge through the Perspex tube
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8. Precautions:(i) Ensure the water in supply tank is clean. It should not be colored(ii) Regulate the flow slowly(iii) Take the observation only after the flow is established(iv) Do not release the potassium permagnate continuously, release only when you need to monitor the flow pattern 9. Experimental procedure:Step 1: Note down the relevant dimensions as diameter of Perspex tube, area of collecting tank and room temperature etc.Step 2: By maintaining suitable amount of steady flow in the Perspex tube, open inlet of the dye tank so that the dye stream moves as a straight line in the tube.Step 3: The discharge flowing in the Perspex tube is recorded.Step 4: This procedure is repeated for other values of discharge.Step 5: By increasing the velocity of flow in the Perspex tube, again open the inlet of the dye tank so that the dye stream begins to break up in the tube, which shows the fluid is no more in the laminar conditions .Hence transition stage accurse.Step 6: The discharge flowing in the Perspex tube is recoded.Step 7: This procedure is repeated for other values of discharge.Step 8: On further increase in the velocity of flow in the Perspex tube, again open the inlet of dye tank so that the dye mixes completely in the tube which shows fluid is no more the transition stage. Hence turbulent flow occurs in the tube.Step 9: The discharge flowing in the Perspex tube is recorded.Step 10: This procedure is repeated for other values of discharge.
10. Observation & calculation:Inner diameter of conduit D = 25 mmRoom temperature 0c =
Kinematic viscosity of water cm2/sec = 0.01Area of collecting tank, cm2 A =
Discharge Measurement
Sr. noInitial(cm)h1Final(cm)h2Time taken ( t)(sec)Discharge QCm3/sec
Reynolds No.
Re =
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Discharge measurement (Q) = Reynolds No .Re = where Q is discharge, D is diameter of conduit
is kinematic viscosity of water
11. Result: Reynoldss Number for laminar flow is = ----- Reynoldss number for Transition flow is = --- Reynolds,s number for Turbulent flow is = ------
12. Interpretation of result:
13. Conclusion:
14.Related short questions:1. Define the raynolds number.2. What is range of raynolds number for turbulent and laminar flow?3. What is called a critical reynolds number ? What is its value for the laminar flow?4. The equations of motion for laminar flow of a real fluid are known as.5. In which type of flow, the viscous forces are dominant? 15.Assessment scheme: (a) process related ( b) safety( c ) Conclusion ( d ) Team work (e) would be done based on flowing measurable & Observable
Experiment No: 04 RECTANGULAR AND V- NOTCH1. Practical Significance: Calibration of rectangular and v- notch, It in part understanding of calibration of flow measurement devices, 2.Competency statement: Notch apparatus to calibrate rectangular and v- notch.3.Skill: 1. Interdependent learning , 2 Problem solving, critical thinking , Team work. 4.Experimental Object: Determination of discharge coefficients of: V- Notch ( V ) Rectangular notch ( U )5.Theoritical background Different types of models are available to find discharge in an open channel as notch, venturiflume, weir etc. For calibration of rectangular notch, trapezoidal notch or V notch some flow is allowed in the flume. Once the flow becomes steady, uniform discharge coefficients can be determined for any notch.In general sharp crested notches are preferred where highly accurate discharge measurements are required. For example in hydraulic laboratories, industry and irrigation pilot schemes, which do not carry debris and sediments.Notches are those overflow structures whose length of crest in the direction of flow is accurately shaped. They may be rectangular, trapezoidal, V notch etc. The V- notch is one of the post precise discharge-measuring devices suitable far a wide range of flow. Making the flowing assumptions as to the flow behavior can develop the relationship between discharge and head over the weir.(a) Upstream of the weir, the flow is uniform and the pressure varies with depth According to the hydrostatic equation p = gh (b) The free surface remains horizontal as far as the plane of the weir, and all Particles passing over the weir move horizontally.(c) The pressure through out the sheet of liquid or nape, which passes over the Crest of the weir, is atmospheric. The effect of viscosity and surface tension are negligible.(d) The velocity in the approach channel is negligible.A triangular or V notch is having a triangular or V shaped opening provided in its body so that water is discharged through this opening only. The line which bisects the angle of the notch should be vertical and at the same distance from both side of the channel. The discharge coefficient Cd of V notch may be determined by applying formula.
Where Q is the discharge over a triangular notch, is the apex angle of notch and H is the head over the crest of the notch. A rectangular notch, symmetrically located in a vertical thin plate, which is placed perpendicular to sides and bottom of a straight channel, is defined as rectangular sharp crested weir. The discharge coefficient Cd of a rectangular notch may be determined by applying formula. Where Q is the discharge over a rectangular notch, B is the width of notch, H is the head The crest of the notch and g is acceleration due to gravity
6. EXPERIMENTAL SET-UP: The experimental set up consists of a tank whose inlet section is provided with two Nos. of baffles for streamline flow. While at the downstream portion of the tank one can fix a notch of either rectangular or V- notch. A point gauge is used to measure the head of water over the model A collecting is used to fined the actual discharge through the notch7. Resources RequiredS.r noName of ItemSpecificationQuantityRemark
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8. Precautions: Reading must be taken in steady state or near steady conditions. For the measurement of correct discharge there must not be any leakage near the notch and take care that notch is not running in overflow conditions. For measurement of correct head over the notch the point gauge must be installed little distance away from the crest of the notch. Discharge must be varied very gradually from a higher value to smaller values. 9. Procedure: Step 1: The notch under test was positioned at the end of the tank, in a vertical plane, and with the sharp edge on the upstream side.Step 2: The tank was filled with water up to the crest level and subsequently note down the crest level of the notch by the help of a point gauge.Step 3: The flow-regulating valve was adjusted to give the maximum possible discharge without flooding the notch.Step 4: Conditions were allowed to steady before the rate of discharge and head H were recorded.Step 5: The flow rate is reduced in stage and the readings of discharge and H were taken.Step 6: The above procedure is repeated for other type of notches. 10. Observation & Calculation:Discharge measurement (Q) = The discharge coefficient Cd of V notch may be determined by applying formula Where Q is the discharge over a triangular notch, is the apex angle of notch and H is the head over the crest of the notch. The discharge coefficient Cd of a rectangular notch may be determined by applying formula. Where Q is the discharge over a rectangular notch, B is the width of notch, H is the head the crest of the notch and g is acceleration due to gravity. (a) Triangular or V notch Apex angle of notch, = 90 Crest level of V notch H1, cm = Area of collecting tank, a ,cm2 =
Sr.No.Discharge measurementHead over notch H=H1-H2Cm
Initialh1 cmFinalh2 cmTimeSecondDischargeQ(cm3/sec)
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Average Cd =(b) Rectangular notch Width of notch cm = 12.0 Crest level of notch,H1 cm = Area of collecting tank, a cm2 =Sl.No.Discharge measurementHead over notch H=H1-H2Cm
Initialh1 cmFinalh2 cmTime(t)SecondDischarge Q(cm3/sec)
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Calculate discharge (Q) and coefficient of discharge Cd for V-notch and rectangular notch 11. Result: Coefficient of discharge of V-notch is = Coefficient of discharge of Rectangular-notch is =12.Interpretation of Result: Graph plot Q versus Hon a log- log paper with Q is ordinate. Draw a best fit straight line to the data point
13. Conclusion:
14.Related short question: 1. If the head measurement error 1%, then how much error will occur in discharge?2. What do you mean by calibration of V-noch and rectangular notch?3. What is difference between notch and weir?15. Assessment scheme:(a) process related. (b) safety.( c ) Conclusion. ( d ) Team work. (e) would be done based on flowing measurable & Observable.
Experiment No: 05DARCYS LAW 1.Practical Signification: Analysis flow of fluid through porous medium, Similar situation in flow of crud oil through petroleum reservoir. 2. Competency Statement:Determination of coefficient of permeability of pours medium,Application of log log graph paper plot nonlinear behavior of velocity and hydraulic gradient3. Skill: 1. Learn pressure measurement by using piezometer . 2. Application of theoretical principle on real life situation. 3. Team work ,critical thinking, problem solve.4. Experimental Objective:To verify Darcys law and to find out the coefficient of permeability of the given medium. 5. theoretical background: The flow of a fluid through a porous medium follows, under certain limitations, Darcys law. Darcys law status When a fluid flows trough a porous medium, the apparent mean velocity of flow is proportional to the gradient i.e. hf/L, where hf is the head loss between the two sections which areL apart. This means, V = ki -------------- (1) Where V is the mean apparent velocity which is equal to the rate of discharge divided by the area of cross section of the sand mass perpendicular to the flow direction (note that actual area of flow cross-section is smaller then the area of sand mass perpendicular to the flow), K is the constant of proportionality termed as the coefficient of permeability and i (hf/L) is the hydraulic gradient.This law is valid when inertial forces are less than the viscous forces. In general, the law is considered as valid when the Reynolds number (defined as Vd/v, where d is the average diameter of the sand grains) is less than unity. Beyond Darcys range (i.e. Reynolds number greater than unity) the mean velocity is given by V = Kin (2)Where the index n is greater then unity.It is obvious that velocity and hydraulic gradient are measured for small velocities of flow (i.e. Reynolds number, less than unity and plotted on a log-log graph paper, the resulting plot will be a straight line inclined at an angle of 450 (i.e. slope equal to unity). Beyond this range the resulting straight line will have a steeper slope.6. EXPERIMENTAL SET-UP:The experimental setup consists of a perspex column of size 6.9cm X 100cm. The column is filled with sand grains of uniform size (about 2.0mm diameter). Six pressure points are provided on one side of the column. These pressure points are connected to piezometer tubes connected to a manometer. This supply pipe is connected to the lower end of the column. Outlet pipe is connected to the upper end of the column. Mesh is provided to prevent the migration of sand grains along with the flow. Discharge of water can be collected by the help of a collecting tank.
Fig: Flow through sand
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8.Precaution: Remove all entrapped air from the piezometer tubes of manometer. Maintain constant discharge for one set. Take a number of readings to obtain accurate result. All the readings should be taken carefully during the experiment to reduce the error.9. Procedure:Step 1: Open the inlet flow control valve to allow a steady flow through the vertical column. Check If there is any air bubble in the manometer tube. If so remove the same.Step 2: By maintaining suitable amount of steady flow in the vertical column, there establishes a Steady none-uniform flow in the circuit. Time is allowed to stabilize the levels in the manometer tube.Step3: The discharge flowing in the circuit is recorded together with the water levels in each Piezometer tube.Step 4: The flow rate is reduced in stages by means of flow control valve and the discharge & readings of manometer are recorded.
10. Observation & Calculation: Discharge measurement (Q) = V = ki Where V is apparent velocity and I is hydraulic gradient and K is coefficient of permeability , V= Q/A cm/sec and I = hf/L hf is head loss between two points and L is distance between two points Sand grain diameter, d mm Diameter of vertical column, D cm = 6.9 Area of column, A cm2 = D2 Area of collecting tank, a cm2 = S No.
Discharge Measurement
ApparentMean Velocity
V =Cm/secPiezometer Readings
UnitInitial(cm)
Final(cm)Time(sec)DischargeQ(cm3/sec)123456Mean Value of i as obtainedFrom the graph
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I -fill up the data sheet.II- Calculate the discharge, difference of manometer reading and Cd for different given sand mass is sets of readings.III- Plot the piezometer reading (on Y-axes)v/s distance of the corresponding pressure points from the selected reference points for each of the runs taken. Fit in a straight line for each of these runs and find the slope of each of these lines. These are the mean values of i (hf/L) for different runs. Enter these values of i in the last column of the observations and computations table. Also calculate the velocity V for all these runs.IV- Plot V v/s i (with I on x- axes) on a log-log graph paper. Fit in a straight line having unit slop to data points for relatively low velocity. For higher velocity data points, fit in another straight line with different slope. This is verification of Darcys law.Select any point on V v/s I line for small velocity data points and find its coordinates i.e V and i. Determine k using equation(1). Thus the coefficient of permeability of K = V/ i V- Determine the value of n from V = kin from V v/s i line fir higher velocity data points. VI- determine the value of n from V = Kin from V v/s i line for higher velocity data points.Position of piezometer points from the reference point (screen)Piezometer point123456
Distance for reference point(screen)cm11631466176
11. Result: Coefficient of permeability of given medium is =
12.Interpretion of results: Graph plot v versus I on log-log graph paper.13. Conclusion:
14.Short Questions:1. What is darcy weisbach equation?2. How to relate friction factor in laminar flow with Reynolds number?3. What is apparent mean velocity?4. Define permeability?5. Why log-log paper is used in this experiment?15. Assessment scheme:(a) process related (b) conclusion (c) Safety (d) Teamwork (e) would be done based on flowing measurable & Observable.
Experiment No: 06 MOMENTUM EQUAVATION1. Practical Significance: Develop basis understanding of momentum principal in hydraulic machinery like hydraulic turbine.2.Competency Statement: Student should be able to apply momentum equation on horizontal and curved vane.3.Skill: 1. practical understanding of momentum equation. 2. Application of theoretical principle on real life situation. 3. Team work ,critical thinking, problem solve.4.Experimental OBJECTIVE:1. To verify the momentum equation experimentally. 2. Comparison of change in force exerted due to shape of the vane for different targets.5.Theortical background:Momentum equation is based on Newtons second law of motion which states that the algebraic sum of external forces applied to control volume of fluid in any direction is equal to the rate of change of momentum in that direction. The external forces include the components of the weight of the fluid and of the forces exerted externally upon the boundary surface of the control volume. If a vertical water jet moving with velocity V is made to strike a target, which is free to move in the vertical direction, the a force will be exerted on the target by the impact of jet. According to momentum equation this force (which is also equal to the force required to bring back the target in its original position) must be equal to the rate of change of momentum of the jet flow in that direction.
Applying momentum equation in X direction -Fx = Q [ Vx.out -Vx.in] = Q [V Cos - V] Fx = QV [1- Cos] For flat plate, = 900 Fx = QV For hemispherical cup, = 1800 Fx = 2 QV Here , p is the mass density, Q is the discharge through the nozzle, V is the velocity at the exit of nozzle (i.e. Q/A) and a is the area of cross section of nozzle. Fx = Q2/a While for curved hemispherical vane the force is Fx = 2Q2/a6. Experimental Set- UP:The Experimental setup primarily consists of a nozzle through which a water jet emerges vertically in such a way that it may be conveniently observed through the transparent cylinder. It strikes the target vane positioned above it. The force applied on the vane by jet can be measured by applying weight to counteract the reaction of the jet. Vanes are interchangeable i.e. flat or curved.Arrangement is made for the movement of the plate under the action of the jet and also because of the weight placed on the loading pan. A scale is provided for carrying the vanes to its original position I,e. as before the jet strikes the vane. A collecting tank is used find the actual discharge and velocity through the nozzle.
Fig: Impact of jet Apparatus7. Resources Required:S.rNoName of Item Specification QuantityRemark
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8.Precautions: Apparatus should be in leveled condition. Reading must be taken in steady or near by steady condition. Discharge must be varied very gradually from a higher to smaller value.9. Procedure:Step 1: Note down the relevant dimension as area of collecting tank, mass density of water and dia of nozzle.Step 2: The flat plate is installed.Step 3: When jet is not running, note down the position of upper disc.Step 4: The water supply is admitted to the nozzle and the flow rate adjusted to its maximum value.Step 5: As the jet strikes the vane, position of upper disc is changed. Now place the weights to bring Back the upper disc to its original position.Step 6: At this position find out the discharge as well as note down the weights placed on the upper Disc.Step 7: The procedure is repeated with the installation of curved vane in the apparatus.10. Observation & calculation: Discharge measurement (Q) = mass density of water () = 1 gm/cm3 Dia of nozzle is = 1.0 cm Cross-sectional area of nozzle a = d2 For hemispherical cup, = 1800 Fx = 2 QV Here , is the mass density, Q is the discharge through the nozzle, V is the velocity at the exit of nozzle (i.e. Q/A) and a is the area of cross section of nozzle. Fx = Q2/a While for curved hemispherical vane the force is Fx = 2Q2/aDia of nozzle, d , cm = 1.0
Mass density of Water , gm/cm3 =
Area of collecting tank cm2 = Area of nozzle, a = d2
Horizontal flat vane: When jet is not running, position of upper disc =RunNo.Discharge MeasurementBalancingTheoreticalForceFQ2/ a(dyne)Error in%F-F/ F
Initial(cm)
Final(cm)Time(sec)Discharge(Cm3/sec)QMassm(gm)ForceF(dyne)
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Curved vane: When jet is not running, position of upper disc =RunNo.Discharge MeasurementBalancingTheoreticalForceF2Q2/a(dyne)Error in%F-F/F
Initial(cm)
Final(cm)Time(sec)Discharge(Cm3/sec)QMassm(gm)ForceF(dyne)
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For hemispherical cup, = 1800 Fx = 2 QV Here , is the mass density, Q is the discharge through the nozzle, V is the velocity at the exit of nozzle (i.e. Q/A) and a is the area of cross section of nozzle. Fx = Q2/a While for curved hemispherical vane the force is Fx = 2Q2/11. Result: Percentage error for flat vane is = % Percentage error for curved vane is = %12. Interpretation of result:
13. Conclusion:
14. Related short question:1. What is momentum theorem ? it based upon which conservation principal?2. Explain why force on hemispherical vanes is double than the flat vanes?3. What is the maximum hight of free jet, if it is issued vertically?4. What is casuse of error between the theoretical and actual force?15. Assessment scheme:(a) Process Related (b) conclusion(b) safety ( d ) Team work (e) would be done based on flowing measurable & Observable.
Experiment No.-07 PIPE FRICTION 1. Practical Significance:This experiment helps students to understand role of viscous action in flow through pipes. It provide basis of measuring frictional pressures drop and how does the friction factor varies with change in diameter and material of the pipe. 2.Competency Statement:Determination of friction factor Comparing experimental observations with the corresponding value obtained from Darcys friction factor plot. Rest will be same 3.skill: 1. Learn pressure difference measurement by using U tube manometer . 2. Application of theoretical principle on real life situation. 3. Team work ,critical thinking, problem solve.4. Experimental Objectives:To study the variation of the friction factor, f, with the Reynolds Number, Re, for flow of fluids in rough and smooth circular commercial pipes.5. Theoretical Background:When a liquid flows through a pipe with a pressure driving force, head is lost in overcoming the viscous friction in the flowing liquid. This frictional resistance for flow from point, 1, to point, 2 (locations of the two pressure taps), in a circular, horizontal, uniform-diameter pipe with no pump/turbine in-between the pressure taps and with no fittings in-between points 1 and 2, is described by the following form of the macroscopic energy balance (engineering Bernoulli equation): (7.1)In Eq. 7.1, f is the friction factor (a dimensionless quantity), L is the length of the pipe between the two pressure taps (points, 1 and 2), Vp is the average velocity of flow in the pipe (), Q (m3/s) is the volumetric flow rate in the pipe of (actual internal) diameter, Dp, and are the density and dynamic viscosity of the fluid flowing, g is the acceleration due to gravity and pi is the pressure at point, i. The Darcys friction factor, f, is a function of the Reynolds Number, Re () and the roughness factor, /Dp, as shown in Fig. 7.1. The values of for a commercial steel pipe and a copper/brass pipe are: 0.046 10-3 m and 0.0015 10-3 m, respectively. 6. Experimental Set-up:The apparatus consists of a pipe circuit in which flow of water takes place in four commercial, Schedule 40, steel pipes (galvanized iron on the outside) having different (nominal) diameters: 15 mm, 20 mm, 25 mm, and 32 mm, at different flow rates. The fifth pipe is smooth, made of copper/brass, having a nominal diameter of 25 mm. Each pipe is provided with two pressure taps, a certain distance apart. A U-tube manometer is provided to find the p (pressure drop) between the points used for the pressure taps. The pressure taps are connected to a manometer, turn by turn. The discharge, Q m3/s, of water through the pipes can be measured easily at different openings of the valve in the circuit, as can be the corresponding p.7.Resource Required:S.R NOName OF item SpecificationQuantityRemark
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8.Precautions: Maintain the steady flow Take the reading when steady condition acure. Do not open control valve fast. Remove air bubble in the U tube manometer.9.Procedure:Step 1: Note down the relevant dimension as diameter of pipe, length of pipe between the Pressure tapings, area of collecting tank etc.Step 2: Pressure tapings of a pipe are kept open while for other pipes it is kept closed.Step 3: Open the inlet flow control valve and regulate the valve to allow a steady flow through the pipe. Check if there is any air bubble in the manometer tube. If so remove it.Step 4: The flow rate was adjusted to its maximum value. By maintaining suitable amount of steady flow or near by steady flow in the pipe circuit, there establishes a steady non-uniform flow in the circuit. Time is allowed to stabilize the levels in the manometer tubes.Step 5: The discharge flowing in the circuit is recorded together with the water level in left and right limbs of Manometer tubes.Step 6: The flow rate is reduced in stages by means of flow control valve and the discharge &readings of manometer are recorded.Step 7: This procedure is repeated by closing the pressure tapings of this pipe and for opening of another pipe10 .Observation & calculations: The generally accepted formula governing turbulent flow in pipes may be summarized as follows by Darcy-Weisbach formula for head loss due to friction hf = flv2/2gD hf = 8fL Q2/2gD5 Where f is known as friction factor which is a dimensionless quantity, L is length of pipe, V is mean velocity of flow in pipe, Q is discharge through pipe, g is acceleration due to gravity and D is diameter of pipe.Material of pipe =Diameter of pipe D =Length of pipe between two pressure tapping L cm = 240 cmArea of collecting tank a cm2 = Temperature of water, 0 C = Kinematics viscosity of water v m2/sec = Discharge measurement (Q) = = ?
02S.NoManometer readings
Discharge measurement
hf=8fLQ2/2gD5
DiameterOf PipeD
3.2 (G.I)Left limbh1(cm)Right limb h2(cm)Difference of head in terms of water hf12.6(h1-h2)Initial(cm)Final(cm)Time(sec)DischargeQ(cm3/sec)
2.5 (G.I)
1.9 (G.I)
1.2 (G.I)
2.5(BRASS)
Fill up the data sheet. Calculate the discharge, difference of manometer reading and f friction factor for different pipes for different sets of readings, Find the average friction factor f. The observation shows that the coefficient f is not a constant but its value depends on the roughness condition of the pipe surface and the Reynolds number of the flow.11.Results: friction factor of (G.I) pipe dia 3.2 cm is = Friction factor of (G.I) pipe dia 2.5 cm is =Friction factor of (G.I) pipe dia 1.9 cm is =Friction factor of (G.I) pipe dia 1.2 cm is = Friction factor of (copper) pipe dia 2.5 cm is =12. Interpretation of ResultPlot a graph between the Reynolds no versus the friction factor with f1 is ordinate.Compare the result with the standard curve (Moodys diagram )13.Conclusion:
14.Related short questions:1. Define the friction factor. Is there any other friction factor than Darcys friction factor?2. What are the extra energy losses (in fittings) for flow through pipe networks?4. Explain why the friction factor, f, depends only on Re for some ranges of Re, while it depends on two dimensionless parameters for other ranges of Re.5. How does the material of the pipe affect the pressure loss due to friction?6. Deduce how the pressure drop is related (exponent) to the velocity in the pipe for low Re, and for very large Re. 3. Define the surface roughness, .
Fig. 7.1: Darcys friction factor plot (Fig. 10.3 in V. Gupta and S. K. Gupta, Fluid Mechanics and its Applications, 3rd Ed., New Age International, New Delhi, 2015)15.Assessment Scheme:(a) Process Related(b) Conclusion(c) Safety (d) Team work (e) would be done based on flowing measurable & ObservableExperiment N0. 08 LOSSES IN PIPE FITTINGS1.Practical Significance:It develop understating of minor losses in pipe flow, also helps to compare minor losses in different geometry change. 2. competency Statement:Students should be able to determine loss coefficient for different fittings. They should compare loss coefficient for elbow and bends, sudden expansion and sudden contraction. 3. Skill: 1. Learn pressure difference measurement by using U tube manometer . 2. Application of theoretical principle on real life situation. 3. Team work ,critical thinking, problem solve. 4. Experimental Objective: To determine the minor head loss coefficient for different pipe fittings.5. Theoretical Background:In pipe networks, the major loss of mechanical energy is associated with straight-length pipes, while minor losses are associated with pipe fittings. The latter are caused by changes in the velocity of the flowing fluid (magnitude or direction). Losses due to changes in cross-section, bends, valves and fittings of all types are categorized as minor losses. At times, the losses in the fittings may even outweigh the friction losses in straight-length pipes.The macroscopic energy balance (engineering Bernoulli equation) between an upstream point, 1, and a downstream point, 2, can be written as (for flow of the same liquid of density, ) (8.1)In Eq. 7.1, f is the friction factor (a dimensionless quantity), L is the length of the straight-length pipe between the two points, 1 and 2, Vp is the average velocity of flow in the straight-length pipe (), Q (m3/s) is the volumetric flow rate in the pipe of (actual internal) diameter, Dp, and are the density and dynamic viscosity of the fluid flowing, g is the acceleration due to gravity and pi is the pressure at point, i. The frictional losses in the straight-length pipes are to be added for the several sections (possibly of different diameters), if necessary. The Darcys friction factor, f, is a function of the Reynolds Number, Re () and the roughness factor, /Dp, in each section of the straight-length pipe. Ki is the friction loss coefficient in the ith fitting between points 1 and 2, again to be added for each fitting between points 1 and 2. The last term in Eq. 8.1 can also be written in terms of the head-loss factor, hL,i, for the ith fitting as (8.2)Ki depends on the detailed flow inside the fitting, and is normally a function of the Reynolds number in the straight-length pipe associated with the fitting, attaining an asymptotic value at high Re. However, this conservative asymptotic value of Ki is used in pipeline design (and this value is available for various fittings in textbooks). For sudden enlargement of the cross-section, the simultaneous application of the continuity, Bernoulli and momentum equations shows than where VS and VL are the mean velocities of flow in the smaller and larger diameter pipes at the two ends of the expansion, respectively.6. EXPERIMENTAL SET-UP:The experimental set-up consists of a pipe network with straight-length pipe of diameter 25 mm with the following pipe fittings and with valves to vary the flow rate: Large bend Sudden enlargement from the pipe diameter to 50 mm diameter Small bend Sudden contraction from 50 mm diameter to 25 mm diameter Pressure taps are provided on the up-stream and down-stream ends of each of the fittings to enable the measurement of the pressure difference, p, across the fittings at different flow rates, Q. The pressure taps are connected to a differential manometer. A collecting tank is used to estimate Q.
7. Resource Required:S.r noName of ItemSpecificationQuantityRemark
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8.precaution: Apparatus should be leveled (made horizontal) initially. Readings must be taken under steady conditions. There should be no air bubble trapped in the manometer.9. Experimental procedure:Step 1: Exist valve is fully open.Step 2:The pressure taps of the pipe fitting being studied are kept open while those for all the other fittings are kept closed.Step 3:The flow rate through this fitting is adjusted to its maximum value.Step 4:Time is allowed to stabilize the levels in the two limbs of the manometer.Step 5:The flow rate, Q, of the water in this circuit is measured as also the manometer reading.Step 6:This is repeated at a few more (lower) values of Q, as well as for the other fittings8.Observation & Calculation:Table -1 Type of fitting: Large bend and small bend Diameter of bend pipe d = 2.5 cm Cross-sectional area of bend pipe a = d2
RunNo.Manometer readingsDischarge Measurement
Left limbh2(cm)Right limbh2(cm)Difference of head in terms of water hL=12.6(h1-h2)CmInitial(cm)Final(cm)Time(sec)DischargeQ Cm3/secV=Q/aCm/secLossCoefficient k=2ghL/V2
1
2
3
4
Table-2Type of fitting: Sudden enlargement and sudden contractionDiameter of smaller pipe cm d = 2.5Area of smaller pipe, a cm = d2Diameter of bigger pipe cm d1 = 5.0Area of bigger pipe a1 cm2 = (d1)2 Area of collecting tank, A cm2 = RunNo.Manometer ReadingsDischarge Measurement
LeftLimbh1(cm)Right LimbH2(cm)Difference of head in terms of water hL=12.6(h1-h2)(cm)Initial(cm)Final(cm)Time(sec)DischargeQ(cm3/sec)V= Q/a(Cm/sec)V1=Q/a1Loss coefficient k=
1.
2.
3
4
for large and small bed : Velocity of flow V=Q/a cm/sec Loss Coefficient k=2ghL/V2 Average loss coefficient, k =For sudden enlargement and sudden contraction: Velocity of flow in small pipe dia V=Q/a cm/sec Velocity of flow in large pipe dia V1=Q/a1 cm/sec Loss coefficient k= 11. Results: Loss coefficient k in small bend is = Loss coefficient k in large bend is = Loss coefficient k in sudden enlargement bend is = Loss coefficient k in sudden contraction = 12. Interpretation of Result:
13. Conclusion:
14. Related short questions:1. What is minor loss?2. Explain dependency of large diameter pipe in case of sudden contraction loss.3. How you can reduce entrance loss?4. Which one is more suitable for changing the flow direction ? Elbows or bends?5. In case of reducer how angle of cone affects m 15. Assessment of Scheme: (a) Process related (b) conclusion(c) safety (d) Team work (e) would be done based on flowing measurable & Observable. Experiment No:-09FLOW MEASUREMENT APPARATUS1.Practical Signification: It provides insight of flow measurements in internal flow. In industrial practice flow measurement is important aspect to take necessary decision. 2.Competency Statement:1. To calibrate a venture & Orifice meter and to study the variation of its coefficient of discharge with the Reynolds number3.Skill: 1. Learn pressure difference measurement by using U tube manometer . 2. Team work, critical thinking, problem solve. 3. Application of venturimeter & orifice meter.4. Experimental OBJECTIVE: 1. To calibrate a venture meter and to study the variation of its coefficient of discharge with the Reynolds number 2.To calibrate an orifice meter and study the variation of its coefficient of discharge with the Reynolds number5. theoretical background:The venturi and orifice meters are devices used for the measurement of the flow rate of the fluid (here, water) flowing in a pipe. The basic principle on which these meters work is that by reducing the cross-sectional area of the flow passage, a pressure difference is created and the measurement of this pressure difference enables the determination of the discharge through the pipe.
Fig. 9.1: Schematic of a venturi meter
A venturi meter consists of an inlet section (1) followed by a convergent cone, (2), a cylindrical throat and a gradually divergent cone (3). Since the cross-sectional area of the throat is smaller than the cross-sectional area of the inlet section, the velocity of flow at the throat is higher than in the inlet section (continuity equation). The increase in the velocity of flow at the throat results in a decrease in the pressure at this section (Bernoulli equation). The pressure difference is determined using a U-tube manometer between the two pressure taps provided. This pressure difference enables one to calculate the flow rate (Q) of the fluid in the pipe using where a0 is the area of cross-section of the throat (diameter, d0), a1 is the area of cross-section of the pipe (diameter, D or d1), g is the acceleration due to gravity, hm is the manometer reading, Hg and f are the densities of mercury and the flowing fluid (water), and Cd is the coefficient of discharge of the venturi meter.
The venture-coefficient, Cd, accounts for viscous losses and depends upon the Reynolds number (at the throat), Re0 (which is equal to V0d0/, where V0 = Q/a0 and d0 is the diameter of the throat), and the ratio d0/D. For the given experimental set-up, d0/D is fixed. Usually, Cd varies between 0.96 and 0.99 for the throat-Reynolds numbers above about 105.
An orifice meter is a cheaper arrangement for the measurement of the discharge through pipes and its installation requires a smaller length as compared to other flow measuring devices, like the venture meter (or a flow nozzle). An orifice meter consists of a flat circular plate with a circular hole, called the orifice, which is concentric with the pipe axis, as shown in Fig. 2. The orifice is not of constant diameter but makes an angle of about 30-45 with the axis. The orifice Fig. 9.2: Schematic of an orifice meterplate is clamped between two pipe flanges. Two pressure taps are provided at points 1 and 2 (in Fig. 2), one on the upstream side of the orifice plate and the other on the downstream side of the orifice plate (about one-half the pipe diameter from the orifice). A pressure difference is created between the two taps, which is measured using a U-tube mercury-water manometer. The discharge coefficient can be calculated using formula. Here, Cd is the orifice coefficient, a0 is the cross-sectional area of the orifice, a1 is the cross-sectional area of the pipe, g is the acceleration due to gravity and hm is the manometer reading. The value of Cd, in general, depends on the d0/d1, location of the pressure taps (1) and (2), and the orifice-Reynolds number, Re0. Since the first three parameters are fixed in the experimental set-up in the laboratory, Cd can be said to depend only on the Re0, defined as V0d0/f where V0 is the velocity of flow at the orifice (Q/a0). It should be noted that Cd attains a constant value at higher values of Re0 (higher than about 10 5).6. EXPERIMENTAL SET-UP:The experimental set-up consists of a flow circuit having two parallel paths. The two parallel pipelines are of diameter 25 mm each. One path incorporates a venturi meter while the other has an orifice meter. Both the venturi meter and the orifice meter have d/D = 0.6 and both have two pressure taps each, one upstream and the other downstream (throat or orifice) of the meter. A U- tube water-mercury manometer is provided to measure the pressure difference between the two pressure taps for the venturi meter and the orifice meter. A regulating valve is provided on the downstream side of each pipe to regulate the flow rate of the water. Water is collected in a tank for a specified period of time, and this information is used to find the actual discharge rate through the circuit.
7.Resource required:S.r noName Of ItemSpecification QuantityRemark
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8. Precaution: Remove all entrapped air from the two limbs of the manometers. Maintain steady state conditions for each run. Take a number of readings for the same flow rates to obtain accurate results.
9. Procedure:Step1: Note down the relevant dimension as diameter of the pipe, diameter of orifice/throat, area Of collecting tank, room temperature etc. Step2: Regulating valve of a pipeline is kept open while for other it is closed.Step3: Pressure tapings of a venturimeter are kept open while for orifice meter are kept closedStep4: Open the inlet flow control valve and regulate the valve to allow a steady flow through the pipe. Check if there is any air bubble in the manometer tube. If so remove the same.Step5: The flow rate was adjusted to its maximum value. By maintaining suitable amount of Steady flow or near by steady flow in the pipe circuit, there establishes a steady none uniform flow in the circuit. Time is allowed to stabilize the levels in the manometer tube.Step6: The discharge flowing in the circuit is recorded together with the water levels in left and right limbs of manometer tube.Step7: The flow rate is reduced in stages by means of flow control valve and the discharge & readings of manometer are recorded for every stage.
MEASUREMENT OF FLOW BY ORIFICEMETER Step 8: pressure tapings of a orifice meter are kept open while for venturimeter are kept closed.Step 9: Open the inlet flow control valve and regulate the valve to allow a steady flow through the pipe. Check if there is any air bubble in the manometer tube. If so remove the same.Step10: The flow rate was adjusted to its maximum value. By maintaining suitable amount of steady flow or near by steady flow in the pipe circuit, there establishes a steady non-uniform flow in the circuit. Time is allowed to stabilize the levels in the manometer tube.Step11: The discharge flowing in the circuit is recorded together with the water levels in left and and right limbs of manometer tube.Step12: The flow rate is reduced in stages by means of flow control valve and the discharge & Readings of manometer are recorded for
10. Observation & Calculation:for venturimeter Where a is the area of cross-section of throat, a is the area of cross-section of inlet, g is The acceleration due to gravity, h is the difference of head in terms of water and C d is The coefficient of discharge of venturimeter.Where Cd is coefficient of orifice, a0 is cross-sectional area of orifice,a1 is cross-sectional area of pie, g is the acceleration due to gravity and h is the difference of head in terms of water. Observation: Type of flow meter = Venturimeter Diameter of pipe line D cm = 2.5
Cross-sectional area of the pipe line Acm2 = D 2 Diameter of throat/orifice sectiond cm (d/D=0.6) = 1.5
Cross-sectional area of throat/orifice section, cm2 = d2 Area of collecting tank cm2 = Temperature of water, 0C =
Kinematics viscosity of water cm2/sec =
RunNo.Discharge measurementManometer ReadingCdRe=Qd
a
Initial(cm)Final(cm)Time(sec)Discharge Q(Cm3/sec)Left limbh1(cm)Right limbh2(cm)Diff. ofHeadh=12.6(h1- h2) (cm)CalculateBy usingFormula
1
2
3
4
5
Type of flow meter = Orifice meter Diameter of pipe line d1 cm = 2.5
Cross-sectional area of the pipe line a1cm2 = d1 2 Diameter of throat/orifice sectiond0 cm (d/D=0.6) = 1.5
Cross-sectional area of throat/orifice section, a0 cm2 = d02 Area of collecting tank cm2 =
RunNo.Discharge measurementManometer ReadingCdRe=Q d0
a
Initial(cm)Final(cm)Time(sec)DischargeQ(Cm3/sec)Left limbh1(cm)Right limbh2(cm)Diff. of Headh=12.6(h1-h2) (cm)
1
2
3
4
calculate the coefficient of discharge for venturimeter and orificemeter11. Result: average coefficient of discharge of venturimeter is = Average coefficient of discharge of orificemeter is =12.Interpretation of results: Graph draw1. Plot Q v/s h on a log- log graph paper and fit in a straight line for the plotted points. This is the calibration curve.2. Plot Cd v/s Re for the observed data.
13.Conclusion:
14. Related short questions:1. Derive the meter equations from first principles.1. Define the coefficient of discharge, CD.1. Why is CD higher for the venture meter than for the orifice meter? What does this mean in terms of the total energy loss in the meters?1. Explain converging and diverging cone angles for the venture meter. Why is the diverging section so long (and the angle of this section so small)?1. How are eddy losses minimized in the diverging section of the venture meter?1. Can the equations given above be used for the measurement of flows of air? What changes would be required in the set-up?
15. Assessment Scheme:(a) process related (B) conclusion (C) Safety (d) Team work (e) would be done based on flowing measurable & Observable.
EXPERIMENT : 10COMPUTERIZED RECIPROCATING PUMP 1.Practical Significance To develop understanding of positive displacement pump, how they differ from centrifugal pump. 2. Competency Statement: Analyze performance characteristics of reciprocating pump. 3. skill: 1. Application of theoretical principle on real life situation. 2. Application of flow sensor. 3. Team work, critical thinking, problem solve.4. Experimental Object: To obtain the performance characteristics of a Computerized reciprocating pump.Theoretical Background:: A reciprocating pump is a device, driven by power from external sources, which when interposed in a pipe transfers mechanical energy to the liquid flowing through the pipe.The reciprocating pump is a positive displacement pump, I.e., it operates on the principle of actual displacement or pushing of liquid by a piston or a plunger that executes a reciprocating motion in a closely fitting cylinder. The liquid is alternatively Draw from the sump and filled in to suction side of the cylinder Led to the discharge side of the cylinder and emptied to the delivery pipe.The piston or plunger gets its reciprocating motion (moves backward and forward) by means of a crank and connecting rod mechanism.
Reciprocating pumpDemonstration:(i) The rotation of the crank causes the plunger to move backward and forward in the cylinder.(ii) Vacuum is created in the cylinder as the plunger moves to the right during suction stroke.(iii) The atmospheric pressure on the water surface forces the water up the suction pipe. The suction valve is opened and the water enters the cylinder. 01(iv) On the return stroke of the plunger (plunger moving to the left), called delivery stroke, the water pressure closes the suction valve and opens the delivery valve, forcing the water up the delivery pipe.(v) Again in the suction stroke the water is sucked from the pump and the cycle continues.
In a double acting reciprocating pump, suction and delivery strokes occurs simultaneously. A pump gives comparatively a more uniform discharge than the single acting pump, because of the continuity of suction and delivery strokes.6. Experimental Set-up:The present test rig is a self-contained unit operated on closed circuit basis. The pump, electric AC motor, collecting-measuring tank set, control panel are mounted on rigid frame work with anti-vibration mounts. The following are the provisions incorporated with the unit.For conducting the experiments at three or two speeds using AC Motor and a drive controller.1. The speed is indicated on digital RPM indicator. 2. To measure overall input power to the AC Motor using Wattmeter. 3. The delivery and suction head are measured by using pressure & vacuum sensors which are connected to a pressure scanner.4. For changing the Pressure (Delivery Head) and Vacuum (Suction Head) by operating the valves.5. The flow rate is calculated using measuring (collecting) tank and flow sensor which is connected within the delivery line.6. The overflow and butterfly valve are provided in collecting /measuring tank for recirculation of water for closed circuit operation.7. Change to different speed positions by using the drive controller and repeat the experiment either manually or by using computer interface software.7. Resource Required:S.r noName of ItemSpecification QuantityRemark
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8. Precaution:1. Dont start the pump if the voltage is less than 180V.2. Dont forget to give neutral and earth connections to the unit.3. Frequently (at least once in three months) grease/oil the rotating parts.4. At least once in a week, operate the unit & avoid clogging of moving parts.5. Replace the water possibly once in a month.6. Dont exceed 1.5 kg/cm2 on pressure gauge reading and never fully close the delivery valve.
9. Procedure:1. Fill the sump tank with clean water.2. Keep the delivery and suction valves open.3. Connect the power cable to 1 ph, 220V, 15 Amps.4. Meanwhile , switch -ON the Computer & keep it ready with the Observation Menu. 5. To go to Centrifugal pump test in computer follow the route, Start > Programs > Centrifugal Pump > Application.Comm Sett
6. Now on software screen click on the , Computer port setting dialog box will open, now select the required connected port and press OK.Start Test
7. After the computer port selection click on . A dialog box with the file name will be displayed, select the required file path and press OK. In the data indicator tab of the software all the values will start indicating as shown in the control panel.8. Set the speed of the pump either by adjusting the knob in the control panel or in the software.9. Keep the delivery valve fully open after priming.10. Once all the values are displayed on the software as per the values indicated in the digital indicators of the control panel click . and all the data will be logged in the data tabulation tab of the software along with performance graphs.Log DataLog Data
11. Log different values at different loadings by clicking . .. icon at different intervals. As the test is running, the computer will carry out all the Calculations and Tabulations with the Menu Display . Repeat the same procedure for other speed condition. Stop Test
12. To save the data click on the and all the logged data will be saved in the defined file path(Excel file format) selected at the time of starting the test.View file
13. To retrieve the recorded data click on and select the file used and press OK. All the logged data will be displayed in the software along with the graphs. Use the arrow keys to view the combustion graphs at different loads.14. After the experiment is over, keep the delivery valve open and switch-OFF the mains.10.Observation & Calculation: Discharge measurement (Q) = suction pressure, m = p1 Discharge pressure, m = p2 Flow rate, m3/sec = Q Total head across pump, H m = p2 - p1 Input power pi = P wattsWater power P0 = gHQ watts(Where is the mass density of the liquid being pumped)
Efficiency = X100 Vs = Swept volume of Piston in One minute VA = Actual Volume of water collected in one minute Where Va = Q x 60 cm3/minAt corresponding speed pickedVS = 2d2 l N Where d = dia of the piston = 5.5 cm l = stroke of piston = 4.0 cmN = Speed of pump in rpm % Slip = VS VA / VS
Sr.NoInput Power Speed(RPM)Suction Pressure P1 Delivery Pressure P2 Discharge QTotal Head (m) Output Power Efficiency (%) Slip (%)
1
2
3
4
11. Results:
12.Interpretation of ResultsGraph plot in Microsoft excel sheet.1. Discharge versus total head.2. Discharge versus efficiency. 3. Power output versus efficiency. 13. Conclusion:
14.Experiment related questions:1. What is difference b/w positive displacement machine and turbo machine ?2. What do you mean by surge tank ?3. What is principle behind pressurizing incompressible fluid by positive displacement machine ? 4. What is the velocity of fluid with respect to piston velocity? 5. What clearance factor ? what do you mean by clearance volume?15.Assissment Scheme:( a ) Process related (b) conclusion(c) Safety (d) Team work(e) would be done based on flowing measurable & Observable.
EXPERIMENT NO -11 GEAR AND VANE PUMP 1. Practical Significance:To develop understding of gear pump, especially regarding working and application. Also, to examine the performance of gear pump under different operating conditions. 2.Compytency statement: Students should be able to analyze the performance of pump. Understading of measurement devices for pressure, energy and rotational speed of the shaft. 3. Skill: 1. Application of energy meter. 2. learn to increase or decrease speed of a pump at same speed of motor by change of pulley. 3. Team work ,critical thinking, problem solve.4. Experimental Object: To obtain the efficiency of a gear pump under various head.5.Theortical Background: the gear pump which is of present concern falls into the category of Rotodynamic pumps. In this pump, the liquid is made to rotate in a closed chamber. This pump consist of two identical inter meshing spur pinions working in a fine clearance inside a casing. One of the pinions keyed to driving shaft. Alternatively one of the pinions can be integral with the driving shaft. The other pinion revolves idly. These pumps compared to reciprocating pumps are simple in construction, more suitable for handling viscous, turbid (muddy) liquids, can be directly coupled to high speed electric motors (without any speed reduction ) & easy to maintain. But, their hydraulic heads at low flow rates is limited, and hence not suitable for very high heads compared to reciprocating pump of same capacity. The present testing allows the students to understand and draw the operating characteristics at various heads, flow rates and spee 6. Experimental Set-up:The apparatus consists of a gear pump connected with a A.C. motor. The suction pipe is provided with a vacuum gauge for measurement of suction head. While at the discharge side a pressure gauge is fitted for measurement of the delivery head. A digital wattmeter may be connected to the motor of the pump as the motor is directly connected to the pump. A collecting tank is used to find the actual discharge through the pump.* Pump:Gear pump and Vane pump , 1HP.
7.Resourse Required:S.r. no Name Of ItemSpecification QuantityRemark
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8. Precaution:1. Dont start the pump if the voltage is less than 180V.2. Dont forget to give neutral and earth connections to the unit.3. Frequently (at least once in three months) grease/oil the rotating parts.4. At least once in a week, operate the unit & avoid clogging of moving parts.5. Dont exceed 4 kg/cm2 on pressure gauge reading and never fully close the delivery valve.6. In case of any major fault, it is suggested to contact the manufacturer before taking up any major repairs.9. Procedure: 1. Keep the delivery and suction valves open.2. Connect the power cable to 1 ph, 220V, 15 Amps.3. Select the Pump on which experiment to be conducted by changing selector switch position and set required speed using step cone pulley arrangement.4. Keep the delivery valve fully open after priming. 5. Switch-ON the Mains, MCB so that the Mains-ON indicator glows. Now switch-ON the motor.6. Note down the speed using digital RPM indicator using selector switch7. Note down the pressure Gauge, Vacuum Gauge and time for number of blinks of Energy meter .8. Operate the butterfly valve to note down the collecting tank reading against the known time, and keep it open when the readings are not taken.9. Repeat the experiment for different openings of the delivery valve (Pressure and Flow rate), note down the readings as indicated in the tabular column.10. Repeat the experiment for different speeds so that the pressure gauge reading are shown and repeat the steps (4 & 9).11. After the experiment is over, keep the delivery valve open and switch-OFF the mains.12. Calculate the results using formulae given and tabulate it.13. Draw the graphs of Head Vs Discharge.10. Observation & calculation:1. Discharge Rate ( Q ) IN m3/sec. Q = m3/sWhere, ( A ) = 0.127m2 is the area of collecting tank. ( R ) = the rise of level water collected in mm. ( T ) = time taken in second s for R mm rise of water 3. Total Head (H ) in mtr. H = p2 p1 P1 = Pressure at inlet section P2 = Pressure at outlet section Hydraulic Power ( Deliverd by the pump ) Output power ( PO ) = KW1 Electrical power as indicated by Energy meter: Input power ( Pi ) = KW n = Number of revolution of energy meter.t = is the time taken by the energy meter for n revolutions, in seconds.3200 is Energy Meter Constant. Efficiency Pump ( ) % = PO/Pi
s.r noDelivery Pressure "P" in Kg/cm2Suction Pressure "Pv" in mm of HgTotal Head "H" in mNo of blinkn Time Taken "t"SecDischarge Qa in m3/secPower output, Ppump in KWEfficiency
1
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11. Results:
12. Interpretation of result:Graph plot in Microsoft excel sheet.1. Discharge versus total head.2. Discharge versus efficiency.3. Power output versus efficiency.13. Conclusion:
14. Related short questions:1. Explain functioning of gear pump ?2. Why water can not be used in gear pump ? 3. Which type of gear is used in gear pump ? 4. How does the gear pump differs from vane type of pump ?15. Assessment Scheme:(a) Process related. (b) Conclusion.(c) Safety. (d) Team work.(e) would be done based on flowing measurable & Observable.
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Experiment No- 12 COMPUTERISED CENTRIFUGAL PUMP 1. Practical Significance: Selection of pump based on performance characteristics.2. Competency statement:Students should be able to plot the performance characteristics. Understand measuring devices for flow, pressure, energy and speed of shaft. 3. Skill:` 1. Application flow rate meter. 2. learn how to use RPM indicator. 3. Team work, critical thinking, problem solve.4. Experimental Objective:To obtain the head developed (H) vs. flow rate (Q) for a centrifugal pump, as well as associated parameters like efficiency, etc., at different RPMs. Note that the engineering Bernoulli equation from point 1 to point 2 is given by:
If applied between the outlet (2) and inlet (1) ports of a centrifugal pump, this gives:
5. Theoretical Background:The experimental rig is shown below. This test-rig is linked to a computer and has several digital indicators which may be read off directly. You must familiarize yourself with this unit before starting experiments The present test rig (see diagram) is a self-contained unit with the water being recirculated. The pump, electric AC motor, collecting-measuring tank set (with area of cross section = 0.127 m2) and the control panel are mounted on a rigid frame with anti-vibration mounts. The following are incorporated in the unit
6.Experimental Set-up:8. Experiments can be conducted at two or three RPMs using the AC motor (driving the centrifugal pump) and the drive controller9. The speed/RPM may be read off from the digital RPM indicator 10. The wattmeter is used to read off the overall input power, HPshaft, to the AC Motor. This power is different than the power input, HPpump, to the flowing water (which is QgH). These may be used to compute the pump efficiency, % pump =
11. The speed/RPM may be read off from the digital RPM indicator 12. The delivery and suction heads are measured by using the pressure/vacuum sensors which are connected to a pressure scanner. Valves may be used to change the pressure (delivery) and vacuum (suction) heads [Note: pressure head at a point = p/g]13. The flow rate is measured using the collecting tank and the flow sensor connected on the delivery line14. The manual drive controller (or the computer interface software) is used to change the RPM of the pump (and so the flow rate, etc.)15. * Pump:Centrifugal pump (Kirloskar make), 1.5 HP.
7. Resource required:S.r noName of ItemSpecificationQuantityRemark
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8. Precaution:1. Dont start the pump if the voltage is less than 180V.2. Dont forget to give neutral and earth connections to the unit.3. Frequently (at least once in three months) grease/oil the rotating parts.4. At least once in a week, operate the unit & avoid clogging of moving parts.5. Replace the water possibly once in a month. 6. Dont exceed 1.5 kg/cm2 on pressure gauge reading and never fully close the delivery valve.7. In case of any major fault, it is suggested to contact the manufacturer before taking up any major repairs.9. Procedure:1. Fill the sump tank with clean water.2. Keep the delivery and suction valves open.3. Connect the power cable to 1 ph, 220V, 15 Amps.4. Meanwhile , switch -ON the Computer & keep it ready with the Observation Menu. 5. To go to Centrifugal pump test in computer follow the route, Start > Programs > Centrifugal Pump > Application.6. Now on software screen click on the Comm Sett , Computer port setting dialog box will open, now select the required connected port and press OK.
7. After the computer port selection click on . A dialog box with the file name will be displayed, select the required file path and press OK. In the data indicator tab of the software all the values will start indicating as shown in the control panel.Start Test
8. Set the speed of the pump either by adjusting the knob in the control panel or in the software.9. Keep the delivery valve fully open after priming.10. Once all the values are displayed on the software as per the values indicated in the digital indicators of the control panel click . and all the data will be logged in the data tabulation tab of the software along with performance graphs.Log DataLog Data
11. Log different values at different loadings by clicking . aaaaa.. icon at different intervals.12. As the test is running, the computer will carry out all the Calculations and Tabulations with the Menu Display . Repeat the same procedure for other speed condition. Stop Test
13. To save the data click on the and all the logged data will be saved in the defined file path(Excel file format) selected at the time of starting the test.View file
14. To retrieve the recorded data click on and select the file used and press OK. All the logged data will be displayed in the software along with the graphs. Use the arrow keys to view the combustion graphs at different loads.15. After the experiment is over, keep the delivery valve open and switch-OFF the mains.10. Observation & calculation:1. Discharge Rate ( Q ) IN m3/sec. Q = m3/sWhere, ( A ) = 0.127m2 is the area of collecting tank. ( R ) = the rise of level water collected in mm. ( T ) = time taken in second s for R mm rise of water
3. Total Head (H ) in mtr. H = p2 p1 P1 = Pressure at inlet section P2 = Pressure at outlet section Sr.No.Input Power (W) Speed (RPM)Suction Pressure Delivery Pressure Discharge (Cu.m/s)Total Head (m) Output Power (W) Efficiency (%)
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Hydraulic Power ( Deliverd by the pump ) Output power ( PO ) = wHQ Input power ( Pi ) = From AC watt meter Efficiency Pump ( ) % = PO/Pi11.Results:
12.Interpritation of result:Graph plot in Microsoft excel sheet.1. Discharge versus total head.2. Discharge versus efficiency.3. Power output versus efficiency.13. Conclusion:
14. Related short question.1. What is cavitation?2. What is priming ?3. How to increase discharge by using more than one centrifugal pump?15. Assessment Scheme:(a) process related (b) Conclusion(c) Safety (c) Team work (e) would be done based on flowing measurable & Observable.
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