Don’t Leave it to Beaver A Hydroelectric Dam Engineering Teaching Kit The University of Virginia School of Engineering and Applied Sciences ©VMSEEI
Don’t Leave it to Beaver
A Hydroelectric Dam Engineering Teaching Kit
The University of VirginiaSchool of Engineering and Applied Sciences
Michael UnderhillMichael San Antonio
Colin O’BrienJason Kaplan
Point of Contact: Michael San [email protected]
Concepts:
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Hydrostatic Pressure, Potential and Kinetic Energy,Simple Machines, Electricity
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TABLE OF CONTENTS
Executive Summary_______________________________________________________2
Applicable SOL’s_________________________________________________________3
Materials Needed_________________________________________________________4
Unit Overview____________________________________________________________5
Unit Preparation_________________________________________________________7
Day 1: Intro to Hydroelectric Dams and Energy________________________________8Lesson Plan _________________________________________________________________8
Worksheet: Hydrostatic Pressure & Water Flow__________________________________12
Worksheet: Energy __________________________________________________________13
Day 2: Turbines and Mechanical Energy_____________________________________14Lesson Plan ________________________________________________________________14
Worksheet: Torque__________________________________________________________16
Day 3: Electricity and Magnetism___________________________________________17Lesson Plan ________________________________________________________________17
Worksheet: Electricity and Magnetism Exercise__________________________________20
Worksheet: Motors and Generators ____________________________________________21
Day 4: Integration and Testing_____________________________________________22Lesson Plan ________________________________________________________________22
Worksheet: Initial Hydroelectric System Design__________________________________24
Worksheet: Expectations _____________________________________________________25
Day 5: Competition ______________________________________________________26Lesson Plan ________________________________________________________________26
Worksheet: Lessons Learned__________________________________________________28
Citations ______________________________________________________________29
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Executive Summary
The mission of the Don’t Leave it to Beaver Engineering Teaching Kit is to educate middle school students on some major concepts in engineering and science in the inner workings of hydroelectric dams. While we are primarily concerned with the technical and engineering aspects of these systems, the broader context of “clean” energy is also an idea that this teaching kit drives home. Some of the main concepts included in this kit are potential, kinetic, and electrical energy and the relationships between them. Torque, motors/generators, and water flow are also key components of our lesson plan.
Considering the present energy crisis and issues of global warming facing the world, renewable and clean energy is an extremely important topic. Hydroelectric power is just one of a number of renewable solutions which include solar, wind, and geothermal power as well.
Throughout our process, students will see many demos, build various parts of the hydroelectric system, and make crucial decisions for their final product. They will learn to work as a team and fully experience the engineering design process. This process includes: problem identification, brainstorming, design, construction, testing, and improvement. Studies have shown that hands-on learning is extremely effective for engineering education. Younger students are more impressionable and develop constructs that will affect how they will learn in the future. Therefore, it is crucial to instill an early interest in engineering through fun and interactive activities. Our goal is to form the fundamental building blocks they need to solve critical problems of the future.
The entire lesson plan is centered around the competition on the fifth day. The concepts taught on the first few days are integrated into their final design. The students will select a generator, build a turbine and shaft structure, and route water incorporating those elements into a pre-built structure to create a complete hydroelectric dam within a tank. The teams will compete to produce the most electrical power. While the final results are important, we want the students to be able to explain their decision process and walk away from this experience with a greater interest in engineering.
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Applicable SOL’s
PS.1 The student will plan and conduct investigations in whicha) chemicals and equipment are used safelyb) length, mass, volume, density, temperature, weight, and force are accurately measured and reported using metric units (SI)c) conversions are made among metric units, applying appropriate prefixese) numbers are expressed in scientific notation where appropriateg) independent and dependent variables, constants, controls, and repeated trials are identifiedk) valid conclusions are made after analyzing datai) research methods are used to investigate practical problems and questionsn) an understanding of the nature of science is developed and reinforced
PS.6 The student will investigate and understand states and forms of energy and how energy is transferred and transformed. Key concepts includea) potential and kinetic energyb) mechanical, chemical, and electrical energy
PS.10 The student will investigate and understand scientific principles and technological applications of work, force, and motion. Key concepts includea) speed, velocity, and accelerationb) Newton’s laws of motionc) work, force, mechanical advantage, efficiency, and powerd) applications (simple machines, compound machines, powered vehicles, rockets, and restraining devices).
PS.11 The student will investigate and understand basic principles of electricity and magnetism. Key concepts include:a) static electricity, current electricity, and circuitsb) magnetic fields and electromagnetsc) motors and generators
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Materials Needed
Material Quantity Location Price/qty Manufacturer Part #2 liter soda bottle (2) 2 Common
Pitcher for pouring water 1 Common Tank 1 Whatever is available Ball 1 Common
String 1 Common
Corks2
types/group Plastic Spoon heads (various sizes) 1 set/group
Plastic Knives (various sizes) 1 set/group Popsicle sticks 1 box Balsa Wood
Glue (waterproof) 1/group Common Scissors 1/group
Permanent bar magnets 1 Set of 12 www.lakeshorelearning.com $7.80 Coiled wire 5 coils Allied Electronics Website $30.88/100 ft Alpha Wire 3051-BK005
Multi-Meter Test Leads 2 Allied Electronics Website $4.56/cable MuellerBU-1031-A-
24-2 Multi-meters 1/group Allied Electronics Website $29.24 each Amprobe DM7C
DC Brush motors (3 different choices) 3 per team Allied Electronics Website $16.77/motorParvalux Motors 52310
Batteries (various types) Wood (2x4, for dam support structure) Garden hose (or other access to water)
Plywood (Dam Construction) 1 sheet Available at hardware stores $20
Rubber Stoppers (3 different sizes)3 of each
size Available at hardware stores $1.00 Legos (shafts) Exacto Knives 1 set of 13 Available on amazon.com $6
Wood Glue Hot Melt Glue
Hose of various sizes Duct Tape
<Pictures of the non-common items will be added in the future>.
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Unit Overview
The first three days of this lesson plan are devoted to teaching a number of valuable concepts related to hydroelectric power generation. Activities and demos are used throughout these days to further enhance the ideas and allow students to learn more effectively. The fourth day is primarily a construction and integration class where students will have the opportunity to apply their new knowledge and work together in a team environment. The fifth and final day is reserved for the team competition of their hydroelectric systems and a general wrap up of the major ideas and lessons learned.
Day 1: Introduction to Hydroelectric Dams and Energy
Preliminary Lesson Summary:Students will be introduced to hydroelectric dams by showing them some famous
dams and explaining why they are important. Next, hydrostatic pressure and the various forms of energy will be discussed using demos and worksheets. The day will conclude with a demo of the example dam and a quick discussion of safety.
Objectives: Introduce students to hydroelectric dams and why they are important Educate students on the principle of hydrostatic pressure and how it relates to dam
structures, geometries, and power generation Educate students on three major forms of energy: potential, kinetic, electrical Address safety issues, especially with regards to water and electricity
Day 2: Turbines and Mechanical Energy
Preliminary Lesson Summary:Teams will be introduced to general examples of turbines and their basic
principles will be covered. Demonstrations will be used to explain the concept of torque and the methods to maximize it. As students gain an understanding of mechanical energy in turbines they will be introduced to their given materials and individually draw up possible designs for a turbine, giving them a chance to apply these principles. After some discussion team members will compare designs and then collaborate to build one turbine for their team, which will later be used during their final competition.
Objectives: Introduce students to turbines and how they are used in hydroelectric power
generation Describe principles of torque and maximization Encourage planning, design, and problem solving in the building process Student teams build their turbines for use in their hydroelectric systems
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Day 3: Electricity and Magnetism
Preliminary Lesson Summary:Teams will be introduced to the concepts of electricity and magnetism and how
they are used to produce power. Teams will learn how to perform some basic measurements on a vital electronic instrument called a multi-meter. They will then use the multi-meter to explore the functions of generators and motors and how they are different. They will conclude the lesson by analyzing a set of generators and will choose the best one to incorporate into their turbine design from Day 2.
Objectives: Explore fundamental concepts of electricity and magnetism Understand how motors and generators work and know how they are different. Understand basic circuit concepts Learn the basics of how to produce electrical power from mechanical work
Day 4: Integration and Testing
Preliminary Lesson Summary:Today consists mostly of allowing the students to work together freely in their
teams to complete their hydroelectric systems. Teams must integrate their parts made/selected from the first three days of this project and determine how best to direct the flow of water to their turbine. Additionally, as teams are ready, they may test their systems within the tank using water and make adjustments as necessary.
Objectives: Students integrate turbines and generators from days 2-3 Groups determine how best to funnel the water from the dam Teams complete their hydroelectric systems Students test systems and make adjustments as necessary
Day 5: Competition
Preliminary Lesson Summary:Today is the day of the grand competition where students’ hopes and dreams will
be either fulfilled or crushed in a climax of excitement, but either way they will be learning! Each of the teams will have an opportunity to test their systems and attempt to generate the most power. Afterwards, the lessons learned will be summarized and stressed for better retention.
Objectives: Every team has the opportunity to test their hydroelectric system Students learn the concepts covered in days 1-4 by seeing them in action All major concepts are reviewed afterwards Students provide feedback on their team, the competition, and lessons learned
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Unit Preparation
<After we have determined the best method for constructing the dam, we will write up directions here for the teachers to construct their own dams within the tank.><We will contain construction pictures within our explanations.>
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Day 1: Intro to Hydroelectric Dams and Energy
Extended Lesson Summary:Students will be introduced to the basics of hydroelectric dams, how they derive
their energy, and why they are shaped the way they are. The advantages and drawbacks of hydroelectric dams will be discussed to give students an idea of the bigger picture of power generation. A few famous dams will be displayed and discussed to stimulate interest and further emphasize the importance of hydroelectric power. Hydrostatic pressure is a major concept that will assist in describing the structure and design of dams and this concept will be explored in the lesson plan. Next, the various forms of energy (potential, kinetic, electrical) will be discussed while using worksheets and demos to increase the understanding of these important physical properties. Students will be introduced to their competition while seeing a completed hydroelectric dam in action. Finally, they will be broken up into teams. It is vital to discuss a few safety precautions on this day as well, notably the safety issue of working with water and electricity in close proximity.
Objectives: Introduce students to hydroelectric dams and why they are important Educate students on the principle of hydrostatic pressure and how it relates to dam
structures, geometries, and power generation Educate students on three major forms of energy: PE, KE, EE Get students excited about the rest of the week and the design competition Address safety issues, especially with regards to water and electricity
Virginia SOL’s: PS. 1a PS. 6a, PS. 6b
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Materials:2 liter soda bottle (2)Scissors or KnifePitcher for pouring waterTank (to catch the water)BallStringWorksheets: Hydrostatic Pressure & Water Flow, Energy
Teacher Prep ( 20 min ): Make photocopies of two worksheets (One copy per student)Prepare PowerPoint or overhead slidesCut holes in soda bottles – three different heights in one, three different sizes in the otherAttach ball to string securelySecure other end of string to fixed object
Detailed In Class Lesson Plan:
Introduction to Hydroelectric Dams (10 min):Students will be presented a short power point (overhead transparencies if
necessary) of some famous dams. A few very basic images will be shown to students to help reveal the major elements and operations of a hydroelectric dam. Finally discussion of the advantages and drawbacks of hydroelectric dams will give students a clear understanding of the broad issues faced in power generation.
General Concepts for StudentsWater has energy from the air above pushing down on itWater gets pushed into the tunnel where it gains speedWater falls onto turbine causing it to spinSpinning turbine producers power in the generatorGenerator converts spinning energy into electricity
Discussion of Hydrostatic Pressure and Water Flow (15 min):Teacher will break down the word
Hydro – having to do with waterStatic – staying stillHydrostatic – still water
Demo: Teacher will then demonstrate hydrostatic pressure with a 2 liter soda bottle and three holes at various heights. The water at the bottom hole shoots out faster than from the holes above it. In order to illustrate water flow principles, another bottle should have three holes of different sizes all at the same height. Now, the water from the smallest hole shoots out faster than from the other holes. Students will try to figure out why and fill out the Hydrostatic Pressure & Water Flow worksheet. Teacher will aid students with this worksheet.<Once we have tested this demo, we will include a picture here with the explanation.>Finally, the teacher will show them the hydrostatic pressure and mass flow equations.
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pressure = density*gravity*heightmass flow = area*density*velocity
Teacher explains how the phenomena affect the structure and design of a dam.
Discussion of Energy (15 min):Teacher will explain how both Potential and Kinetic energy are associated with
hydroelectric power and touch upon electrical energy (to be taught in great detail on day 3).
Potential Energy – exists when there is a force that tends to pull an object back to its original position, after it was displaced
Examples: Gravity pulls object to the ground, and Springs pull themselves together
Gravitational potential energy is important in hydroelectric damPE = mass*gravity*height
Kinetic Energy – exists when there is an object in motion that contains mass.Examples: cars, baseball, (students give some examples)Water moving through tunnel is the kinetic energy in a hydroelectric dam
KE = ½ *mass*velocity2
Pendulum Demo: Teacher holds up a ball on a string and lets it go to see it swing back and forth. Potential energy is greatest at its peak and kinetic energy is greatest at its lowest point.<Once we have tested this demo, we will include a picture here with the explanation.>
Electrical Energy – exists when there is a flow of electrons through a load.Electrical energy is the output of a hydroelectric dam and is the energy that
powers the TVs and light bulbs in one’s home.
Here are some links to further information on these concepts if you need a refresher:Forms of Energy: http://www.eia.doe.gov/kids/energyfacts/science/formsofenergy.htmlPendulum Demo: http://www.bsharp.org/physics/stuff/swings.htmlHydrostatic Pressure: http://en.wikipedia.org/wiki/Fluid_statics#Hydrostatic_pressure
Demonstration of Instructor’s Dam (5 min):The teacher will show students their version of a hydroelectric dam in order to
prove to the students that moving water really can produce electricity. Avoid showing students the inner workings of the dam by covering the major components to promote innovative ideas for their competition. The design competition is introduced at this point in the lesson and the class will break up into teams.<Once we have done this ourselves we will include a picture here.>
Wrap Up (5 min):
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Students will be informed of safety measures when dealing with water and electricity. Also safety in using the tools such as knives or rough sandpaper shall be addressed. Teacher will first ask class what they learned during this lesson. Then the teacher will inform students of up coming lesson plans and concepts.
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Name __________________________________ Date _______________ Class _______
Hydrostatic Pressure & Water Flow
Definitions:Hydro - having to do with waterStatic - Something that is not in motion
Hydrostatic - water at rest
Questions:Hydrostatic Pressure DemoFor bottle number 1, out of which hole do you think the water will shoot the fastest? (Circle One)
Bottom Middle Top All the same
Explain why some of the holes made the water shoot faster than others?
For bottle number 2, out of which hole do you think the water will shoot the fastest? (Circle One)
Small Medium Large All the same
Explain why some of the holes made the water shoot faster than others?
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Name __________________________________ Date _______________ Class _______
Energy
Brainstorm: Name all of the forms of energy that you can think of:
Questions:Pendulum Demo1) What or who gave the ball its initial energy?
2) How fast is the ball traveling when it reaches the top of its cycle?
3) At what point is the ball traveling the fastest?
4) At what point in the path of the ball is the potential energy the greatest?
5) At what point is the kinetic energy the greatest?
Brainstorm: Name several things in your house that use electrical energy.
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Day 2: Turbines and Mechanical Energy
Extended Lesson Summary:Day 2 will continue the discussion on energy by converting potential and kinetic
energy into mechanical energy. Students will learn the fundamental mechanics of torque through applications of turbines. Worksheets and demonstrations will be used to further explain more advanced topics. After the lesson, students will begin to design their own turbines with a given set of materials. After discussing key features in their designs, the students will go back to their teams and build their own turbine to be used in their hydroelectric system.
Objectives: Introduce students to turbines. Educate students on principles of torque and how it is maximized Discuss energy conservation and transfer within turbines Allow students to design and build their own turbines.
Virginia SOL’s: PS. 1 PS. 6 PS. 10
Materials:CorkPlastic Spoon heads (various sizes)Plastic Knives (various sizes)Popsicle sticksBalsa WoodGlueScissorsWorksheets: Torque
Teacher Prep ( 15 min ): Make photocopies of torque worksheets (one copy per student)Prepare PowerPoint or overhead slidesSet up materials for student construction
Detailed In Class Lesson Plan:
Introduction to Turbines (10 min):Students will be presented a short power point (projector slides if necessary) of
examples of turbines. Possible general examples are water wheels, windmills, power plants and full scale hydroelectric dams. It is important to not give away too many hints that would limit their creative thinking.
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Turbines:Force of water causes rotational motion of turbine.Begin to question students on concept of torque.
Discussion of Torque (10 min):Discuss what causes object to rotate. Go through worksheet questions. Introduce
concept of torque. Have students attempt opening door from different points as in the Torque worksheet. Ask students to explain through torque definition, why door is easier to open from outside (ie. at the knob).
τ = Force x Moment ArmDemonstration with See-Saw. Balance weights on opposite side of fulcrum. Show that a smaller weight further from center, can balance with larger weight closer in. Reinforce torque concepts in discussion for building their turbines.
Here’s a link with a refresher on torque:http://en.wikipedia.org/wiki/Torque
Introduce Student Design and Individual Drawing (5 min):Show students the materials they will be given. Ask them to draw out basic
designs. Allow a few minutes for drawing. <Once we have done this ourselves we will include example pictures of basic designs of turbines for the teacher’s reference.>
Building (20 min):After a discussion on safety (knives, scissors, crazy glue), allow students to join
into their groups. Promote discussion amongst groups in deciding on plans. Distribute materials to each group and then ask them to draw their group plan for a turbine. Allow time for students to build while providing advice. Encourage groups to run water over their turbine during building process and then improve their design if necessary.
Wrap Up (5 min):Teacher will first ask class what they learned during this lesson. Then the teacher
will inform students of upcoming lesson plans and concepts.
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Name __________________________________ Date _______________ Class _______
Torque
Which direction will the see-saw fall? (Circle one and explain)
Left Right Neither
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Door Example:
Which position will the door be easiest to open at? (Circle one and explain)
A B C
Doesn’t Matter
Day 3: Electricity and Magnetism
Extended Lesson Summary:Teacher will introduce students to the basics of electricity and magnetism and
how they are two key phenomena used to produce electrical power from mechanical work. Today’s lesson will begin with teaching the class a little about circuits and how electrons flow to produce electric current. The class will then divide into teams and will learn how to operate a multi-meter. They will explore that when there is electricity flowing through wire, magnetic fields are produced and vice versa. If there is time, the students will get to see the inner workings of a generator and be able to explain how they work. The conclusion of the lesson will be for the teams to analyze a set of 3 generators to determine which one will produce the most power for their hydroelectric system.
Objectives: Explore fundamental concepts of electricity and magnetism Understand how motors and generators work and know how they are different. Understand basic circuit concepts Learn how to produce electrical power from mechanical work
Virginia SOL’s: PS. 1 PS. 6b PS.11
Materials:Permanent magnetsElectrical cables (For connecting multi-meters and generators)Coiled wireAlligator clipsBanana plugsMulti-metersDC Brush motors (3 per team)Batteries (various types)Worksheets: Electricity and Magnetism, Motors and Generators
Teacher Prep ( 20 min ): Make photocopies of two worksheets (one copy per student)Assemble materials for each activity and distribute for each group.
Detailed In Class Lesson Plan:
Introduction to Electricity and Magnetism (5 min):Students will be presented a short power point (projector slides if necessary) of
electric circuits. They will be able to understand that closed loops are necessary for current to flow and that voltage is the driving factor that produces current. They will also
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be shown some slides dealing with magnetism and some basic concepts such as poles and magnetic fields influencing the attraction and repulsion of objects. Finally, for safety measures the teacher will explain why it’s important that they not directly attach the positive end of the battery to the negative end (it will get very hot!). Also, the teacher should stress that students not touch the two probes of the multi-meter together (may break depending on what it’s measuring!).
Here are some links with refreshers on electricity and magnetism concepts:http://science.howstuffworks.com/electricity.htm http://science.howstuffworks.com/electromagnet.htm
First activity (20 min):Teacher will show teams how to use a multi-meter and give them a worksheet to
fill out to evaluate what they know about it. The teacher will have them measure the voltage drop across a standard battery. If there’s time, the teacher may want to ask them to measure the current on their own. It would be a trick question because the current flow would be infinite because there would be no resistance in the circuit. This will get them to think about the concept of resistance in closed-loop circuits.<We will include a picture of the multi-meter here>
Here is a link to a site with directions on how to use the digital multi-meter:http://www.ehow.com/how_4499779_read-digital-multimeter.html
To illustrate the concept that allows generators to convert mechanical work into electricity, have the teams take their magnet and move it back and forth through the coiled wire. The teacher will have them measure the voltage produced by these motions and let them figure out what motions and factors produce the most voltage.< We will include a picture demonstrating this activity here>
If there is time, show teams the inside of a broken motor/generator. Show them where the magnets and coil are and explain how what goes on inside the generator is directly related to the experiment in the preceding paragraph. <We will include a labeled picture of the inside of one of our generators>
Second Activity (20 min):Teacher will explain the differences between generators and motors. Motors
transform electrical energy into mechanical work while generators do the opposite. The teacher will then pass out a set of 3 generators for each team. Each generator in the set should have a different gearing ratio making some more difficult to turn than others. Each team will complete the worksheet corresponding to the activity with three generators. The teacher should inform the teams that it will be more difficult to turn the shaft of the generator at the same speed while measuring the current. Also, the teacher should show the teams that Power = Voltage x Current to fill in the last column. In the end, each team will pick the generator from their set to use on Day 4 when they put together the entire hydroelectric system.<We will later include a picture of people working with the generators>
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Wrap Up (5 min):Teacher will first ask class what they learned during this lesson. Then the teacher
will inform students of plan for tomorrow.
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Name __________________________________ Date _______________ Class _______
Electricity and Magnetism Exercise
1. On the circuit diagrams on the left, indicate what direction the current is flowing. Draw the magnetic field lines for the magnet on the right.
Use the multi-meter to measure the voltage drop across the battery.
2. Voltage of the battery read from the multi-meter: ______________ V
3. Which of the following greatly influenced the voltage you obtained from moving the magnet around the coil?
A) Distance of magnet from coil
B) Speed of magnet
C) Orientation of magnet
D) Number of Coils
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Bulb
N
S
Name __________________________________ Date _______________ Class _______
Motors and Generators
1. Draw an arrow in between the electrical and mechanical blocks showing the direction of energy transfer for a generator and a motor.
2. Fill in the table while following the steps below. At the end of this exercise, decide which of the three generators will work the best for your team’s turbine.
Determine the following for all 3 Generators using the multi-meter:
Hook up multi-meter to the wires coming out of the generator. (Remember: Red is Positive, and Black is Negative or Ground)
Turn the shaft of the generator until you can get it to spin at a comfortable speed and maintain it. (Note: Turn at this same speed for all generators)
Generator # Difficulty to Move
Voltage (V) Current (A) Power (W)
1
2
3
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Motor Generator
Electrical Mechanical Electrical Mechanical
Day 4: Integration and Testing
Extended Lesson Summary:At the beginning of class there will be a very short recap of what the students
have learned in the first three days and how it all fits together. The rest of the class consists of allowing the students to work together freely in their teams to complete their hydroelectric systems. Teams must integrate their parts made/selected from the first three days of this project and determine how best to direct the flow of water to their turbine. Additionally, as teams are ready they may test their systems within the tank using water and make adjustments as they deem necessary.
Objectives: Students integrate parts from days 1-3 Groups determine how best to funnel the water from the dam Teams complete their hydroelectric systems Students test systems and make adjustments as necessary
Virginia SOL’s:PS.1 a,k,i,nPS.6 a,bPS.10 a,c,d
Materials:Tank with pre-constructed structureAccess to waterSeveral boards with holes cut outRubber StoppersLegosBalsa WoodExacto KnivesWood GlueHot Melt GlueStrawsHoses of various sizesMaterials from days 1-3Worksheets: Initial Hydroelectric System Design, Expectations (One per student)
Teacher Prep (20 min)Assuming the boards are already madeMake photocopies of two worksheetsLay out all materialsPrepare tank and water source for testing
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Detailed In Class Lesson Plan:
Introduction (5 min)Present a brief recap of what students have made and done over the last three
days. Explain to the students that today is when everything comes together. Review the basics of how a hydroelectric dam works using the picture below.
Team Construction and Testing (40min)Break class back up into teams and have them work on completing their
hydroelectric system. This involves connecting the turbine and motor through a shaft system and also includes deciding on where to release water and use tubes, ducts, etc to route water from dam to turbine. Actively walk around and aid students with construction. Try not to answer too many of the students’ questions; remember there is no right or wrong way to do this project. As students complete their systems, allow them to test in the tank and make observations and adjustments as they wish. Also they are to fill out the first worksheet by the end of class.
Wrap-up (5min)Briefly cover the plan for the competition on Day 5. Be sure to have the students
come ready to go for the completion and, if desired, provide information on additional times that they may work on their hydroelectric systems (ie. Lunch time). Assign Expectations worksheet as homework.
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Name __________________________________ Date _______________ Class _______
Initial Hydroelectric System Design
In the space provided, make a rough sketch of your team’s hydroelectric system. Label the Turbine, Generator, and the path the water should take.
Explain why you chose your design. Some questions you might discuss: Why did you orient the turbine as you did? Why did you choose that hole on the dam for the water flow? Why did you link the turbine shaft and generator as you did?
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Name __________________________________ Date _______________ Class _______
Expectations
What are your expectations for how your hydroelectric system will perform? Explain your reasons.
What would you change if you had another day to work on your system?
If your team had an opportunity to test your dam, what observations did you make as to how your hydroelectric system performed? What adjustments (if any) did you make to your system after testing?
At this point, without knowing how your hydroelectric system performs, are you happy with your team’s design? If you could do it all over again what would you do differently? Why?
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Day 5: Competition
Extended Lesson Summary:Today is the day of the grand competition where students’ hopes and dreams will
be either fulfilled or crushed in a climax of excitement, but either way they will be learning! Each of the teams will have an opportunity to test their systems and attempt to generate the most power. Afterwards, the lessons learned will be summarized and stressed for better retention.
Objectives: Every team has the opportunity to test their hydroelectric system Students learn the concepts covered in days 1-4 by seeing them in action All major concepts are reviewed afterwards Students provide feedback on their team, the competition, and lessons learned
Virginia SOL’s:
Materials:Tank to hold dams, water, and hydroelectric systemPre-constructed support structure and testing damAccess to waterSeveral boards with holes cut outRubber StoppersDuct TapeMulti-meterAll construction materials from Days 1-3 for last minute repairsWorksheets: Lessons Learned (One per student)
Teacher Prep (20 min)Prepare the tank in an area with access to water and a drain, and in a location
easily viewable by the students. Be sure to have the tank situated properly before filling with water as it will likely be too heavy to move once this is done. Place the dam against the support structure inside the tank. Plug all holes of the dam and seal the dam against the bottom and sides of the tank. Fill the water side of the tank with water before class, allowing some time to fix any leaks that may occur. Open one hole and test to make sure that the drain works properly and that your hose to refill the water side is functional (may use a bucket instead). Finally, make copies of the Lessons Learned Worksheet for the class.<We will include pictures of the fully set up dam structure for the teacher to refer to>
Detailed In Class Lesson Plan:
Introduction (5 min)Quickly recap the plan of the day and decide on the first few groups to go. Tell
teams that they may make any changes and last minute updates as other teams are tested. Additionally, tell the teams that, if time permits, they may retest their hydroelectric
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systems if something goes wrong the first time, but only after all the teams have had a chance to go.
Competition (40 min)Conduct the competition by testing the teams’ systems one at a time. Place the
system to be tested within the tank against the support structure and dam with all holes currently closed so no water is flowing. Be sure to open the drain on the dry side of the dam and have the water exiting the tank to keep this side relatively dry. Teams will each have 3 minutes to set up their system. When ready, the team will remove the stopper that they wish to allow water to flow. Each test will be 2 minutes in length, and the team will get a score based on the maximum power generated during this time. Once the team is done, replace the stopper to close the water flow. The team will remove their system and another team will begin their setup.<We will include a picture of a working hydroelectric dam in action!!!>
Wrap-up (5min)Congratulate all teams on their performance. Announce the winner of the
competition! Pass out the Lessons Learned Worksheet either for homework or to fill out at the end of class as time permits. Make any closing remarks that you wish.
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Name __________________________________ Date _______________ Class _______
Lessons Learned
How did your hydroelectric system perform during the competition?
Now that you have seen how your team’s hydroelectric system operated, what changes would you make if you could do it again?
What did you learn from this project?
Did your team work well together? What could be improved in the future? Would you like to work with these people again on another project? Why or why not?
How could this project be improved in the future?
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Citations
Beaver on Cover Page:http://ci.marysville.wa.us/PublicWorks/swm/docs/beaver.htm
Dam on Cover Page:http://www.hydropowerusa.com/
Hoover Dam on Page 7:http://gocalifornia.about.com/bl_nvhdamphoto_dam.htm
Schematic of Hydroelectric Dam on Page 20:http://www.window.state.tx.us/specialrpt/energy/renewable/hydro.php
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