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 Different Type of 

Compressors 

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Different Type of Compressors 

• Positive Displacement

Compressors

• 1- Reciprocating

• 2- Rotary 

• 2-1 Vane

• 2-2 lobe

• 2-3 Screw

• Dynamic Compressors 

• 1- Axial

• 2- Radial Centrifugal

compressor) 

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Types of Compressors

• Axial Compressors

• Fluid flow is parallel to axis of rotation

• Used in modern aircraft

• Have several stages to increase compressor 

 pressureratio

• Used in modern gas turbine engines

•   Centrifugal Compressor

• Fluid flow is perpendicular to the axis of rotation

• Used in first jet turbine engines

• Have a larger CPR per stage

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Axial Compressors 

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Axial Compressor 

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Axial Compressors

 • What is it?

A number of stages of alternate rotating andstationary airfoil-section blades, attached to discsor a drum, which force the incoming air through a

divergent angular duct.

• How does it work?

Air is accelerated as it passes through each stage by rotating blades and forced rearwards throughstationary blades which reduce velocity andincrease pressure.

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Advantages of Axial-Flow

Compressors

• High overall pressure ratio (p)• High h

• Small front area (high mass flux)

• Steady increase in p/stage

• High Mach numbers

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Disadvantages of Axial-Flow

Compressors

• Good efficiency over narrow rotational speed

range.• Difficulty of manufacture and high cost.

• Relatively high weight.

• High starting power requirements (this has been

 partially overcome by split compressors).

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Axial Compressor 

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Axial Compressor 

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Axial Compressor 

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Axial Compressor 

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Basic Design of Axial

Compressor 

• The axial compressor produces small

increases in pressure per stage

• Each stage consists of first a revolving rotor 

followed by a stationary stator 

• The rotor gives the energy to the fluid flow

• The stator increases pressure and keeps the

flow from spiraling around the axis.

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Basic Design of Axial

Compressor 

• Fluid enters compressor where the blades

are longer and exits where blades are

shorter, opposite of the turbine

• Must be designed in such a way as to

 prevent stall

• Use of velocity diagrams will determine blades angles

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Multistage axial compressors

• Multistage axial flow compressors will produce much larger CPR then single stage

compressors• Largest pressure ratio is in first stage

• To calculate the average pressure ratio

• needed per stage for a set pressure ratio• ASPR = PRtotal^ 1/n

• Where n is the number of stages needed

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Axial

Compressor 

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Axial Compressor Stage 

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Axial Compressor 

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Axial and Centrifugal Compressor 

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Blade Fixation

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Three stage Axial Compressor 

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Schematicdiagram of 

changes in fluid

properties and

velocity through

an axialcompressor

stage.

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Axial Compressor Section

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Axial Compressor Cutaway 

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Axial Compressor First Stage

Rotor

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Axial Compressor Rotor and

Casing 

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Axial Compressor Stage 

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Euler Equation

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A Note on Enthalpy

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Stage Pressure Ratio and Speeds

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Degree of Reaction

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Dimensionless Groups

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•Thank you for your

attention