10 Stall and Surge, Surge Control Methods Multi spool compressor, variable vanes, air bleed..pptx 10 Stall and Surge, Surge Control Methods Multi spool compressor, variable vanes, air bleed..pptx Your score increases as you pick a category, fill out a long description and add more tags.

1. 1
FLOW COMPRESSORS - SINGLE STAGE, MULTISTAGE
COMPRESSOR
Compressors: A flow compressor is a mechanical
device that increases the pressure of a gas by
reducing its volume through dynamic or positive
displacement means.
Applications: Aerospace propulsion, gas turbines,
HVAC systems, industrial processing.
Classification of Compressors:
• Based on Flow Direction:
 Axial Flow Compressor
 Centrifugal (Radial) Flow Compressor

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FLOW COMPRESSORS - SINGLE STAGE, MULTISTAGE
COMPRESSOR
• Based on Staging:
• Single Stage Compressor
• Multistage Compressor
Single Stage Axial Compressor
• A compressor with one rotor and one stator stage.
Working Principle:
 Rotor imparts kinetic energy to the fluid.
 Stator converts kinetic energy to pressure energy.

3. 3
FLOW COMPRESSORS - SINGLE STAGE, MULTISTAGE
COMPRESSOR
Equations – Single Stage Compressor:
Euler’s Turbomachinery Equation: Δ h0 = U⋅ΔVθ
• Δh0​
: Stagnation enthalpy rise (J/kg)
• U: Blade speed at rotor tip (m/s)
• ΔVθ ​
: Change in tangential velocity component (m/s)
Isentropic Efficiency (ηs ) = [h02−h01] / [h02s−h01]
• ηis​
: Isentropic efficiency
• h02​
, h01​
: Total enthalpy at outlet and inlet
• h02s​
: Total enthalpy for isentropic process

4. 4
FLOW COMPRESSORS - SINGLE STAGE, MULTISTAGE
COMPRESSOR
6.Multistage Compressors
Consists of multiple rotor-stator stages to achieve
higher pressure ratios.
Advantages:
• Higher total pressure rise
• Improved efficiency with interstage cooling
Use Cases: Jet engines, industrial gas compressors

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FLOW COMPRESSORS - SINGLE STAGE, MULTISTAGE
COMPRESSOR
Multistage Compressor Performance
1.Total Pressure Ratio =
• ​
P0: Stagnation pressure
• T0​
: Stagnation temperature
• γ : Ratio of specific heats
2. Overall Efficiency ηoverall =
(T0,exit−T0,inlet) / (Ts
0,exit​
−T0,inlet​
​)

6. 6
FLOW COMPRESSORS - SINGLE STAGE, MULTISTAGE
COMPRESSOR
8: Velocity Triangles: Illustrates relative and
absolute velocities at blade inlet / outlet. The
figure 2, Show the Inlet and outlet velocity
triangles
Where
• V: Absolute velocity,
• U: Blade speed,
• W: Relative velocity

7. 7
FLOW COMPRESSORS - SINGLE STAGE, MULTISTAGE
COMPRESSOR
Degree of Reaction (R) = Δh rotor / Δh stage
= 1/2(1−V2θ+V1θ) / U
• Indicates the distribution of static enthalpy rise
between rotor and stator.
• Ideal for R=0.5, represents equal pressure rise
in rotor and stator.
Design Parameters:
• Tip Mach Number (Mt),
• Flow Coefficient ( )
ϕ = Vax / U
• Work Coefficient (ψ) =Δh0 / U2

8. 8
FLOW COMPRESSORS - SINGLE STAGE, MULTISTAGE
COMPRESSOR
Losses in Compressors
• Profile losses
• Secondary flow losses
• Tip clearance losses
• Skin friction

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