p₂ = p₁ × p₃
p₂ = p₁/p₃
p₂ = p₁ × p₂
p₂ = p₃/p₁
C. p₂ = p₁ × p₂
Work required to compress the air isothermally to the actual work required to compress the air for the same pressure ratio
Isothermal power to the shaft power or B.P. of the motor or engine required to drive the compressor
Volume of free air delivery per stroke to the swept volume of the piston
Isentropic power to the power required to drive the compressor
Surrounding air
Compressed atmospheric air
Its own oxygen
None of these
Lowest
Highest
Anything
Atmospheric
It allows maximum compression to be achieved
It greatly affects volumetric efficiency
It results in minimum work
It permits isothermal compression
A propeller system
Gas turbine engine equipped with a propulsive nozzle and diffuse
Chemical rocket engine
Ramjet engine
Equal to
Less than
More than
None of these
Heated
Compressed air before entering the combustion chamber is heated
Bled gas from turbine is heated and readmitted for complete expansion
Exhaust gases drive the compressor
Turbojet
Turbo-propeller
Rocket
Ramjet
These are used to dampen pulsations
These act as reservoir to take care of sudden demands
These increase compressor efficiency
These knock out some oil and moisture
It has high propulsive efficiency at high speeds
It can fly at supersonic speeds
It can fly at high elevations
It has high power for take off
34 %
50 %
60 %
72 %
Isothermal H.P/indicated H.R
Isothermal H.P./shaft H.R
Total output/air input
Compression work/motor input
Cools the delivered air
Results in saving of power in compressing a given volume to given pressure
Is the standard practice for big compressors
Enables compression in two stages
kg/m²
kg/m³
m³/min
m³/kg
Same
One-half
One fourth
One sixth
200°C
500°C
700°C
1000°C
Adiabatic temperature drop in the stage
Total temperature drop
Total temperature drop in the stage
Total adiabatic temperature drop
Increase in net output but decrease in thermal efficiency
Increase in thermal efficiency but decrease in net output
Increase in both thermal efficiency and net output
Decrease in both thermal efficiency and net output
Toughness
Fatigue
Creep
Corrosion resistance
6000 KW
15 KW
600 KW
150 KW
High calorific value
Ease of atomisation
Low freezing point
Both (A) and (C) above
10 bar
20 bar
30 bar
50 bar
1
1.2
1.3
1.4
High nickel alloy
Stainless steel
Carbon steel
High alloy steel
Centrifugal pump
Reciprocating pump
Turbine
Sliding vane compressor
Reciprocating compressor
Centrifugal compressor
Axial flow compressor
Turbo compressor
Indicated power
Brake power
Frictional power
None of these
0.5 kg
1.0 kg
1.3 kg
2.2 kg
Vi = Vo
Vt > Vo
U < Vo
V = Uo
Radial flow
Axial flow
Centrifugal
None of the above