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
D. It has high power for take off
1 : 1.2
1 : 2
1 : 5
1 : 10
Compressor efficiency
Isothermal efficiency
Volumetric efficiency
Mechanical efficiency
0.2
0.3
0.4
0.5
Isothermally
Adiabatically
Isentropically
Isochronically
Pressure ratio
Maximum cycle temperature
Minimum cycle temperature
All of the above
Carbonisation of coal
Passing steam over incandescent coke
Passing air and a large amount of steam over waste coal at about 65°C
Partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast
Gas turbine
4-stroke petrol engine
4-stroke diesel engine
Multi cylinder engine
The combustion chamber in a rocket engine is directly analogous to the reservoir of a supersonic wind tunnel
The stagnation conditions exist at the combustion chamber
The exit velocities of exhaust gases are much higher than those in jet engine
All of the above
Pressure ratio
Maximum cycle temperature
Minimum cycle temperature
All of the above
Increase temperature
Reduce turbine size
Increase power output
Increase speed
It requires very big cylinder
It does not increase pressure much
It is impossible in practice
Compressor has to run at very slow speed to achieve it
The ratio of the discharge pressure to the inlet pressure of air is called compressor efficiency
The compression ratio for the compressor is always greater than unity
The compressor capacity is the ratio of workdone per cycle to the stroke volume
During isothermal compression of air, the workdone in a compressor is maximum
D₁/D₂ = p₁ p₂
D₁/D₂ = p₁/p₂
D₁/D₂ = p₂/p₁
None of these
Isothermal compression
Adiabatic compression
Isentropic compression
Polytropic compression
To supply base load requirements
To supply peak load requirements
To enable start thermal power plant
In emergency
Increases the thermal efficiency
Increases the compressor work
Increases the turbine work
Decreases the thermal efficiency
In gas turbine plants
For operating pneumatic drills
In starting and supercharging of I.C. engines
All of the above
Less power requirement
Better mechanical balance
Less loss of air due to leakage past the cylinder
Lower volumetric efficiency
Does not change
Increases
Decreases
First decrease and then increase
Low speeds
High speeds
Low altitudes
High altitudes
Gauge discharge pressure to the gauge intake pressure
Absolute discharge pressure to the absolute intake pressure
Pressures at discharge and suction corresponding to same temperature
Stroke volume and clearance volume
Lower at low speed
Higher at high altitudes
Same at all altitudes
Higher at high speed
No flow of air
Fixed mass flow rate regardless of pressure ratio
Reducing mass flow rate with increase in pressure ratio
Increased inclination of chord with air steam
Isothermal
Adiabatic
Polytropic
None of the above
200°C
500°C
700°C
1000°C
Increases thermal efficiency
Allows high compression ratio
Decreases heat loss is exhaust
Allows operation at very high altitudes
Turbojet engine
Ramjet engine
Propellers
Rockets
Start-stop motor
Constant speed unloader
Relief valve
Variable speed
Increases with increase in compression ratio
Decreases with increase in compression ratio
In not dependent upon compression ratio
May increase/decrease depending on compressor capacity
Turbojet
Turbo-propeller
Rocket
Ramjet