Constant volume
Constant temperature
Constant pressure
None of these
C. Constant pressure
Compressor efficiency
Volumetric efficiency
Isothermal efficiency
Mechanical efficiency
Cool the air
Decrease the delivery temperature for ease in handling
Cause moisture and oil vapour to drop out
Reduce volume
1 - k + k (p₁/p₂)1/n
1 + k - k (p₂/p₁)1/n
1 - k + k (p₁/p₂) n- 1/n
1 + k - k (p₂/p₁) n-1/n
Highly heated atmospheric air
Solids
Liquid
Plasma
Pressure ratio alone
Maximum cycle temperature alone
Minimum cycle temperature alone
Both pressure ratio and maximum cycle temperature
Remain same
Decrease
Increase
None of the above
kg/m²
kg/m³
m³/min
m³/kg
In one cylinder
In two cylinders
In a single cylinder on both sides of the piston
In two cylinders on both sides of the piston
34 %
50 %
60 %
72 %
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, eke, anthracite coal or charcoal in a mixed air steam blast
Single stage compression
Multistage compression without intercooling
Multistage compression with intercooling
None of these
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
6 kg/cm²
10 kg/cm²
16 kg/cm²
25 kg/cm²
Less
More
Same
May be less or more depending on ambient conditions
Temperature during compression remains constant
No heat leaves or enters the compressor cylinder during compression
Temperature rise follows a linear relationship
Work done is maximum
Large discharge at high pressure
Low discharge at high pressure
Large discharge at low pressure
Low discharge at low pressure
Isothermal compression
Adiabatic compression
Isentropic compression
Polytropic compression
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
Atmospheric
Slightly more than atmospheric
Slightly less than atmospheric
Pressure slightly less than atmospheric and temperature slightly more than atmospheric
Pressure ratio
Pressure coefficient
Degree of reaction
Slip factor
Increase
Decrease
Remain same
May increase or decrease depending on clearance volume
Mechanical efficiency
Volumetric efficiency
Isothermal efficiency
Adiabatic efficiency
It allows maximum compression to be achieved
It greatly affects volumetric efficiency
It results in minimum work
It permits isothermal compression
H.P. compressor is connected to H.P. turbine and L.P. compressor to L.P. turbine
H.P. compressor is connected to L.P. turbine and L.P. compressor is connected to H.P. turbine
Both the arrangements can be employed
All are connected in series
Net work output and heat supplied
Net work output and work done by turbine
Actual heat drop and isentropic heat drop
Net work output and isentropic heat drop
Isothermal
Adiabatic
Polytropic
None of the above
1 : 1
2 : 1
4 : 1
1 : 6
Large gas turbines employ axial flow compressors
Axial flow compressors are more stable than centrifugal type compressors but not as efficient
Axial flow compressors have high capacity and efficiency
Axial flow compressors have instability region of operation
Before intercooler
After intercooler
After receiver
Between after-cooler and air receiver
Equal to
Less than
More than
None of these