In the axial flow gas turbine, the work ratio is the ratio of
Compressor work and turbine work
Output and input
Actual total head temperature drop to the isentropic total head drop from total head inlet to static head outlet
Actual compressor work and theoretical compressor work
Correct Answer :
C. Actual total head temperature drop to the isentropic total head drop from total head inlet to static head outlet
Related Questions
The ratio of the volume of free air delivery per stroke to the swept volume of the piston, is known as
Compressor efficiency
Volumetric efficiency
Isothermal efficiency
Mechanical efficiency
Gas turbine blades are given a rake
Equal to zero
In the direction of motion of blades
Opposite to the direction of motion of blades
Depending on the velocity
In jet engines the products of combustion after passing through the gas turbine are discharged into
Atmosphere
Back to the compressor
Discharge nozzle
Vacuum
The thrust on the rotor in a centrifugal compressor is produced by
Radial component
Axial component
Tangential component
None of the above
The efficiency of the vane blower is (where W₁ = Workdone due to compression, and W₂ = Workdone due to back flow)
W₁/(W₁ + W₂)
W₂/(W₁ + W₂)
(W₁ + W₂)/W₁
(W₁ + W₂)/W₂
The work ratio of a gas turbine plant is defined as the ratio of
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
The working fluid in a turbine is
In two phases
In three phases
In a single phase
In the form of air and water mixture
A jet engine has
No propeller
Propeller in front
Propeller at back
Propeller on the top
In a single acting reciprocating air compressor, without clearance, the compression of air may be
Isothermal
Polytropic
Isentropic
Any one of these
The fuel consumption in gas turbines is accounted for by
Lower heating value
Higher heating value
Heating value
Higher calorific value
The inlet pressure is always ________ the discharge pressure.
Equal to
Less than
More than
None of these
Turbofan engine employs
One air stream
Two or more air streams
No air stream
Solid fuel firing
The blades of gas turbine are made of
High nickel alloy
Stainless steel
Carbon steel
High alloy steel
For slow speed large capacity compressor, following type of valve will be best suited
Poppet valve
Mechanical valve of the Corliss, sleeve, rotary or semi rotary type
Disc or feather type
Any of the above
In a centrifugal compressor, an increase in speed at a given pressure ratio causes
Increase in flow
Decrease in flow
Increase in efficiency
Increase in flow and decrease in efficiency
Separators in compressor installations are located
Before intercooler
After intercooler
After receiver
Between after-cooler and air receiver
In a jet propulsion
The propulsive matter is ejected from within the propelled body
The propulsive matter is caused to flow around the propelled body
Its functioning does not depend upon presence of air
None of the above
The efficiency and work ratio of a gas turbine plant can be increased by
Adding heat exchanger
Injecting water in/around combustion chamber
Reheating the air after partial expansion in the turbine
All of the above
The air is delivered ________ in one revolution in case of a three lobbed rotor.
Two times
Three times
Four times
Six times
The assumption made in two stage compression with intercooler is that
There is no pressure drop in the intercooler
The compression in both the cylinders is polytropic
The suction and delivery of air takes place at constant pressure
All of the above
The ratio of isentropic work to Eulers work is known as
Compressor efficiency
Isentropic efficiency
Euler's efficiency
Pressure coefficient
Pick up the wrong statement about advantages of multistage compression
Better lubrication is possible advantages of multistage
More loss of air due to leakage past the cylinder
Mechanical balance is better
Air can be cooled perfectly in between
Ramjet engine
Is self operating at zero flight speed
Is not self operating at zero flight speed
Requires no air for its operation
Produces a jet consisting of plasma
In a compressor, free air delivered is the actual volume delivered at the stated pressure reduced to
N.T.P. conditions
Intake temperature and pressure conditions
0°C and 1 kg/cm²
20°C and 1 kg/cm²
Inter-cooling in gas turbine results in
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
In a single stage, single acting reciprocating air compressor without clearance volume, the workdone is maximum during
Isothermal compression
Isentropic compression
Polytropic compression
None of these
In a closed cycle gas turbine, the air is compressed
Isothermally
Polytropically
Isentropically
None of these
Aeroplanes employ following type of compressor
Radial flow
Axial flow
Centrifugal
None of the above
Isothermal compression efficiency can be attained by running the compressor
At very high speed
At very slow speed
At average speed
At zero speed
Gas turbine works on
Brayton or Atkinson cycle
Carnot cycle
Rankine cycle
Erricson cycle