The pressure ratio of an ideal vanned compressor with increase in mass flow rate :
A. increases
B. decreases
C. remains constant
D. first decreases and then increases
E. unpredictable
Actual compression curve is :
A. same as isothermal
B. same as adiabatic
C. better than isothermal and adiabatic
D. in between isothermal and adiabatic
E. none of the above
Surging phenomenon in centrifugal com-pressor depends on :
Pick up wrong statement ?
A. mass flow rate
B. pressure ratio
C. change in load
D. stagnation pressure at the outlet
Efficiency of gas turbine is increased by :
A. reheating
B. inter cooling
C. adding a regenerator
D. all of the above
The hottest point in a gas turbine is :
A. at the base
B. at the tip
C. in the centre
D. between ~ to i of the blade height
Temperature of gases at end of compression as compared to exhaust gases in a gas turbine is :
A. higher
B. lower
C. equal
D. can’t be compared
The pressure ratio in gas turbines is of the order of :
A. 2:l
b. 4:1
C. 61: 1
D. 9 : 1
The thermal efficiency of a gas turbine as compared to a diesel plant is :
A. same
B. more
C. less
D. depends on other factors
Gas turbine blades are given a rake :
A. equal to zero
B. in the direction of motion of blades
C. opposite to the direction of motion of blades
D. depending on the velocity
The air-fuel ratio in gas turbines is of the order of :
A. 7 : 1
B. 15 : 1
C. 30 : 1
D. 40 : 1
E. 50: 1
