A control volume has an inlet area of 0.1 m2 and exit area of 0.05 m2. The density is 3.89 kg/m2 and constant. If the inlet velocity is 30 m/s, the force on the control volume will be
A.50 N
B.150 N
C.250 N
D.350 N
Category: Turbo machines Mcqs
A diffuser
A.converts kinetic energy into thermal energy
B.converts potential energy into kinetic energy
C.converts pressure energy into kinetic energy
D.converts thermal energy into kinetic energy
In a nozzle, once the critical conditions are achieved at the throat, than which of the following remains constant:
A.Density of fluid
B.Velocity of fluid
C.Flow rate
D.All of the above
An axial flow compressor has
A.larger blades at gas entry and smaller blades at exit
B.smaller blades at gas entry and larger blades at exit
C.identical dlades at exit as well as entry
D.size of blades remains same only angles changes
As there is plenty of time for heat transfer across the walls, the flow in long pipes at low velocities attains
A.isentropic conditions
B.adiabatic conditions
C.isothermal conditions
D.polytropic conditions
Which type of rotary compressor is used in oil fired furnaces?
A.Sliding vane type blower
B.Screw compressor
C.Axial flow compressor
D.Centrifugal blower
Actual gas turbine cycle is different from ideal cycle because
A.of internal irreversibility of the process due to friction, turbulence, etc.
B.of variation of specific heats with temperature
C.of losses due to incomplete combustion
D.all of the above
In a nozzle under choked flow conditions pressure waves travel, in the divergent portion, at
A.subsonic speed
B.sonic speed
C.supersonic speed
D.subsonic to supersonic speed
Bleeding in steam turbine refers to
A.leakage of steam through bearings
B.leakage of steam through packings
C.purposely withdrawn steam for process application
D.purposely withdrawn for feed water heating
Which of the following is the least efficient method of governing steam turbines?
A.Nozzle control governing
B.Throttle governing
C.Bypass governing
D.Combined throttle and nozzle governing
