Phenomenon of choking in compressor means __________________?
(A) no flow of air
(B) fixed mass flow rate regardless of pressure ratio
(C) reducing mass flow rate with increase in pressure ratio
(D) increased inclination of chord with air steam
(D) does not occur
The ratio of isentropic work to Euler work is known as_____________________?
(A) pressure coefficient
(B) work coefficient
(C) polytropic reaction
(D) slip factor
(D) compressor efficiency
The indicated work per unit mass of air delivered is___________________?
(A) directly proportional to clearance volume
(B) greatly affected by clearance volume
(C) not affected by clearance volume
(D) inversely proportional to clearance volume
As the value of index ‘«’ is decreased, the volumetric efficiency will___________________?
(A) increase
(B) decrease
(C) remain unaffected
(D) may increase/decrease depending on compressor clearance
(D) none of the above
The advantage of multistage compression over single stage compression is ________________?
(A) lower power consumption per unit of air delivered
(B) higher volumetric efficiency
(C) decreased discharge temperature
(D) moisture free air
(D) all of the above
In a compressor, free air delivered is the actual volume delivered at the stated pressure reduced to ____________________?
(A) N.T.P. conditions
(B) intake temperature and pressure conditions
(C) 0°C and 1 kg/cm2
(D) 20°C and 1 kg/cm2
(D) none of the above
The volumetric efficiency of a compressor falls roughly as follows for every 100 m increase in elevation___________________?
(A) 0.1%
(B) 0.5%
(C) 1.0%
(D) 5%
(D) 10%.
During base load operation, the best method of controlling compressor is ___________________?
(A) start-stop motor
(B) constant speed unloader
(C) relief valve
(D) variable speed
(D) none of the above
The ratio of isentropic work to euler’s work is known as _____________________?
(A) compressor efficiency
(B) isentropic efficiency
(C) Euler’s efficiency
(D) pressure coefficient
(D) pressure ratio
The ratio of outlet whirl velocity to blade velocity in case of centrifugal compressor is called__________________?
(A) slip factor
(B) velocity factor
(C) velocity coefficient
(D) blade effectiveness