To avoid moisture troubles, the compressed air main line should :
A. rise gradually towards the point of use
B. drop gradually towards the point of use
C. be laid vertically
D. be laid exactly horizontally
The thrust on the rotor in a centrifugal compressor is produced by :
A. radial component
B. axial component
C. tangential component
D. resultant component
A compressor at high altitude will draw :
A. more power
B. less power
C. same power
D. more/less power depending on other factors
Diffuser in a compressor is used to :
A. increase velocity
B. make the flow stream-line
C. convert pressure energy into KE
D. convert kinetic energy into pressure energy
Phenomenon of choking in compressor means :
A. no flow of air
B. fixed mass flow rate regardless of pressure ratio
C. reducing mass flow
D. increased inclination of chord w
The ratio of isentropic work to Euler work is known as :
A. pressure coefficient
B. work coefficient
C. polytropic reaction
D. slip factor
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
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
E. all 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%
E. 10%.
