Air Compressor

Stalling of the blades of axial flow compressor is:

• an unsteady periodic and reversal of flow

• the fixed mass flow rates irrespective of pressure ratio

• the reduction of lift force at higher angle of incidence

• all of the above

Crankshaft of a reciprocating compressor is basically made of what?

• semi-steel

• aluminum alloy

• steel forging

• cast iron

An axial flow compressor is suitable for:

• high volume flow rates with small pressure rise

• low volume flow rates with low pressure rise

• high volume flow rates with high pressure rise

• low volume flow rates with high pressure rise

Modern way of detecting air compressor leak is by using

• soap and water

• air leak detector

• acoustic leak detector

• ammonia leak detector

For reciprocating compressor slip at positive or negative displacement:

An unloader is used on air compressor to:

• relieve air pressure

• start easier

• stop easier

• run faster

Most permanent installations under piston compressors available as stock items of what pressure?

• 150 psi

• 200 psi

• 250 psi

• 300 psi

As a rule of thumb, for a specified amount of compressed air, the power consumption of the compressor decrease by ____ for each 3 deg C drop in the temperature inlet air to the compressor.

• 1 percent

• 1.5 percent

• 2 percent

• 2.5 percent

Which of the following is a safety device on a compressor?

• relief valve

• strainer

• over speed shut down

• over pressure shut down

For muti-stage compression of an ideal brayton cycle, the back ratio will _______.

• increase

• decrease

• remains the same

• none of these