Compressors, Gas Turbines and Jet Engines
The overall isothermal efficiency of the compressor is defined as the ratio of

Work required to compress the air isothermally to the actual work required to compress the air for the same pressure ratio
Volume of free air delivery per stroke to the swept volume of the piston
Isothermal power to the shaft power or B.P. of the motor or engine required to drive the compressor
Isentropic power to the power required to drive the compressor

ANSWER DOWNLOAD EXAMIANS APP

Compressors, Gas Turbines and Jet Engines
If p₁, is the pressure of air entering the L.P. cylinder and p₂ is the pressure of air leaving the L.P. cylinder (or inter-cooler pressure), then the ratio of cylinder diameters for a single acting, two stage reciprocating air compressor with complete intercooling is given by (where D₁ = Dia. of L.P. cylinder, and D₂ = Dia. of H.P. cylinder)

D₁/D₂ = p₁/p₂
D₁/D₂ = p₂/p₁
None of these
D₁/D₂ = p₁ p₂

ANSWER DOWNLOAD EXAMIANS APP

Compressors, Gas Turbines and Jet Engines
Clearance volume in actual reciprocating compressors is essential

To provide cushioning effect and also to avoid mechanical bang of piston with cylinder head
To accommodate Valves in the cylinder head
To attain high volumetric efficiency
To provide cushioning effect

ANSWER DOWNLOAD EXAMIANS APP