Mechanical Engineering - Compressors, Gas Dynamics and Gas Turbines - Discussion

Pressure decreed as height increases Due to low suction pressure compressor will require more power.

At elevated altitudes, lower atmospheric pressure means that the air molecules are less tightly packed together and therefore have a lower density. When an air compressor draws in air as part of its intake process it's typically a fixed volume of air so if the air density is less it means that there is fewer air molecules drawn into the compressor's cylinders/rotor lobes/vanes. Less air drawn in means less air compressed and less air delivered to the receiver tank and tools per compression cycle.

So as per question, JUST TO RUN COMPRESSOR, LESSER POWER IS REQUIRED, WHICH IS CORRECT.

At high altitude, the less power will require because compression ratio will be less.

So Answer B is correct.

Answer "B" is correct. Less power will be required by the compressor to compress the air as the density of the air/air pressure reduces at higher altitudes.

At higher altitudes molecules of air are few, hence a compressor supplies smaller volume of air at a higher altitude so it requires less power.