Surging is the phenomenon of

Explanation:

Surging:

• It is unsteady, periodic and reversed flow condition in the dynamic compressor.
• Surging is a complete breakdown of steady flow through the compressor due to periodic reversal.

• This reversal of flow occurs during the closing of the valve in the operating range has a mass flow rate less than corresponding to the maximum pressure ratio.
• This reversal of flow causes the abnormal sound, vibration, a decrease in efficiency, an increase in temperature and if the intensity is more, it may lead to mechanical damage.

Stalling: 

• It is another instability in the flow of compressor that occurs nominally at the stable operating range.
• The stall may lead to noisy vibration and fatigue failure of the compressor.

Chocking: 

• The chocking occurs in the compressor which operates at low discharge pressure and maximum flow rate.