Lack of control of the environment is often pinpointed as a cause of frustration and stress in confined animals. When the animal cannot control things, such as the feeding time or the lighting program, and when it cannot escape from things it finds unpleasant, it often behaves in a manner that indicates frustration.
Cavitation can also cause excessive pump vibration, which could damage pump bearings, wearing rings, and seals. A small number of centrifugal pumps are designed to operate under conditions where cavitation is unavoidable.
This phenomenon is also called CAVITATION. The vapour formed as small bubbles at the suction side collapse more or less suddenly when the liquid moves through the impeller to a high-pressure region. The formation of vapour has a marked reduction in total head and capacity of the pump.ence for this type of pumps the NPSH (R)for a lighter fluid would be more than that required for a heavier liquid in terms of the head of liquid pumped. T he flow to a reciprocating pump is cyclic then NPSH (R) shall be based on the âmaximumâ or worst condition of acceleration and flow.