If a pump is positioned above the liquid surface, what helps in pushing fluid into the pump?

When a pump is positioned above the liquid surface, it relies on atmospheric pressure to push fluid into the pump. Atmospheric pressure acts on the surface of the liquid in the reservoir or tank. This force helps to drive the liquid upward into the pump as the pump creates a vacuum or lower pressure within itself.

The principle behind this operation is based on the fact that fluids flow from areas of higher pressure to areas of lower pressure. Since the pump is located above the fluid, the atmospheric pressure pressing down on the liquid is what allows the liquid to rise up into the pump, overcoming the gravitational pull on the liquid column.

This concept of utilizing atmospheric pressure is critical in applications where the pump is installed in such a way that it cannot rely solely on the fluid’s own kinetic energy or pressure to reach the inlet. Understanding this mechanism is fundamental for operating and troubleshooting hydraulic systems effectively.