What is pressure head?

Pressure head is a term used in fluid mechanics to describe the amount of potential energy that a fluid possesses due to its pressure. It is typically measured in units of length, such as meters or feet.

Pressure head is derived from Bernoulli's equation, which states that the sum of the pressure, kinetic energy, and potential energy per unit volume of a fluid remains constant along a streamline. By rearranging this equation, the pressure head can be calculated by dividing the pressure by the weight density of the fluid.

Pressure head is important in many applications of fluid mechanics, such as in the design of pipes, hydraulic systems, pumps, and turbines. It helps determine the pressure difference required to move fluids through pipes, the efficiency of pumps and turbines, and the height to which a fluid can be lifted. For example, in a water supply system, the pressure head is used to calculate the required pressure at the source to deliver water to a desired height in a building.

In hydrology, pressure head is also used to describe the elevation or height of the groundwater table. It represents the potential energy that groundwater has due to its pressure. Monitoring the pressure head can help in assessing the health and dynamics of aquifers, as well as in predicting the movement of contaminants in the subsurface.

In summary, pressure head is a term used in fluid mechanics to describe the potential energy of a fluid due to its pressure. It is an important parameter in various engineering and scientific applications involving fluids.