What is total dynamic head? Why is it important?
Total dynamic head (TDH) is a measure of how much force your pump needs to exert to move water. TDH is a combination of hydraulic head and friction loss. Hydraulic head is the force required to lift water against gravity. Water in any section of pipe is weighed down by all the water above it. The further your water inlet is below your outlet, the more hydraulic head (measured in metres, kilopascals or pounds per square inch) needs to be overcome. Friction loss refers to the fact that as water moves through a pipe, it has to slide along the walls of the pipe. Although water is slippery, there is still some friction to be overcome. The smaller the pipe diameter, the faster the water is moving. Therefore, more friction loss is experienced and the pump requires more power to operate effectively. The situation is complicated by turbulence in the water at high flow rates, and the presence of any elbows in your pipe system, where water must change direction quickly.
