Plant characteristic curve

The plant characteristic curve graphically describes the relationship between the delivery head (HA) to be supplied by the pump and the desired delivery flow (Q). It is also referred to as piping characteristic and consists of static and dynamic components. Since the dynamic components change quadratically with the delivery height, the plant characteristic curve has a parabolic shape.                   Add Hdyn and Hstat to the graphic and insert a y-axis distance:             The static components are independent of the flow velocity. The dynamic components are determined among other things by the following factors: • Viscosity (= toughness) of the medium • flow velocity • Pipe roughness • tube length The system characteristic (pipe line characteristic) can be calculated using the following formula:                       The intersection of the system with the pump characteristic represents the operating point of the pump; here the delivery head of the pump and the systems are the same.