Centrifugal pump outlet pressure

Pump head refers to the total head generated by the pump. The value is equal to the algebraic difference between the total head at the pump outlet and the total head at the inlet. Head is generally denoted by H, with the common unit of measurement being meters (m). The head of a water pump refers to the energy gained by a unit weight of liquid as it passes through the pump; it includes components such as potential energy, pressure energy, and kinetic energy, so the outlet pressure is only one part of it. Under normal circumstances, the proportion of pressure energy in the head is much larger than that of other forms of energy; therefore, in practical engineering applications, the outlet pressure can be used to roughly estimate the head, thereby assessing the performance of the pump.

The operating point of the pump is determined by the device’s characteristic curve. The pump outlet pressure is equal to the inlet pressure plus the pressure resulting from the head conversion. P=ρgH; according to this formula, density and head are the factors that affect pressure. Head is related to the viscosity of the medium; higher viscosity results in a lower head. For pumps, both the impeller diameter and rotational speed affect the pump’s head.

In other words, if the flow rate increases, the head decreases, which indirectly reduces the pressure? What factors affect the outlet pressure of a centrifugal pump? How to influence

This post was last edited by longziyun on 2019-1-10 at 12:54. The two people above have already covered everything comprehensively from theoretical aspects, the properties of the equipment, and the impact of materials. Answering the original poster’s question: 1. With the pump outlet valve closed, (pump outlet pressure – pump inlet pressure) / medium density = actual head ； 2. The pump outlet pressure is not only related to the properties of the equipment and the characteristics of the medium as mentioned earlier, but it is also greatly influenced by the operational conditions during equipment operation. After all, the outlet valve cannot remain closed all the time; there are many factors at play, such as the backpressure, the diameter of the pipelines, the opening degree of the control valves (resulting in pressure drops), the pressure drops in heat exchange equipment, changes in the temperature of the medium, and phase changes caused by these temperature variations. In short, one must gradually explore and think about these issues through practical experience.

The head of a pump is generally a technical parameter of the pump determined during standard water tests; it depends on factors such as the quality of the medium, its density and viscosity, as well as the rotation speed of the pump.