What factors will affect the efficiency of the water pump?

2020-11-06

The water pump is a device for energy conversion. We all know that there will be energy loss in the energy conversion process. Therefore, high energy loss indicates low efficiency of the equipment. So how to improve the efficiency of the pump? What factors will affect the efficiency of the pump? First, let's understand the three main aspects of pump energy loss.

1. Mechanical loss
Mechanical loss, mainly due to the energy loss formed by the friction between the liquid and the front and rear cover plates of the impeller and the pump cavity. In the energy loss of the water pump, the mechanical loss accounts for a relatively large amount, which can reach 30% of the effective power.
The outer diameter of the impeller is proportional to the loss of the disc. However, under a certain head, the loss of the disc increases with the increase in speed, and the outer diameter of the impeller decreases accordingly. This is one of the reasons for the development of high-speed pumps.
2. Volume loss
Due to the gap of the seal ring in the water pump, part of the liquid of the impeller leaks back to the impeller inlet through the gap of the impeller seal ring to cause loss. However, due to processing and assembly reasons, and too small gaps may cause jamming, so the loss of volume is also an inevitable loss.
3. Hydraulic loss
The hydraulic loss of the pump refers to the loss caused by the change of the direction of the water flow when the medium in the pump passes through the flow part. In order to reduce the friction, the smoothness of the flow parts can be improved, and the high-quality hydraulic model should be used as much as possible.