What is the relationship between the impeller and head?
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This post was last edited by Zhenxun Bingyi on 2020-10-16 09:31. 1. Under identical conditions, for impellers made of the same material and of the same size, in the same pump and at the same flow rate, what impact does the number of impeller blades have on the head? 2. Under identical conditions, for impellers of the same material and size in the same pump, at the same flow rate, what is the effect of the impeller being closed, semi-open, or fully open on the head?
This post was last edited by ZhenXunBingYi on 2020-10-16 at 15:46. Currently, it is known that in multi-stage pumps, the heads add up; the greater the number of blades, the higher the head. For single-stage pumps, this remains unknown. I humbly request guidance from experts
Hehe, it’s like a comprehensive guide to impellers. 1. When there are more blades, it is also necessary to consider whether this affects the flow area of the channel, as well as the rotor’s own weight. 2. Their uses differ; the impeller with an open design is the lightest, while the closed-type impeller is the heaviest. There is also the factor of axial force,,,。 It is best to understand it from the perspective of its uses, as that is the most practical approach. For reference.
1. When the flow rate is the same and the impeller shape is identical, it depends on the hydraulic design of the blades themselves. If the hydraulic design is the same, the more blades there are, the higher the head will be; however, this affects both the flow rate and efficiency. 2. Generally, closed type > semi-open type > fully open type
? In terms of efficiency, closed systems are the highest, while open systems are the lowest
The more blades there are, the more efficient the operation is, and the higher the head pressure; however, more blades result in greater losses, lower efficiency, and severe crowding at the inlet. For a given impeller, there is an optimal range of blade counts
The open and semi-open types are mainly used in applications involving particles; the variation in the side clearance has a significant impact on the pump’s performance. Closed impellers, on the other hand, exhibit stable performance, which is why they are more advantageous for handling single-phase liquids