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渣漿泵汽蝕相似定律與汽蝕比轉速
    在設計和使用離心泵時，對幾何相似的泵，除應考慮流量、揚程、功率間的相似關系外，還應考慮汽蝕性能的相似關系。用汽蝕相似定律及汽蝕比轉速來關聯泵的汽蝕性能與設計參數。汽蝕比轉速的大小可反映該系列泵的抗汽蝕性能。
1.汽蝕相似定律
模型泵與原型泵必需的汽蝕余量之比為：

對于同一臺泵(D'=D)，當轉速變化時,泵所必需的汽蝕余量按式(1-62)計算:

從式(1- 62)可以看出，當轉速增大1倍時,泵所必需的汽蝕余量增大3倍，渣漿泵的抗汽蝕性能急劇下降，因此，若用增加轉速的方法來提高泵的單級揚程，必須考慮泵的抗汽蝕性能。高速泵一般裝有前置誘導輪 ，就是解決此矛盾的一種方法。

Cavitation similarity law and specific speed of slurry pump

In the design and use of centrifugal pumps, for pumps with similar geometry, in addition to the similarity between flow, head and power, the similarity between cavitation performance should also be considered. The similarity law of cavitation and specific speed of cavitation are used to correlate the cavitation performance and design parameters of the pump. The specific speed of cavitation can reflect the anti cavitation performance of this series of pumps.

1. Cavitation similarity law

The ratio of NPSH required for model pump and prototype pump is:

For the same pump (d '= D), when the speed changes, the necessary NPSH of the pump is calculated according to formula (1-62):

From formula (1-62), it can be seen that when the speed is doubled, the necessary NPSH of the pump increases by three times, and the anti cavitation performance of the slurry pump drops sharply. Therefore, if the speed is increased to improve the single-stage head of the pump, the anti cavitation performance of the pump must be considered. The high-speed pump is generally equipped with a front inducer, which is a way to solve this contradiction.