单选题If you heard a ‘crackling’ noise in centrifugal pump, the most probable cause of the problem would be（）Ainsufficient speedBcavitationCexcess discharge pressureDexcessive net positive suction head B
单选题
If you heard a ‘crackling’ noise in centrifugal pump, the most probable cause of the problem would be（）
A
insufficient speed
B
cavitation
C
excess discharge pressure
D
excessive net positive suction head B
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