fixing an inducer to combat cavitation in pump
fixing an inducer to combat cavitation in pump
(OP)
Dear Forum Members
I understand that an eqpt/device fitted in the suction side of a pump can effectively handle cavitation/insuffient NPSH.
Can any one explain about Inducer?
Thank you,
I understand that an eqpt/device fitted in the suction side of a pump can effectively handle cavitation/insuffient NPSH.
Can any one explain about Inducer?
Thank you,





RE: fixing an inducer to combat cavitation in pump
An inducer stage is designed for very low npshr, it basically feeds the npshr of the stages above it. It is an invalueable tool when the npsha is low such as a condensate pump. It also allows you to shorten condensate pump and barrel. Johnston's Q-model's are inducers I'm not aware of other inducer MFR'S.
Goodluck, Flowman
RE: fixing an inducer to combat cavitation in pump
"Should the available NPSH be so low that the required suction specific speed is above about 18,000, then a separate axial flow impeller of special design - an inducer - is used ahead of the centrifugal impeller. Its flow angle is typically between 5 and 10 degrees. The vane angle is about 3 to 5 degrees larger. The number of vanes is often only two, and not more than four. The vane thickness is made as small as possible."
RE: fixing an inducer to combat cavitation in pump
The discharge pressure of the pump with inducer doesn't change at large flow rates. At lower flow rates towards shutoff the head rises a bit, and pumps with flat or drooping characteristic curves may have a shape uplift making these a bit more steep and amenable to some users.
Since it causes prerotation a careful match between inducer and suction impeller is required.
RE: fixing an inducer to combat cavitation in pump
Lakshminarayana,B.(1982), "Fluid Dynamics of Inducers - A Review, Trans. ASME, J. of Fluids Engineering, Vol. 104, December, pp.411-427
This may be obtainable from the ASME Library.