Fluid mechanics of cavitation inception in rectangular slots

John Michael Cimbala, William G. Blair

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

In order to better understand the fluid mechanics associated with cavitation inception in slots, the flow over a rectangular slot along a flat wall was studied in a non-cavitating fluid, namely air. Flow visualization experiments revealed the highly unsteady nature of the vortex-like structure(s) that developed inside the slot. Flow visualization of the slot entrance region showed that mass is transferred into the slot from the wall boundary layer; however, this mass does not appear to be drawn into the core of the primary vortex inside the slot. Direct pressure measurements inside the slot provided time-averaged contour plots of the pressure coefficient. These isobars were then used to obtain the location of the primary vortex, and also to document the minimum pressure coefficient as a function of aspect ratio. The measured pressure coefficients inside the slot are an order of magnitude lower than those for which cavitation has been observed in previous water tunnel experiments. These measurements therefore lead to question the interpretation of the previous water tunnel slot cavitation experiments. Specifically, it is likely that the previously reported cavitation was not vaporous cavitation, as had been assumed.

Original languageEnglish (US)
Title of host publicationAmerican Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED
PublisherPubl by American Soc of Mechanical Engineers (ASME)
Pages84-89
Number of pages6
Volume64
StatePublished - 1988
EventCavitation and Multiphase Flow Forum - 1988 - Cincinnati, OH, USA
Duration: Jul 24 1988Jul 28 1988

Other

OtherCavitation and Multiphase Flow Forum - 1988
CityCincinnati, OH, USA
Period7/24/887/28/88

Fingerprint

Fluid mechanics
Cavitation
Vortex flow
Flow visualization
Tunnels
Experiments
Pressure measurement
Aspect ratio
Water
Boundary layers
Fluids
Air

All Science Journal Classification (ASJC) codes

  • Engineering(all)

Cite this

Cimbala, J. M., & Blair, W. G. (1988). Fluid mechanics of cavitation inception in rectangular slots. In American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED (Vol. 64, pp. 84-89). Publ by American Soc of Mechanical Engineers (ASME).
Cimbala, John Michael ; Blair, William G. / Fluid mechanics of cavitation inception in rectangular slots. American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED. Vol. 64 Publ by American Soc of Mechanical Engineers (ASME), 1988. pp. 84-89
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Cimbala, JM & Blair, WG 1988, Fluid mechanics of cavitation inception in rectangular slots. in American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED. vol. 64, Publ by American Soc of Mechanical Engineers (ASME), pp. 84-89, Cavitation and Multiphase Flow Forum - 1988, Cincinnati, OH, USA, 7/24/88.

Fluid mechanics of cavitation inception in rectangular slots. / Cimbala, John Michael; Blair, William G.

American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED. Vol. 64 Publ by American Soc of Mechanical Engineers (ASME), 1988. p. 84-89.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Cimbala JM, Blair WG. Fluid mechanics of cavitation inception in rectangular slots. In American Society of Mechanical Engineers, Fluids Engineering Division (Publication) FED. Vol. 64. Publ by American Soc of Mechanical Engineers (ASME). 1988. p. 84-89