[PDF] Experimental And Theoretical Investigations Of Cavitation In Water eBook

Author : Jakob Ackeret
Publisher :
Page : 53 pages
File Size : 37,29 MB
Release : 1945
Category : Cavitation
ISBN :

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The cavitation in nozzles on airfoils of various shape and on a sphere are experimentally investigated. The limits of cavitation and the extension of the zone of the bubbles in different stages of cavitation are photographically established. The pressure in the bubble area is constant and very low, jumping to high values at the end of the area. The analogy with the gas compression shock is adduced and discussed. The collapse of the bubbles under compression shock produces very high pressures internally, which must be contributory factors to corrosion. The pressure required for purely mechanical corrosion is also discussed.

Author : Virgil E. Johnson
Publisher :
Page : 104 pages
File Size : 19,33 MB
Release : 1957
Category : Aerodynamics
ISBN :

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Abstract: The existing two-dimensional theory for the characteristics of supercavitating hydrofoils operating at zero cavitation number is modified to include the effects of camber, aspect ratio, and depth of submersion. For a comparison with the theory, two aspect-ratio-1 hydrofoils, a flat plate and one with a cambered lower surface, were tested by operating them near the water surface so that their upper surfaces were completely ventilated. The data obtained verified the theory to within 3 percent. Some experimental data are also presented for the models operating at nonzero cavitation number for both air and water-vapor-filled cavities.

Author : Donald S. Weir
Publisher :
Page : 130 pages
File Size : 35,2 MB
Release : 1975
Category :
ISBN :

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The results of an experimental and theoretical investigation of thermodynamic effects on developed cavitation are presented. Distributions of temperature and pressure were measured for zero- and quarter-caliber ogives over a wide range of velocities, temperatures and cavity lengths. The semi-empirical entrainment theory is used to correlate the measured temperature depressions in the cavity. This theory relates the maximum temperature depression expressed in dimensionless form as the Jakob number in terms of the dimensionless numbers of Nusselt, Reynolds, Froude, and Peclet, and dimensionless cavity length. The results show that, in general, the temperature depression increases with cavity lengths and temperature.