الفهرس 
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Abstract
Cavitation inception in turbulent separated flow over blunt-faced flat
plates and behind two-dimensional normal flat plates has been investigated
experimentally. The study includes numerical simulation of noncavitating
steady incompressible turbulent flow around the plates. Three blunt-faced
plates of different thicknesses and three normal plates of different heights
have been tested. The experiments were carried out in the test section of a
water tunnel. The tunnel newly built at the Faculty of Engineering, Minia
University, Minia, Egypt. Cavitation inception has been detected visually by
watching the occurrence of a few minute bubbles, namely when cavitation
was already macroscopic. The cavitation aspects were photographed
simultaneously with the corresponding flow-measurements using a digital
camera. The photos were later processed through a computer software and
printed. The dissolved gas content has been measured by a dissolved gas
content meter. Experimental observations have clearly shown that the first
traces of cavitation appear as a series of small discrete bubbles in the free
shear layer away from the solid surface near the leading edge of the bluntfaced
plates and immediately behind the upper and lower edges of the normal
plates. The cavitation inception indices tend to decrease with increasing
freestream velocity. The physical appearance of cavitation and the trend of
cavitation inception indices suggesting that it is related to the small-scale
vortices and associated large pressure fluctuations. The high audible sound
associated with the inception implies that the cavitation is vaporous. It was
also found that both the blunt-faced plate thickness and the normal plate
height have no effect on the cavitation inception indices.