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Fluid cavitation corrosion can cause severe damage and problems in many practical applications. A collapsing bubble produces pressure and thermal shock waves, and microjets. These intense local forces will erode material in the proximity of the collapsing bubble. The intensity of the collapsing bubble is heavily dependent on the physical and thermodynamic properties of the cavitating fluid medium. An experimental study of the effect of various physical and fluid thermodynamic properties of the fluid has been conducted utilizing an ultrasonic cavitation generator and a real time cavitation intensity measuring method that had been developed earlier by the author and described in reference [1]*. Tests have been conducted at room and elevated temperatures. A test matrix with fluids that have additives to modify certain physical characteristics of the fluid was established. The physical properties were either measured or calculated.

Recent engine design trends towards increasing power, reducing weight, advancing of injection timing and increasing of injection rate and pressure could result in increased incidence of liner pitting. Liner pitting due to coolant cavitation is a complex function of many engine design parameters and operating conditions as described in reference [1]*. Traditionally, liner cavitation problems were not detected early in the development cycle. Traditional liner vibration and coolant pressure measurements in conjunction with a numerous amount of expensive engine endurance tests were then needed to resolve cavitation problems. A method newly developed by the author and described in reference [2] for cavitation intensity measurements was successfully utilized to map out engine operating condition and develop limit curves. This method could also be applied in a non intrusive fashion.