| Shear cavitation is widespread in narrow gaps with relative sliding walls. This phenomenon causes the rupture of liquid film and lead to a series of issues such as wear, cavitation erosion, or large noise etc. In this thesis, the experimental study of shear cavitation was carried out by using a new Coutte rheometer developed in our group. Mainly the following aspects of work have been done.(1) The computer collected electrical motor output torque data were rectified and the correct data were obtained in order to accurately calculates the shear torque in the working section of the new Couette rheometer. The temperature measurement error was eliminated by replacing the extending cables that matches to the T Thermocouple. The problems of temperature sensor installation in the new Couette rheometer, and the removing visible small air bubbles were solved.( 2 ) The absorbed air in 500cSt dimethyl silicone oil can be quantified by using the Bunsen solubility. It is found that the viscosity of dimethyl silicone oils depends considerably on the concentration of absorbed air. Based on the Eyring's rate model, the mechanism of viscosity increase can be explained by the reduction of the free volume of silicone-oil molecules, due to the 'occupied volume' of the absorbed air molecules. A simple estimation of the 'occupied volume' of air molecules by using the Lennard-Jones potential can reasonably predict the viscosity changes in the experiment. The measurement error of the viscosity was analyzed by using error theory.( 3 ) The experiments on the influence of different air content at the saturated state on the shear cavitation inception is carried out. It is feasible to detect the shear cavitation inception by the abnormal temperature drop in the liquid. The relationship between the shear stress, cavitation index and the Bunsen solubility is obtained. It is found that the activation energy of viscosity increases before cavitation inception, yet the characteristic is remains unchanged.
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