Abstract:A sealing leakage test system for gas-liquid mixtures was developed to measure oil leakage from shaft seals on large marine diesel engine crankcases. The air and oil leakage rates were then measured for various rotational speeds and the leakage reducing function of the oil slinger, labyrinth grooves and oil return channels were studied quantitatively. A brush seal design was then developed that was appropriate for the large shaft diameters and large clearances in crankcase shaft seals. A porous media model of the brush seal was then used to analyze the influence of the brush seal on the leakage and the flow field. The effect of the brush seal on the leakage was also studied on the sealing leakage test system. The results show that the brush seal reduces the air leakage rate by 76% and the oil leakage rate by 79%.
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