冷凍機潤滑油中の冷媒発泡特性に関する実験的研究

抄録

In order to improve the reliability of the refrigerant compressor, the phenomena of refrigerant foaming in lubricating oil have been examined. The nucleation conditions of refrigerant HCFC-22 are examined experimentally in 2 kinds of oils, such as alkyl-benzene oil and polyol-ester oil, which have the different molecular structure. From these experiments, it is found that there exists a critical value of the bubble growth work under which the refrigerant foaming occurs, and this value is a universal one regardless of the kind of lubricating oil, temperature and refrigerant mole solubility. On the base of the experimental results, a new empirical formula of the pressure drop for the refrigerant foaming is suggested. From this formula, it becomes possible to calculate the bubbles generating condition in arbitrary temperature and refrigerant solubility.