【摘要】 基于制冷剂-润滑油混合物管内流动沸腾局部压降实验数据,定量分析了不同质量流率下油影响因子和两相增强因子随整体油浓度、局部油浓度以及干度的变化规律,局部油浓度考虑了含油制冷剂在流动沸腾过程中的非平衡传质.研究结果表明:基于制冷剂-润滑油混合物性的两相增强因子与局部油浓度具有良好的线性相关度,不同干度下斜率变化一致性良好;基于局部油浓度和混合物性的两相增强因子压降模型能较好地反映润滑油在制冷剂中的实际存在状态及对制冷剂压降的影响规律,且物理意义明确,其预测值与95%以上实验数据的偏差均在10%以内.更多还原

【Abstract】 The variations of penalty factor and two phase multiplier with nominal oil concentration,local oil concentration and quality were analyzed at different mass flux based on experimental data of refrigerant-oil mixture.Non-equilibrium behavior of mass transfer during flow boiling of refrigerant-oil mixture was considered in calculating local oil concentration.The relationship between two phase multiplier and local oil concentration shows strong linear dependency and slope ratios at different quality are quite equivalent,while the relationship between penalty factor and nominal oil concentration,local oil concentration and quality is not pronounced.The state-of-the-art correlations of penalty factor based on nominal oil concentration and mass flux are difficult to describe oil influence on local pressure drop of refrigerant.New correlation of two phase multiplier based on refrigerant-oil mixture is developed,which approach the actual physical mechanism of refrigerant-oil and can reflect the co-existing conditions of refrigerant.It can accurately represent more than 95% of the experimental data with deviation less than ±10%.更多还原