R32具有优良环保和热力循环性能，它可实现50%以上的CO2当量削减，目前提出的替代混合工质80%都包含R32，我国已将R32作为主要的替代工质。R32新型匹配润滑油在克服传统润滑油问题的同时，亦增加了R32/润滑油混合流体在传输、传热过程中的复杂性：高粘度油品对混合物的物性有着特殊的影响；另一方面，R32制冷系统高温高压特点会使润滑油对系统性能的影响更为复杂。针对上述问题，本课题通过理论分析和实验研究相结合、单管基础试验与制冷系统试验相结合的方法，探究润滑油对R32管内流动传热和压降的影响机理，建立R32/润滑油混合物管内流动传热和压降的定量关联式。同时，基于力学分析总结R32制冷系统润滑油传输与滞留机制，建立系统各部件滞油量的数学模型；揭示润滑油滞留对传热、压降的耦合影响机理。研究将建立R32与润滑油传热、输运耦合作用理论，为R32制冷空调系统的优化设计、运行提供基础理论和数据支持。

R32 is an alternative refrigerant in the R&AC industry with excellent environmental protection performance and thermal performance. R32 can achieve more than 50% reduction of CO2, so 80% of the proposed alternative mixed working medium contains R32 and R32 has been regarded as the main alternative refrigerant in China. New type lubricants for R32 have overcome difficulties of traditional lubricants, at the same time, they increase the complexity of R32/lubricant mixture fluid in the process of transport and heat transfer. The physical properties of lubricants with high viscosity become very particular. On the other hand, condensation temperature and pressure of R32 refrigeration is very high, which makes the lubricant influence on the system performance more unpredictable. This project will be conducted with the combination of theory analysis and experimental study. The effect of lubricant on heat transfer and pressure drop performance of R32 flow inside single tube will be investigated and correlations will be developed. Moreover, principle of oil transport and retention in R32 refrigeration system will be studied based on force balance analysis. The project will also attempt to establish mathmatical model of lubricant retention in components of R32 refrigeration system and explore the coupling influence of lubricant retention on heat transfer and pressure drop. The research results could not only establish coupling theory of transport and heat transfer of R32/lubricant mixture but also provide theory and data support for high-efficiency operation of R32 refrigeration system.