涡旋膨胀机研究进展及展望

A Review of Research Progress and Prospect of Scroll Expander

随着“双碳”目标的提出,涡旋膨胀机作为回收低品位能量的机械装置备受关注。首先,对近年来涡旋膨胀机的理论研究成果进行了综述,主要包括型线理论、热动力学和计算流体力学(CFD)仿真。然后,对涡旋膨胀机在有机朗肯循环(ORC)中的应用进行了总结,梳理了涡旋膨胀机在跨临界CO_(2)制冷循环中的应用研究成果。最后,对涡旋膨胀机未来的研究方向进行了展望。结果表明:变壁厚涡旋膨胀机因其可以在不增加泄漏线长度的情况下增加内容积比,因此将成为未来型线优化的主要方向;CFD仿真已成为重要的研究工具;润滑油是影响涡旋膨胀机性能的关键因素,提高润滑油的黏度有利于提升效率,而过量的润滑油则会使其性能下降;工作压力是影响涡旋膨胀机性能的最主要的因素,过膨胀、欠膨胀以及泄漏现象都会使其性能下降。此外,涡旋膨胀压缩一体机集成了膨胀机和压缩机两个功能单元于一个机壳中,显著简化了系统结构并提高了能量回收效率,是提升新能源车用CO_(2)热泵空调系统性能的有效途径。基于当前的研究成果和行业需求,提出涡旋膨胀机未来应继续深入研究和优化型线设计、减少泄漏、优化工作压力等,以满足日益增长的能量回收和环境保护需求。

With the proposal of the“carbon peaking and carbon neutrality”target,the scroll expander has garnered attention as a mechanical device for the recovery of low-grade energy.An overview of the theoretical research achievements of scroll expanders in recent years are provided,mainly including profile theory,thermodynamics,and computational fluid dynamics(CFD)simulation.Subsequently,the application of scroll expanders in organic Rankine cycles(ORC)is summarized.The application research results of scroll expanders in transcritical CO_(2) refrigeration cycles are collated.Lastly,the future research directions for scroll expanders are projected.The findings indicate that the variable wall thickness scroll expander,which can increase the volumetric ratio without lengthening the leakage path,will become the main direction for future profile optimization;CFD simulation has emerged as a significant research tool;lubricant is a key factoraffecting the performance of scroll expanders,where increasing the viscosity of the lubricant can enhance efficiency,while an excess of lubricant will reduce the performance;working pressure is the most critical factor affecting the performance of scroll expanders,with phenomena such as over-expansion,under-expansion,and leakage leading to decreased performance.Moreover,the integrated scroll compression-expansion unit,which combines the expander and compressor into one casing,significantly simplifies the system structure and improves energy recovery efficiency,proving to be an effective way to enhance the performance of CO_(2) heat pump air-conditioning systems for new energy vehicles.Based on current research achievements and industry demands,future development of scroll expanders should continue to delve into and optimize profile design,reduce leakage,and optimize working pressure,to meet the growing needs for energy recovery and environmental protection.