Exergy-based methods provide engineers with the best information respect to options for improving overall thermodynamic efficiency of an energy conversion system. This paper presents results advanced exergy analysis air-to-water reversible heat pump whose performance was analyzed different working fluids. Environmentally deleterious refrigerants, i.e., R410A and R134a (baselines), their eco-fri...

Abstract In the last decades, industry of HVAC&R has faced continuous changes trying to identify environmentally friendly refrigerants for numerous applications sector. However, amount low GWP fluids still available as potential is limited some natural and, among synthetic chemicals, hydrofluoroolefins (HFO). The knowledge thermophysical properties these compounds and evaluation their energ...

The use of a binary cycle coupled to the complete reinjection non-condensable gases could provide valid answer improvement sustainability geothermal plants. In recent years, interest in CO2 as working fluid transcritical cycles has increased. However, low critical temperature carbon dioxide (?30 °C) requires cooling cycle, temperatures below 15 °C, which are not always available. this work, ove...

自从《蒙特利尔议定书》基加利修正案签订并实施以来，削减当量碳排放、有效延缓全球变暖成为了各个行业的热门话题，而新能源车的快速发展也标志着交通领域的能源结构变革。不过，新能源车目前仍存在安全隐患、里程焦虑、热管理工质温室效应等瓶颈问题，这也从“节能”与“环保”两个方面对车辆热管理行业提出了更高级、更精准的要求。从节能角度来说，本文总结了热管理系统从常规单冷空调技术到热泵空调技术的系统架构转变与实现形式升级，达到了在冬季制热条件下节省大量PTC电加热能耗的目的；同时，展示了一体化热管理新概念与各种智能优化控制算法的结合，使得乘员舱、电池、电机、电控部分的综合热管理持续向着性能更优、能耗更小的方向演化；另一方面，新能源汽车热管理系统目前仍广泛使用HFC类强温室效应气体（如R134a与R407C）作为制冷剂，从环保角度出发，本文介绍了几种较为热门的环保型制冷剂替代方案，如CO2，R290，R...