In modern condensers of air conditioning systems, heat pumps, evaporators seawater desalination and heaters power plants, the process vapour condensation is carried out mainly inside horizontal tubes channels. Heat transfer processes occurring in have a significant effect on overall energy efficiency mentioned systems. this paper, experimental investigation during freons R22, R406a, R407c plain...

This paper investigates the selection of best suitable eco-friendly organic and in-organic refrigerants for heating, ventilation, air conditioning (HVAC) renewable energy devices. Inorganic are used to cool devices, such as solar cells, photovoltaics, electronic Owing community’s importance, development in this area has rapidly improved over past few years. R134a, R404, R717 have become most HV...

Several media report highlight on that the pharmaceutical companies require ultra-low temperatures -80°C to transport and store its COVID-19 vaccines. This research presents thermodynamic analysis cascade refrigeration system (CRS) with several refrigerant pairs which are R32/R170, R123/R170, R134a/R170, R404A/R170, R407c/R170, R410/R170, hydrocarbon (HC) pair Propane/Ethane, namely R290/R170. ...

This paper presents the simulation study and comparison of C02 and R502 as refrigerants. At first, as a single stage vapor compression refrigeration cycle's refrigerant, C02 can be used in subcritical and transcritical situations. The performances are studied completely. The results show that C02 has the same or better performance compared to R502's in certain temperature ranges. Finally C02 an...

Refrigeration oil and other materials used with refrigerant for refrigerators or air conditioners should have thermal and chemical stability to maintain the system reliability. Some kinds of synthetic oil are used for alternative refrigerant, HFC’s and hydrolysis, material compatibility, and low-temperature extraction of contaminant or sludge are important subjects. Much more numbers and times ...

Per Lundqvist Dr., Lars Herbe M.Sc, The Royal Institute ofTechnology, Dept. of Energy Technology, S-100 44, Stockholm, Sweden Fax: +46 8 20 30 07 Tel: +46 8 790 74 52 Email: [email protected] There are several important issues when dealing with new refrigerants in a retrofit situation. This paper is however restricted to system performance and a discussion of methods suitable to determine ...

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...

Compressor reliability and durability testing has historically required significant time and a variety oftest methods, including basic materials and lubricants testing using Falex test methods or equivalent, long term compressor bench tests, end product reliability tests and final field trials before production release. Reducing the total design cycle time to a minimum, while maintaining a high...