采用涡旋压缩机的电动汽车空调准双级压缩热泵性能实验研究

为了解决电动汽车空调系统冬季采暖问题和抑制冬季恶劣工况下压缩机排气温度过高状况,本文采用补气增焓技术,设计了电动汽车准双级压缩热泵空调系统,构建了电动汽车空调准双级涡旋式压缩机性能测试实验台。采用5种不同室外环境温度工况,分别测试了单级和准双级涡旋式压缩机。结果表明:压缩机的排气温度随环境温度的降低而升高。5种工况下,单级涡旋压缩机的排气温度均高于准双级涡旋压缩机的排气温度,尤其在环境温度为-7℃时,准双级涡旋压缩机的排气温度降低了10℃。与单级涡旋压缩机相比,在低温工况下,准双级涡旋压缩机的排气质量流量提高了12.9%~17.4%,系统制热量提高了7.3%~8.3%,制热性能系数COPh提高了7.6%~8.2%。     

纯电动公交车热泵型空调系统设计与实验研究

针对纯电动公交车设计了一套热泵型空调系统,并对其运行特性进行了实验研究,分析了环境温度、压缩机转速和室内外风速对制冷/制热量、COP/EER和排气温度的影响。研究结果表明,设计的热泵型空调系统具有较好的制冷/制热性能,在制冷工况转速为2700r/min时COP最高,而制热工况下EER随转速增加而减小。在制热工况下,EER随室外风机转速增加而降低,因此较低的室外风机转速更有利于系统的节能。     

电动汽车蒸汽喷射式低温热泵空调系统性能研究

本文设计并研制了一种应用于电动汽车的新型蒸汽喷射式热泵空调系统,并将空调系统实物样机在测试台架上进行了性能试验。试验结果表明:蒸汽喷射器和中间补气涡旋压缩机的引入可有效降低压缩机排气温度。相较于PTC电加热制热方式,本文研究中热泵空调系统采暖方式最少可降低制热功耗2 169 W,最少可有效提升电动汽车的续航里程16.9%。     

带闪蒸器补气的R134a准二级压缩制冷/热泵系统实验研究

为增加空气源热泵运行的稳定性及提高其性能系数,本文提出了以R134a为工质的涡旋压缩机闪蒸器补气制冷/热泵系统。搭建了实验台对压缩机排气温度、功耗、制冷量、制热量及制冷、制热性能系数进行研究。结果表明:当冷凝温度为45℃,蒸发温度为-20~0℃时,与采用相同工质的单级系统相比,补气系统的排气温度降低了6.2℃,功耗增加1.4%~2.8%,制冷量和制冷COPc分别提高19.8%和17.6%,制热量和制热COPh分别提高15.3%和13.2%。     

电动汽车热泵空调系统设计优化及试验研究

为高效节能的满足电动汽车冬季采暖需求,本文结合电动汽车结构研制了一套蒸汽压缩式冷暖双模式热泵空调系统,将其搭载在电动汽车上进行性能试验,研究了环境温度对热泵空调系统制热性能的影响,结果表明该系统能较好的满足电动汽车冬季采暖需求。热泵空调系统性能受环境温度影响大,环境温度越低,系统制热量越少、制热效率越低。针对低温环境下热泵空调系统效率低下的情况,利用电动汽车驱动电机余热优化系统,实验对比分析两种情况下的制热性能,结果表明利用驱动电机余热对提高热泵空调系统性能有很大的帮助。     

电动客车用余热回收型热泵的换热器优化及性能实验研究

本文针对热泵空调系统在冬季低温工况下制热能力衰减问题,通过换热器设计优化,研发出基于喷射补气的余热回收型热泵空调系统,并进行了性能实验研究.结果表明:研制的准二级压缩电动客车热泵空调系统在低温条件下具有较好的制热性能.在环境温度为-20℃,车内温度为20℃,余热量为1.8 kW的制热工况下,相比于无余热回收工况,系统制...     

滑板补气滚动转子式压缩机性能试验研究

针对采用常规滚动转子式压缩机的空气源热泵系统冬季制热量不足,在极限制冷、制热工况下制热与制冷性能较差的问题,研发带有滑板补气结构的滚动转子式压缩机并对其进行测试。结果表明:与相同气缸容积的单级压缩机相比,在蒸发温度为-10℃,冷凝温度为45℃和过冷度为5℃的条件下,滑板补气滚动转子式压缩机的制热量提升12.4%,制热COP提升2%,制冷量提升13%,制冷EER提升1.3%。     

有关提高热泵型房间空调器制热能力措施的分析

本文在综合考虑制冷和制热性能的基础上,通过对影响制热能力和性能系数敏感度分析,指出以增大室内换热器的换热面积和空气循环量为主要措施,以增大室外换热器的换热面积和空气循环量为辅助措施,并注意对制冷系统中的压缩机、毛细管、储液器等各部件也做相应调整,才能最终达到提高热泵型房间空调器制热能力的目的。     

中间补气的滚动转子式压缩系统的试验研究

将带中间补气的滚动转子式压缩机应用于空气源热泵系统,不仅可解决常规系统制热工况下制热量不足的问题,而且可改善制冷工况系统性能,进一步提升系统APF值。首先介绍中间补气的滚动转子式压缩系统(中间补气系统)的工作原理,然后利用标准焓差室测试中间补气系统与单级压缩系统在不同制热工况、APF基本工况下的系统性能。试验结果表明:中间补气系统可在室外温度低于-15℃时正常安全运行,在室外温度高于-15℃时,制热量相对于单级压缩系统有较大的提高,其提高幅度均大于12%;在额定制冷和中间制冷工况下,中间补气系统开启补气时,相对于不开启补气时,其EER值分别提高8.05%和13.67%,相对于单级压缩系统,其运行频率稍有降低,EER值分别提高2.05%和0.6%;在额定制热和额定低温制热工况下,中间补气系统相对于单级压缩系统制热量与功率均有较大提高,而系统COP相差不大;在中间制热工况下,中间补气系统相对于单级压缩系统,其COP可提高7.88%中间补气系统的APF值为3.85,相对于单级压缩系统的3.68,提高幅度达4.62%。     

热泵型空调器低温制热和低温制冷的研究

热泵是一种逆向热力循环驱动热量朝向低温度介质转向的高温度介质装置。但是在热泵型空调系统当中,低温制热以及低温制冷都会产生一些负面问题,为了能够保证热泵型空调的运行效能、使用寿命。该文首先对热泵型空调进行阐述,分析热泵型空调低温制热和低温制冷问题以及措施。     

Performance evaluation of a vapor injection heat pump system for electric vehicles

Battery-powered electric vehicles (EV) need an efficient electric heating system for extending the driving mileage. An air-source heat pump system offers an economical alternative for EV because it consumes less energy than a heating system using Joule heat and it can use the same components as an air conditioning system for cooling. However, its performance degradation is inevitable at very low ambient temperatures. Although vapor refrigerant injection is known as a good technology to overcome this problem in residential heat pump systems, the number of vapor injection heat pump studies for EV applications is quite limited. In this paper, considering the characteristics of EV application, the configuration of a vapor injection heat pump system for EV is introduced, and it was modeled, using a scroll compressor geometry-based thermodynamic analysis. The performance was estimated for cold ambient regions under the EV operational conditions.     

Two-stage heat pump system with vapor-injected scroll compressor using R410A as a refrigerant

Refrigerant vapor-injection technique has been well justified to improve the performance of systems in refrigeration applications. However, it has not received much attention for air conditioning applications, particularly for air conditioning in hot climates and for heat pumping in cold climates. In this study, the performance of an 11 kW R410A heat pump system with a two-stage vapor-injected scroll compressor was experimentally investigated. The vapor-injected scroll compressor was tested with the cycle options of both flash tank and internal heat exchanger configurations. A cooling capacity gain of around 14% with 4% COP improvement at the ambient temperature of 46.1 °C and about 30% heating capacity improvement with 20% COP gain at the ambient temperature of −17.8 °C were found for the vapor-injected R410A heat pump system as compared to the conventional system which has the same compressor displacement volume.     

电动汽车热泵系统低温工况的制热性能实验研究

为研究低温时电动汽车热泵空调系统的制热性能,本文通过搭建空气源热泵空调系统实验台,实验研究了电动汽车热泵空调系统在环境温度为-10~0℃的低温工况下的制热性能,分析了压缩机转速(2000~5000 r/min)、HVAC总成进风量(300~400 m^3/h)和环境温度对该热泵系统性能的影响,最后通过推导公式,估算电动汽车在使用空调系统后的续航里程。实验结果表明:随着压缩机转速的增加,压缩机排气温度、排气压力和系统制热量均增加,而COP下降;当保持压缩机转速和环境温度不变时,HVAC总成进风量从300 m^3/h增至400 m^3/h,制热量增加约13.3%~26.0%,COP增加约0.03~0.80;在其他条件不变时,当环境温度从-10℃升至0℃,热泵空调系统的制热量增加约60.9%~71.0%,COP增加约0.51~0.63;通过公式进行计算,当环境温度为-10~0℃时,在达到相同制热量条件下,热泵空调系统可在PTC加热器的基础上使续航里程提高13.5%~20.8%。     

电动汽车热泵空调系统的试验研究

介绍研制的电动汽车热泵空调系统及其配用的双工作腔滑片压缩机的性能,依据测试样机的试验结果分析了转速对该空调系统制冷量、输入功率及COP等性能的影响。     

电动汽车用热泵空调系统设计与实验

针对纯电动汽车设计了一套蒸汽压缩式冷暖双模式热泵空调系统,并搭建了实验测试台进行了测试,对不同环境温度下系统的制热模式进行了实验分析,结果表明设计的热泵空调系统具有可行性,能在短时间内达到车室内温度需求。热泵空调的性能受外界环境的影响较大,环境温度越低,系统压力越低,压缩机排气温度越低,单位时间内制热量越少。     

Modeling and experimental evaluation of an automotive air conditioning system with a variable capacity compressor

A steady state computer simulation model has been developed for refrigeration circuits of automobile air conditioning systems. The simulation model includes a variable capacity compressor and a thermostatic expansion valve in addition to the evaporator and micro channel parallel flow condenser. An experimental bench made up of original components from the air conditioning system of a compact passenger vehicle has been developed in order to check results from the model. The refrigeration circuit was equipped with a variable capacity compressor run by an electric motor controlled by a frequency converter. Effects on system performance of such operational parameters as compressor speed, return air in the evaporator and condensing air temperatures have been experimentally evaluated and simulated by means of developed model. Model results deviate from the experimentally obtained within a 20% range though most of them are within a 10% range. Effects of the refrigerant inventory have also been experimentally evaluated with results showing no effects on system performance over a wide range of refrigerant charges.     

电动汽车引射空调系统性能实验研究

本文提出一种电动汽车引射空调系统,该系统将车内蒸发器设计成前后排分离形式,并在其间加入引射器,以提高压缩机吸气压力,形成梯级蒸发,从而优化系统性能.实验研究了在不同蒸发温度、冷凝温度工况下电动汽车引射空调系统的性能,并与传统空调系统进行了对比.实验结果表明:在不同制冷工况下,电动汽车引射空调系统性能始终优于传统空调系统...     

低温热泵用涡旋压缩机性能的试验研究

制定低温热泵用涡旋压缩机试验方案,对研制的原型机进行性能测试。试验结果表明：在冷凝温度不变的情况下,随着蒸发温度的降低,原型机的制热量有所减少,但减少的速度低于普通热泵系统用涡旋压缩机;压缩机的电功率有所增加,但增加的幅度不大,且压缩机的排气温度也有所降低,故在低温工况下采用准二级压缩热泵用涡旋压缩机比采用普通热泵用涡旋压缩机可以更有效地提高空气源热泵的低温制热性能,是寒冷地区用小型空气源热泵比较适宜采用的压缩机。     

Optimization of refrigeration system with gas-injected scroll compressor

Gas refrigerant injection has been proven as an effective method to improve the performance of the scroll compressor and its refrigeration system under high compression ratio working conditions. Much research on the injected scroll compressor and its system has been conducted, but the universal control and design method is still lacking. A model of the refrigeration system with a gas-injected scroll compressor is developed in this paper. With this model, the effects of gas injection on the system and component parameters are investigated. Based on the identified evaporator characteristics and thermodynamic analysis, a set of general principles for the design and operation of the refrigeration or heat pump system with a gas-injected scroll compressor is proposed.     

电动汽车热泵空调用双向热力膨胀阀设计

传统电动汽车空调存在制热效率低、影响汽车续航里程等缺陷,热泵空调系统是电动汽车空调发展的一个必然趋势,其关键是节流元件的选择。本文介绍的电动汽车热泵空调用双向热力膨胀阀是在现有热力膨胀阀的基础上,针对电动汽车热泵空调的特点,采用全封闭结构、二次节流、圆锥形阀芯阀口、双向工作的内密封结构等技术,解决热泵空调制冷和制热时热力膨胀阀制冷剂双向流通、流量平衡及可靠性等问题。