热泵工况下滚动转子式压缩机试验研究

首先对小型全封闭滚动转子式压缩机用于热泵型房间空调器的优越性进行了探讨,给出了热泵工况下压缩机的理想工作温度范围及热泵型空调压缩机气液分离器设计原则,并对依据该原则设计的不同容量样机进行了试验,对试验结果进行了处理分析。结果表明,滚动转子式压缩机能够在恶劣工况下长期安全、可靠、高效地运行,是理想的热泵空调主机。     

滚动转子式补气压缩机在热泵系统中的实验研究

介绍了滚动转子式补气压缩机的设计,并将其在热泵系统中进行了实验研究。分析了不同制热工况下滚动转子式补气压缩机的性能,对比了带闪发器与过冷器的经济器热泵系统、滚动转子式与涡旋式补气压缩机的性能。结果表明:随着室外环境温度的下降,滚动转子式补气压缩机补气后制热量提升比例逐步增大;滚动转子式补气压缩机制热实验中,带闪发器系统的制热量较高;在超低温制热工况下滚动转子式补气压缩机制热量提升18%左右,与涡旋式补气压缩机相比制热量相当,性能略高。     

太阳能空气双热源热泵测试与控制方案设计

设计一台三匹压缩机热泵实验台，将太阳能热水系统和空气源热泵结合，介绍该热泵系统的工作原理、结构。系统能够满足不同季节制冷、采暖和供热的需求，根据系统的不同工作模式，热水箱在系统的接入位置可以通过阀门进行灵活切换。为了适应不同工况的能量调节需求，采取对室外机风机和压缩机进行变频控制，并研究在无太阳能作为辅助热源的情况下风机转速和压缩机功率变化对产热能力的影响。关键词太阳能热水器空气源热泵制冷剂气体流量能量调节     

转子压缩机与涡旋压缩机的对比与发展

空气源热泵压缩机的性能是适合不同气候条件的热泵的关键。本文回顾了转子与涡旋压缩机的发展历程,早期房间空调器用压缩机为活塞式,后期出现了转子压缩机和涡旋压缩机,压缩机效率得以提升。转子式压缩机和涡旋式压缩机均向适应低环境温度工况的方向发展。介绍了影响这两种压缩机发展的关键技术,改进电机与压缩机的结构来提升压缩机效率,通过变压比、喷气增焓、部分负荷下调节等技术,提升了压缩机系统性能系数COP与综合部分负荷性能系数IPLV(H)。采用直流电机替代交流电机,可提高两种压缩机的电机效率和频率调节范围。通过对涡旋压缩机进行不对称涡旋盘设计,可减小噪音与泄漏量;对转子压缩机的双转子进行对称布置,增大了压缩机的容量。带排气阀的涡旋压缩机可在一定程度上实现变压缩比,而转子式压缩机有排气阀,在变工况方面具有明显的优势。两种压缩机均可采用喷气增焓技术,实现热泵低环境温度较大的压缩比。     

带闪蒸型经济器的风冷螺杆热泵机组性能的实验研究

研究了带闪蒸型经济器风冷螺杆热泵机组对制热性能的影响,理论分析了补气压力的变化对机组制热性能的影响。研究表明,带闪蒸型经济器热泵螺杆机组制热量随经济器的补气压力的减小而增大,压缩机功率也随经济器的补气压力的减小而增大,压缩机的COP随着经济器的补气压力的升高先升高再降低,存在最佳效率的补气压力点。实验测试了比最佳补气压力点偏高的经济器补气压力对机组性能的影响,理论计算结果和实测数据吻合良好。     

螺杆式空气源热泵机组压缩机油位试验研究

分析压缩机吸气回液、外置油分离器油分离效率对螺杆式空气源热泵机组压缩机油位的影响,提出改进翅片换热器分液、优化气液分离器结构、改善油分离器分离方式等改进措施,并对螺杆式空气源冷（热）水机组进行试验。结果表明,所提改进措施不仅能够提高压缩机运行过程中的油位,而且能够提高机组运行稳定性。     

电动汽车空调热泵型涡旋压缩机结构分析

为了解决电动汽车空调系统冬季采暖问题,针对冬季空调工况下压缩机单级压比增大的运行特性,以涡旋压缩机制热性能系数为热力学优化目标函数,确定了制冷剂循环系统中的最佳补气压力,优化了涡旋压缩机静涡旋盘上的中间补气口的几何位置和形状,使其具备了准双级压缩功能。将研发的热泵型电动涡旋压缩机安装于电动汽车空调系统,利用空气焓差法对系统进行了制热、制冷性能实验。实验结果表明,静涡旋盘结构优化后的热泵型电动涡旋压缩机,其制热和制冷能力可以满足5人座电动汽车司乘人员的冬季和夏季舒适性要求,并且具有较高的制热和制冷性能系数,从而提升了汽车空调系统热泵循环和制冷循环的热经济性,达到了节能的目的。     

直流变频空气源热泵热水器的实验研究

针对普通的定频空气源热泵热水器不能在宽负荷和宽温度条件下运行等缺陷,提出一种直流变频空气源热泵热水器.通过对样机进行实验,得出了制热量、功率、COP值、吸气温度、排气温度等性能参数随压缩机运行频率的变化规律。结果表明直流变频热泵热水器能在宽负荷、宽温度条件下稳定运行。     

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%。     

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.     

R32热泵系统排气温度控制及理论预测

根据R32在空气源热泵中的研究和应用现状,介绍系统排气温度控制的3种途径,即中间压力补气（EVI）、中间压力喷液（ELI）和吸气干度控制（SX）;提出根据压缩机效率和制冷剂物性预测排气温度的模型,得到R32在EVI,ELI和SX热泵系统的排气温度预测矩阵表,以压缩机吸、排气饱和温度分别为-20℃和40℃为例,为使得排气温度控制在100℃左右,EVI系统补气干度应约为0.90,ELI系统喷液量比率应约为9%,SX系统吸气干度应约为0.96。     

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。     

空气源热泵自然冷源过冷制热性能实验研究

冬季我国北方室外环境蕴含大量天然冷源,热力学分析表明热泵工质过冷释放的热量可以在蒸发器的等温吸热过程中获得补偿。为了研究大气自然冷源对热泵制热性能的影响,增设室外过冷器,搭建利用自然冷源过冷的空气源热泵实验装置。实验结果表明：当室外环境温度大于0 ℃,冷凝温度小于45 ℃的条件下,自然冷源过冷对热泵制热量与制热COP影响均较小,系统制热量维持在6.22 ~ 6.70 kW,制热COP维持在3.03,压缩机排气温度维持在103 ℃以下;当室外环境温度小于 -10 ℃,冷凝温度大于50 ℃时,随过冷度的增加,压缩机功率增加、排气温度显著增高,系统制热量呈先缓慢增加后减小趋势,制热COP降至2.3。基于上述研究提出一种空气源热泵过冷融霜新型除霜方式,融霜同时不停止制热。     

制冷剂R32特性及其用于空气源热泵热水器的理论循环分析

介绍R32,R22和R407C以及R410A四种制冷剂的流动特性和热力学特性,并对采用这4种制冷剂的空气源热泵热水器进行理论循环分析。从计算结果可以看出,与采用其他3种制冷剂的系统对比,采用R32制冷剂的系统具有较低的压缩比,较高的理论COP以及容积制热量;在当前阶段,R32是用于空气源热泵热水器的一种较好的制冷剂。     

兖矿鲁化28000m~3/h空分设备流程和配置的选择

根据生产实际确定气体产品的技术参数,并结合国内外空分技术水平,选择新建设的28000m3/h空分设备的流程,详细介绍了精馏塔系统和换热器系统等静止设备和空压机、液体泵等运转设备的选型经验。     

自动控制元器件在空气源热泵（冷水）机组中的应用

空气源热泵（冷水）机组以空气作为热源,释放热量或吸收热量,每个运行周期内空气温度和含湿量跨度大,水温从低到高变化大,机组运行条件恶劣,需要完善的控制。本文分析空气源热泵（冷水）机组控制中的主要难点：制冷剂流量控制、除霜、压缩机保护、换热器防冻保护。依据产品开发中自动控制元器件应用的经验,提出提高可靠性、保证能效和降低成本的方案和策略。     

Modeling of a novel spool compressor with multiple vapor refrigerant injection ports

A model of a novel rotary spool compressor has been developed to explore the effect of multiple injection ports on compressor and cycle performance. The thermodynamic model includes the effects of heat transfer and leakage and is numerically solved to predict the compressor power consumption and mass flow rate. Saturated vapor injection is modeled assuming that the injection pressures and the timing of the injection process can be controlled.The model predicts that adding a single injection port will provide a 12% increase in the cycle coefficient of performance (COP) when the compressor runs at 1907 rpm with R-22 evaporating at ?7 °C, condensing at 49 °C, and 15 °C of superheat. Adding a second, non-optimized injection port increases the COP by 16% compared to the cycle without injection. The model is used to investigate the effect of injection pressure, port location, and port diameter on cycle performance.     

Using an air cycle heat pump system with a turbocharger to supply heating for full electric vehicles

Air cycle heat pump has large potentials in heating applications. However, a key challenge faced nowadays is the matching problem between its expander and compressor. This paper presents the performance evaluation of an air cycle heat pump system integrated with a turbocharger, a blower and a regenerated heat exchanger. A thermodynamic model for this system is first developed and the relationships between the system performance and the operating parameters are investigated. Then, the performance of three different air cycle heat pumps with a blower installed before the compressor, and a blower installed before the turbine, and with an expander, are numerically simulated. The results indicated that the blower installed before the compressor can achieve a higher heating capacity and thus a higher COP. Finally, the heating power consumption of air cycle heat pump was compared with the PTC and the vapor compression heat pump of the full electric vehicle.     

可变内容积比螺杆式压缩机的性能分析

随着冷水机组、单元式空调机和水源热泵机组等产品的能效指标从名义工况EER或COP发展到IPLV或ICOP,机组的变容量或变工况性能主要取决于压缩机的变容量或变工况性能。固定内容积比的螺杆式压缩机如果在偏离设计工况下工作,效率下降,进而导致整个机组的性能下降。本文研究变内容积比螺杆式压缩机,内容积比可变化,使得压缩机内压比与外压比与工况相适应,可提升压缩机效率及机组性能。应用于冷水机组、水源热泵机组时,水源热泵机组在制冷工况时能效比可提高14.1%～35%,冷水机组的IPLV可提高7.2%左右。     

Development of capacity modulation compressor based on a two-stage rotary compressor – Part ΙΙ: Performance experiments and P–V analysis

The capacity and efficiency of a capacity modulation compressor based on a two-stage rotary compressor are studied experimentally. The test results are compared with results from a numerical analysis (Part Ι). The proposed compressor has superior performance and efficiency compared to the conventional bypass-type single-stage compressor. The results satisfy a maximum 3% error requirement for all air conditioning operational conditions. Our results show that for the power mode, the cooling capacity (1% higher than that of the bypass-type) and power consumption (3% lower than that of the bypass-type) of the two-stage rotary compressor are slightly improved. For the saving mode, the cooling capacity (10% higher than that of the bypass-type) and power consumption (8% lower than the bypass-type) are significantly improved. In addition, the results of a loss analysis based on the pressure–volume (P–V) diagram exactly matched the results of the numerical simulation.