Abstract:

Gas engine-driven heat pump (GHP) is an advanced low-carbon, energy-saving and clean heating technology. In view of the limitations of the current commonly used in GHP system technology research, such as the lower limit of the ambient temperature of R134a refrigerant for heating mode was high and the energy efficiency of the piston compressor was low, an energy-efficient GHP experimental platform was built innovatively based on the use of R410A refrigerant and scroll compressors. The heating performance characteristics of the GHP system with waste heat recovery device at high ambient temperature were investigated. The changing laws of heating capacity (Q_h), gas consumption power (P_gas), compressor power (P_comp), primary energy ratio(PER) and coefficient of performance (COP) were obtained under the conditions of different outlet water temperature (t_w,out), engine speed (N_eng), inlet water flow rate (G_w)_{and whether the engine waste heat was recovered or not. The error analysis of the key performance parameters was carried out. The results illustrate that when tw,out increases from 41℃ to 50℃, Qh, PER and COP decrease by 3.12%, 13.17% and 18.92%, respectively. The decline extent of PER is much smaller than that of COP. When Neng increases from 1200r/min to 1800r/min, the increase of Qh, Pgas and Pcomp are 51.03%, 43.98% and 55.37% respectively at tw,out of 50℃ . Meanwhile, the increase of PER is 4.90% due to the influence of the increase of the effective thermal efficiency of engine. When Gw increases from 5.8m³/h to 11.5m³/h, the system performance parameters are not sensitive to the change of Gw. When the system undergoes waste heat recovery, Qh, PER and COP are all significantly increased, and they increase by 31.18%, 36.06% and 31.54% respectively when Neng is 1200r/min and tw,out is 41℃. The ratios of the recovered waste heat to the total heating capacity and total engine waste heat are 17.48%—24.54% and 44.16%~63.39% respectively. According to the error analysis, the errors of Qh, Pgas and PER are 3.29%, 1.00% and 3.44% respectively, indicating that the test results have high accuracy.}

Key words: gas engine-driven heat pump (GHP), heating performance, primary energy ratio, heat recovery, distributed energy resources

摘要：

燃气热泵（GHP）是一种先进的低碳节能清洁供暖技术。针对当前GHP技术研究中普遍使用的R134a冷媒制热环境温度下限偏高及活塞式压缩机能效偏低等局限，本文创新性地搭建了基于使用R410A冷媒涡旋式压缩机的高能效GHP实验平台，在实验台上进行了不同出水温度（t_w,out）、发动机转速（N_eng）、进水流量（G_w）及是否余热回收下的高温制热特性研究，得到了制热量（Q_h）、耗气功率（P_gas）、压机功率（P_comp）、一次能源利用率（PER）及性能系数（COP）的变化规律，并对关键性能参数进行了误差分析。结果表明，t_w,out由41℃增至50℃时，Q_h、PER和COP分别减小了3.12%、13.17%和18.92%，PER下降的幅度明显小于COP；N_eng从1200r/min增至1800r/min时，在50℃出水下Q_h、P_gas与P_comp分别增加了51.03%、43.98%和55.37%，PER因受到发动机有效热效率升高的影响而增加了4.90%；G_w从5.8m³/h增至11.5m³/h时，系统各性能参数随G_w变化不敏感；系统考虑余热回收后，Q_h、PER与COP均显著增加，在N_eng为1200r/min且41℃出水下分别增加了31.18%、36.06%与31.54%，系统余热回收量占总制热量和发动机总余热量的比例分别为17.48%~24.54%和44.16%~63.39%。由误差分析可得Q_h、P_gas和PER的误差分别为3.29%、1.00%和3.44%，表明了系统测试结果具有较高的准确度。

关键词: 燃气热泵, 制热性能, 一次能源利用率, 热回收, 分布式能源