CAJ | 학술논문

以R134a为工质，采用包含混合室内摩擦损失的等面积混合模型，研究了两相喷射器几何结构和工况参数对压缩/喷射制冷循环性能系数(COP)、单位容积制冷量(qv)、压缩比和排气温度的影响，并与传统压缩制冷循环的性能进行对比。结果表明：喷射器存在一个最优面积比使压缩/喷射制冷循环COP和单位容积制冷量qv最大，且最优面积比值随工质的不同和工况参数的变化而变化；在相同工况参数下，以R134a为工质的喷射器最优面积比大于以R1234yf为工质的喷射器最优面积比；在相同工质和工况参数下，等面积混合模型计算的最优面积比小于等压混合模型的计算值，即在相同工质和工况参数下，按照等面积混合模型设计的喷射器外型尺寸较小；给出的以R134a和R1234yf为工质的喷射器最优面积比与冷凝温度、蒸发温度、过冷度和过热度之间的关联式，可供工程设计参考；在所进行的研究工况范围内，压缩/喷射制冷循环较传统压缩制冷循环COP最大可提高20%，单位容积制冷量qv最大可提高28%，此时冷凝温度为55℃，蒸发温度为-10℃，过冷度和过热度都为0℃，对应的喷射器最优面积比为4.5。
이R134a위공질，채용포함혼합실내마찰손실적등면적혼합모형，연구료량상분사기궤하결구화공황삼수대압축/분사제랭순배성능계수(COP)、단위용적제랭량(qv)、압축비화배기온도적영향，병여전통압축제랭순배적성능진행대비。결과표명：분사기존재일개최우면적비사압축/분사제랭순배COP화단위용적제랭량qv최대，차최우면적비치수공질적불동화공황삼수적변화이변화；재상동공황삼수하，이R134a위공질적분사기최우면적비대우이R1234yf위공질적분사기최우면적비；재상동공질화공황삼수하，등면적혼합모형계산적최우면적비소우등압혼합모형적계산치，즉재상동공질화공황삼수하，안조등면적혼합모형설계적분사기외형척촌교소；급출적이R134a화R1234yf위공질적분사기최우면적비여냉응온도、증발온도、과랭도화과열도지간적관련식，가공공정설계삼고；재소진행적연구공황범위내，압축/분사제랭순배교전통압축제랭순배COP최대가제고20%，단위용적제랭량qv최대가제고28%，차시냉응온도위55℃，증발온도위-10℃，과랭도화과열도도위0℃，대응적분사기최우면적비위4.5。
Using the constant-area model with the consideration of containing friction losses in the mixing chamber, the effects of two-phase ejector geometry and operating parameters on the coefficient of performance (COP), volumetric cooling capacity (qv), compression ratio and discharge temperature of the compression/ejection refrigeration cycle (CERC) were studied by using R134a as refrigerant. The performances of conventional compression refrigeration cycle (CRC) and CERC were compared. Results show that there exists an optimal ejector area ratio corresponding to the maximum COP andqv of the CERC system. The optimal ejector area ratio varies with the variation of refrigerant species and operating parameters. Under the some operating parametes, the optimal ejector area ratio of R134a is higher than that of R1234yf, and under the same refrigerant and testing parameters, the optimal area ratio calculated by the constant-area mixing model is lower than that calculated by the constant-pressure mixing model, which means that the physical dimension of the ejector designed by the constant-area mixing model can be smaller. The correlation formula expressing the relationships between the optimal ejector area ratio, the condensing temperature, the evaporation temperature, the supercooling degree and superheat degree was obtained for refrigerant R134a and R1234yf. This correlation formula can provide guidance in the engineering design. Within the testing conditions, the maximum improvements of COP andqv over the conventional compression refrigeration cycle are about 20% and 28% respectively with condensing temperature 55℃, evaporation temperature-10℃, supercooling degree 0℃ and superheat degree 0℃, and the optimal ejector area ratio calculated is 4.5 at this time.