摘要： 【中文摘要】 在復(fù)疊制冷實(shí)驗(yàn)臺(tái)上對(duì)由CO2/R290組成的不同配比的二元混合制冷劑進(jìn)行了低溫循環(huán)性能實(shí)驗(yàn)。實(shí)驗(yàn)結(jié)果表明,隨著CO2含量增大,二元混合物的壓比減小,制冷量增大,耗功減少,COP增加,制冷速率增大。但隨著CO2含量增大,二元混合物的排氣溫度也升高,當(dāng)CO2在混合物中的組分達(dá)到71%時(shí),蒸發(fā)溫度為-61℃時(shí),壓縮機(jī)的排氣溫度接近115℃。因此,混合物中CO2含量不宜超過(guò)71%?；旌衔镏蠷290降低了CO2凝固點(diǎn)溫度,同時(shí)也降低了CO2較高的冷凝壓力,對(duì)擴(kuò)展CO2在低溫區(qū)域的應(yīng)用很有益處。 【英文摘要】 The experiment on concentration ratio of CO2/R290 in the low-temperature circuit of a cascade refrigeration system was conducted in our study.The results show that the refrigeration capacity,the COP,and the refrigeration rate increased while the pressure ratio and the power input decreased with the increase in the CO2 concentration ratio.However,the increase in the CO2 concentration ratio resulted in the increase in the discharge temperature,and the discharge temperature of the compressor was up to 115℃ when the concentration ratio of CO2 was 71% and the evaporating temperature was-61℃.It is suggested that the concentration ratio of CO2 should not exceed 71%.In addition,R290 in the mixture could reduce the freezing point and the condensing pressure of CO2. 【中文關(guān)鍵詞】 熱工學(xué); 復(fù)疊制冷; 混合制冷劑; 低溫; 濃度配比【英文關(guān)鍵詞】 Pyrology; Cascade refrigeration; Mixture refrigerant; Low temperature; Concentration ratio