Bell Ian H, Domanski Piotr A, McLinden Mark O, Linteris Gregory T
Applied Chemicals and Materials Division, National Institute of Standards and Technology, Boulder, CO, 80305, USA.
Energy and Environment Division, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA.
Int J Refrig. 2019;104. doi: 10.1016/j.ijrefrig.2019.05.035.
We investigated refrigerant blends as possible low GWP (global warming potential) alternatives for R-134a in an air-conditioning application. We carried out an extensive screening of the binary, ternary, and four-component blends possible among a list of 13 pure refrigerants comprising four hydrofluoroolefins (HFOs), eight hydrofluorocarbons (HFCs), and carbon dioxide. The screening was based on a simplified cycle model, but with the inclusion of pressure drops in the evaporator and condenser. The metrics for the evaluation were nonflammability, low GWP, high COP (coefficient of performance), and a volumetric capacity similar to the R-134a baseline system. While no mixture was ideal in all regards, we identified 16 binary and ternary blends that were nonflammable (based on a new estimation method) and with COP and capacity similar to the R-134a baseline; the tradeoff, however, was a reduction in GWP of, at most, 54% compared to R-134a. An additional seven blends that were estimated to be "marginally flammable" (ASHRAE Standard 34 classification of A2L) were identified with GWP reductions of as much as 99%. These 23 "best" blends were then simulated in a more detailed cycle model.
我们研究了制冷剂混合物，作为空调应用中R - 134a可能的低全球变暖潜能值（GWP）替代品。我们对由四种氢氟烯烃（HFOs）、八种氢氟碳化物（HFCs）和二氧化碳组成的13种纯制冷剂列表中可能的二元、三元和四元混合物进行了广泛筛选。筛选基于简化的循环模型，但包括了蒸发器和冷凝器中的压降。评估指标为不可燃性、低全球变暖潜能值、高性能系数（COP）以及与R - 134a基线系统相似的容积制冷量。虽然没有一种混合物在所有方面都是理想的，但我们确定了16种二元和三元混合物，它们不可燃（基于一种新的估算方法），且性能系数和制冷量与R - 134a基线相似；然而，与R - 134a相比，其全球变暖潜能值最多降低了54%。另外还确定了七种估计为“轻度可燃”（ASHRAE标准34分类为A2L）的混合物，其全球变暖潜能值降低了高达99%。然后在一个更详细的循环模型中对这23种“最佳”混合物进行了模拟。
