Characteristics of a series-connected two-evaporator refrigerating system

The analytical results show that the mass flow rate of refrigerant (m˙r) is primarily affected by the condensing pressure, length of the high-temperature capillary tube, and the subcooling of refrigerant, while the heat transfer coefficients of refrigerant in the evaporators (hcH and hcL) are affected by the condensing pressure and the logarithmic-mean temperature difference of the specific evaporator. However, hcH and hcL are also affected by the lengths of the low- and high-temperature capillary tube, respectively. Additionally, the ratio of the cooling capacity of the high-temperature evaporator to the total capacity (α) is primarily affected by the condensing pressure and the logarithmic-mean temperature difference of both evaporators. The differences between the calculated and experimental data are between −4% and +5%, −16% and +16%, −12% and +16%, and −10% and +10% for m˙r, hcH, hcL, and α, respectively.