The performance of hybrid refrigerants in function proving refrigeration cycle was developed in this paper. Selection for constituent and calculation method was validated by the experiment in the cryogenic tank. and the experimental result of the hybrid refrigerants was to achieve lower temperature of below zero 100{top square bracket} for the cryogenic tank, When the state of system was steady, the suction pressure of the compressor was 0.28 MPa, the discharge pressure was 1.98 MPa. Flow rate of work substance was calculated with the series heat balance method after simplifying the cycle, the error was little and it was feasible. © Sila Science.

In this paper, a -100°C three-stage auto-cascade refrigeration system is proposed and the experimental device is established. In order to determine the impact of R50 on the refrigeration cycle, the experiments are made by using mixed-refrigerants with R134a/R23/R14 and R134a/R23/R14/R50 containing the same quantity of R134a, R23 and R14 respectively in the same device. By analyzing and comparing the different effects of the two experiments, it is found that when R50 is added into the mixed-refrigerants, the evaporation temperature and the temperature after condensation at the second-stage and the third-stage partial condensers are lower, but the high pressure is increased. The higher the hige pressure is, the more power consumption is needed and more time is required to achieve the designed temperature. So it is harmful to the cycle performance of the three-stage auto-cascade refrigeration system when R50 is added into the mixed-refrigerants.

A single-compressed and three-stage segregating auto-cascade refrigeration system was developed in this paper. System fundamentals are introduced. Circular flow of each component in the cycle was calculated with the series heat balance method, the feasibility was pointed out for selecting the proportion of mixture in the manufacturing process of actual device by calculating. The effects of operating temperatures for cryogenic tank on the temperature for evaporator, the low side of regenerator, before throttling and the pressure are slight when the state of the system is steady. © Sila Science. All Rights Reserved.

In this paper the auto-cascade refrigerating system by using mixed-refrigerant in -100°C temperature rang is proposed and the corresponding experimental device is established, then the corresponding experiments are conducted. Based on the calculation, the best ratios of three-stage and four-stage autocascade refrigeration system are respectively obtained through many experiments. Then the performance comparison of three-stage and four-stage auto-cascade refrigeration system is obtained. © Sila Science. All rights reserved.

In order to select the mixed refrigerants used in three-stage auto-cascade system, a method were proposed for choosing the component of mixture, R134a£¯R23£¯R14£¯R50 were chosen as a mixture for the equipment. After raising the hypotheses of some ideal state, the refrigeration cycle in the system was simplified. R50 was ignored having unnecessary influence on system and it was considered that there was only R134a£¯R23£¯R14 in the refrigerating cycle. Circular flow of each component in the cycle was calculated with the series heat balance method, and the best proportion of constituent of mixture according to experimental result was compared with the flow quantity of R14 as a unit, After analyzing the reason causing the error, the feasibility was pointed out for selecting the proportion of mixture in the manufacturing process of actual device by calculating.

为了确定R50对-100℃温区三级自动复叠系统中后期运行状态的影响,分别以R134a/R23/R14、R134a/R23/R14/R50为混合工质在同一台实验装置上进行两次试验,其中R134a、R23、R14组分充注量相同。通过对两组工质进行实验和对比分析,发现添加R50时第二、三级分凝器蒸发温度和冷却后温度更低,但是系统压力明显更高,设备耗能增加,达到设计温度所需时间增长,因此在-100℃温区的自动复叠系统混合组分添加R50会对系统的性能不利。

In order to select the mix refrigeration used in three-stage auto-cascade system,some notes were pointed out for choosing the component,R134a/R23/R14/R50 were chosen as a mix for the equipment.After simplifying the refrigeration cycle process in the system and giving out some suppose in ideal,R50 was ignored for not necessary and it was considered that there was only R134a/R23/R14 in the cycle.Each component cycle flow in the cycle was calculated with series heat balance method and compared with the best component ratio,which was suggested according to experiment result with the flow quantity of R14 as a unit.After analyzing the reason which caused the error,the feasibility was pointed out for selecting the mixture refrigerant component ratio in actual device manufacturing process by calculating.