The refrigerant charging quantity has significant effect on the performance of a refrigeration system. For a specific mixed refrigerant (MR) Joule-Thomson cooler

proper MR charging quantity is determined by operation pressure

temperature and concentration of components. It is difficult to determine the optimal MR charging quantity by means of experimental test

so a MR mass charge prediction model is established in this paper. Using the integral method

the Linde-Hampson cooler is divided into four parts to calculate the MR mass distribution and the liquid hold-up. The calculation result shows that

over 60% of the MR is accumulated in the hot steam of the recuperative heat exchanger

the liquid MR occupies more than 80% of the total charging quantity

and the mass of liquid MR will increase as the refrigerating temperature decreases. An experimental investigation is used to verify the accuracy of this model. The result shows that

in the refrigeration temperature of -100-60℃

the deviation between the calculated MR charging quantity and actual one is not more than 20%. The deviation between the calculated proportion of components and the experimental result is also less than 20%.