A new method to calculate the pressure drop loss of the regenerator in VM refrigerator

• Pressure drop loss due to converting to heat is the first part of pressure drop loss.
• Pressure drop loss due to decreasing pressure ratio is the second part of pressure drop loss.
• The first part loss is the main part, but the second part cannot be neglected.
• The first part loss is 0.449 W, and the second part loss is 0.142 W.

The VM refrigerator, known as heat driven refrigerator, is one kind of closed-cycle regenerative refrigerator. There are some losses in VM refrigerator, but the losses in regenerator are the main loss when the refrigeration temperature is below 100 K. This paper present one method to calculate the pressure drop loss in the regenerator, which is one main part loss in the regenerator. The pressure drop loss in the regenerator will decrease the refrigeration capacity in two aspects. On the one hand, due to the friction pressure drop in the regenerator will be converted into heat that causes reduced the refrigeration capacity. On the other hand, the pressure drop in the regenerator will decrease the pressure ratio in cold end. From a practical standpoint, this calculation method was used for analysis one VM refrigerator proposed by Zhou in 1984. The results showed that the results by using this method are very close to the experimental results in three temperature points.