| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve a problem of degradation in heat transmission efficiency caused by mineral oil property insoluble in ammonia refrigerant, in a dry type evaporator using the ammonia refrigerant and the lubricating oil insoluble in the ammonia refrigerant. <P>SOLUTION: Inside each of heat transmission tubes 70 of a multitubular horizontal shell-and-tube-type dry-type-evaporator 20, a wire coil 72 is prepared for a whole length of the heat transmission tube 70. The wire coil 72 is made by forming a small-diameter steel wire in a helical shape. The ammonia refrigerant is separated into gas and liquid to be a two-phase layer flow ammonia refrigerant. The wire coil 72 generates a swirl flow s in the two-phase layer flow ammonia refrigerant flowing in the heat transmission pipe 70, and a side face and a top face of the heat transmission tube 70 are wetted with the ammonia liquid, so that heat transmission performance between the ammonia liquid and an NaCl brine is improved. Therefore, a COP (coefficient of performance) of a refrigerating device 10 is improved. <P>COPYRIGHT: (C)2013,JPO&INPIT |
