Vapor cooling heat exchanger

Abstract

A vapor cooling heat exchanger is provided with: a partition wall for partitioning path for a fluid to be cooled through which a fluid to be cooled flows, and path for a refrigerant through which a refrigerant for cooling the fluid to be cooled flows; and fins which are disposed within path for a fluid to be cooled, and which is thermally connected to the partition wall. The fins constitute a first fin and a second fin, the local heat flux of which on the partition wall is smaller than the first fin. The first fin and the second fin are arranged on the basis of the relationship between the local heat flux on the partition wall and the heat flux limit of the refrigerant. As a consequence, the occurrence of local burn-out on the vapor cooling heat exchanger is suppressed.

1 . An vapor cooling heat exchanger comprising:
 a partition wall that separates a cooling target fluid passage, in which cooling target fluid flows, from a refrigerant passage, in which refrigerant for cooling the cooling target fluid flows; and   a fin that is arranged in the cooling target fluid passage and thermally connected to the partition wall, wherein   the fin includes a first fin and a second fin, the second fin decreasing a local heat flux of the partition wall by a greater degree than the first fin does, and   the first fin and the second fin are arranged based on the relationship between the local heat flux of the partition wall and the critical heat flux of the refrigerant.   
     
     
         2 . The vapor cooling heat exchanger according to  claim 1 , wherein the thickness of the second fin is greater than the thickness of the first fin. 
     
     
         3 . The vapor cooling heat exchanger according to  claim 1 , wherein the second fin is arranged in an upstream portion of the cooling target fluid passage in the flow direction of the cooling target fluid where the local heat flux of the partition wall increases. 
     
     
         4 . The vapor cooling heat exchanger according to  claim 1 , wherein the second fin is arranged in a zone of the cooling target fluid passage that corresponds to a downstream portion of the refrigerant passage in the flow direction of the refrigerant where the critical heat flux decreases. 
     
     
         5 . The vapor cooling heat exchanger according to  claim 1 , wherein
 the cooling target fluid passage and the refrigerant passage are arranged side by side such that the flow direction of the cooling target fluid and the flow direction of the refrigerant cross each other, and   the second fin is arranged in an upstream portion of the cooling target fluid passage in the flow direction of the cooling target fluid that is a zone in the cooling target fluid passage that corresponds to a downstream portion of the refrigerant passage in the flow direction of the refrigerant.   
     
     
         6 . The vapor cooling heat exchanger according to  claim 1 , wherein
 the second fin and the first fin have substantially equal surface areas.