Cooling structure, heatsink and cooling method of heat generator

Abstract

A cooling structure includes a heat dissipation structure having a heat generator and a heatsink that is adhered through an insulating adhesive layer to at least a surface of the heat generator that faces a cooling fluid and made of a metal foil having the flexibility. A fluid flow path is disposed outside of the heat dissipation structure so that the cooling fluid flowing inside thereof and the heatsink may directly come into contact. Further, a fine recess is disposed on a surface of the heatsink that directly comes into contact with the cooling fluid.

1 . A heatsink directly coming into contact with a cooling fluid flowing in a fluid path, and exchanging heat with the cooling fluid, and
 a fine recess disposed on a heat transfer surface of the heatsink in contact with the cooling fluid, wherein the fine recess extends along a direction intersecting with a flow direction of the cooling fluid,   wherein viewed in a cross section of the fine recess along the flow direction of the cooling fluid, the fine recess is asymmetric.   
     
     
         2 . The heatsink according to  claim 1 ,
 wherein a first angle between the heat transfer surface of the heatsink and an inner wall surface of the fine recess at an upstream side in the flow direction differs from a second angle between the heat transfer surface of the heatsink and an inner wall surface of the fine recess at a downstream side in the flow direction, and   wherein the larger of the first angle and the second angle is larger than 30 degrees.   
     
     
         3 . The heatsink according to  claim 1 ,
 wherein a shape of the fine recess in a depth direction of the fine recess, in the cross section along the flow direction of the cooling fluid, is substantially an anisosceles trapezoid or substantially an inequilateral triangle.   
     
     
         4 . The heatsink according to  claim 1 ,
 wherein a shape of the fine recess in the cross section along the flow direction of the cooling fluid is identical to a shape of the fine recess in a cross section along a direction intersecting with the flow direction of the cooling fluid.   
     
     
         5 . The heatsink according to  claim 1 ,
 wherein the fine recess extends in a direction close to the flow direction of the cooling fluid.   
     
     
         6 . The heatsink according to  claim 1 ,
 further comprising a bypass groove disposed along the flow direction of the cooling fluid and connected with the fine recess.   
     
     
         7 . The heatsink according to  claim 1 ,
 wherein a substantial center portion of the surface of the heatsink provided with the fine recess faces a cooling fluid intake port, from where the cooling fluid flows in the fluid flow path.   
     
     
         8 . A heatsink directly coming into contact with a cooling fluid flowing a fluid path and exchanging heat with the cooling fluid,
 wherein a fin is disposed on a heat transfer surface of the heatsink,   wherein a fine recess extending along a direction intersecting with a flow direction of the cooling fluid is disposed on a surface of the fin, and   wherein, when viewed in a cross section of the fine recess along the flow direction of the cooling fluid, the fine recess is asymmetric.   
     
     
         9 . The heatsink according to  claim 8 ,
 wherein a first angle between the surface of the fin and an inner wall surface of the fine recess at an upstream side in the flow direction differs from a second angle between the surface of the fin and an inner wall surface of the fine recess at a downstream side in the flow direction, and   wherein the larger of the first angle and the second angle is larger than 30 degrees.