Heat exchanger having means for reducing thermal stress

Abstract

The present invention relates to a heat exchanger having a means for reducing thermal stress. An object of the present invention is to provide an integrated heat exchanger configured to cool two types of heat exchange media having different temperatures, the heat exchanger having a means for reducing thermal stress and having a flow distribution structure in a tank in order to effectively disperse thermal stress caused by a temperature difference.

What is claimed is: 
     
         1 . A heat exchanger comprising:
 a pair of header tanks each having therein a fluid flow space defined by coupling a header and a tank, the pair of header tanks being spaced apart from each other at a predetermined distance and provided side by side; and   a plurality of tubes each having two opposite ends fixed to the header tank and configured to define flow paths for heat exchange media, the plurality of tubes being arranged in two rows in a forward/rearward direction,   wherein an internal space of the header tank is isolated and divided by a partition wall into front and rear heat exchange parts,   wherein the heat exchange media having different average temperatures flow in the front and rear heat exchange parts, respectively, and   wherein the partition wall has a thermal stress reducing means.   
     
     
         2 . The heat exchanger of  claim 1 , wherein the thermal stress reducing means is a flow distribution structure formed on the tank in a partition wall vicinity region adjacent to the partition wall that is a boundary line between the front and rear heat exchange parts, and the flow distribution structure is formed so that a flow rate of the heat exchange medium flowing in the internal space of the tube in the partition wall vicinity region is relatively lower than a flow rate of the heat exchange medium flowing in the internal space of the tube in the remaining region. 
     
     
         3 . The heat exchanger of  claim 2 , wherein the flow distribution structure is a flow rate adjustment baffle having one end fixed to an inner surface of the tank, and the other end disposed to be spaced apart from the internal space of the tube, the flow rate adjustment baffle being formed to reduce a flow rate of the heat exchange medium flowing in the internal space of the tube in the partition wall vicinity region. 
     
     
         4 . The heat exchanger of  claim 2 , wherein the flow distribution structure is a flow rate adjustment rib formed as a part of the tank protrudes to an inside of the header tank and an end of a protruding portion is disposed to be spaced apart from the internal space of the tube, and
 wherein the flow rate adjustment rib is formed to reduce a flow rate of the heat exchange medium flowing in the internal space of the tube in the partition wall vicinity region.   
     
     
         5 . The heat exchanger of  claim 2 , wherein the flow distribution structure is formed in one of the front and rear heat exchange parts where a temperature of the heat exchange medium is relatively high. 
     
     
         6 . The heat exchanger of  claim 5 , wherein a temperature of the heat exchange medium flowing in the rear heat exchange part is higher than a temperature of the heat exchange medium flowing in the front heat exchange part, and the heat exchanger the flow distribution structure is formed in the rear heat exchange part. 
     
     
         7 . The heat exchanger of  claim 2 , wherein the flow distribution structure is applied to all positions of the tubes. 
     
     
         8 . The heat exchanger of  claim 2 , wherein the flow distribution structure is formed to be spaced apart from only a position opposite to a position of the tube. 
     
     
         9 . The heat exchanger of  claim 2 , wherein the flow distribution structure is formed to correspond to a range of 10 to 20% of a width of the tube. 
     
     
         10 . The heat exchanger of  claim 1 , wherein the thermal stress reducing means is an air pocket formed in the form of an empty space in the partition wall. 
     
     
         11 . The heat exchanger of  claim 10 , wherein the air pocket extends in an extension direction of the partition wall. 
     
     
         12 . The heat exchanger of  claim 10 , wherein the air pocket is formed to be opened at an end directed toward the header. 
     
     
         13 . The heat exchanger of  claim 12 , wherein an opened portion of the air pocket is sealed by a gasket provided at a portion where the header and the tank are coupled. 
     
     
         14 . The heat exchanger of  claim 13 , wherein the gasket has a sealing protrusion protruding at a position corresponding to the opened portion of the air pocket. 
     
     
         15 . The heat exchanger of  claim 10 , wherein the heat exchanger has a leak check path formed in the tank and provided in the form of a flow path that allows the air pocket to communicate with the outside. 
     
     
         16 . The heat exchanger of  claim 1 , wherein the heat exchanger is a radiator in which a high-temperature coolant and a low-temperature coolant flow.