HEAT EXCHANGER

The present invention relates to a heat exchanger including a shell (10), through which a thermal fluid such as hydraulic oil passes, provided with a plurality of tubes (20) through which a thermal medium such as cooling water passes. The tubes (20) formed with disk-shaped transfer fins (21) are installed in a direction perpendicular to the flow direction of the thermal fluid. The transfer fins (21) of the adjacent tubes (20) are arranged at a triangular pattern to come into close contact with each other. Valleys (15) and ridges (16) are repeatedly formed on the inner surface of the shell (10), and the transfer fins (21) of the tube (20) come into close contact with the curved surface, thereby suppressing generation of ineffective flow bypassing the transfer fins (21) when the thermal fluid passes the shell (10). Also, since a pair of same assemblies is joined to each other to form the shell (10), the strong structure is achieved while the number of parts required when the heat exchanger is manufactured is decreased. Therefore, the heat transfer efficiency of the heat exchanger can be remarkably improved, and the steps of manufacturing the heat exchanger can be simplified. The pressure resistance and the air-tightness are improved, thereby simultaneously improving the quality of the heat exchanger and lowering the manufacturing costs.