摘要 |
PROBLEM TO BE SOLVED: To improve the heat exchanging efficiency (cooling capacity) of an EGR gas cooler. SOLUTION: There is provided a guide seal wall 113 for preventing the flow of EGR gas, flowing into a core casing 143 (an exhaust passage 110) while detouring a gap 112 between tubes 110 with a high flow resistance. According to this method, much of the EGR gas, which has flowed into the core casing 143, can be prevented from flowing through a site (a gap 144 between cores) having no inner fins 111 and reduced in a heat exchanging efficiency. Accordingly, much of the EGR gas can be conducted to flow through the gap 112 between the tubes 110 having a high heat exchanging efficiency whereby the heat exchanging efficiency (the cooling performance) can be improved and the EGR gas can be cooled sufficiently. |