Abstract
In this study, degradation of heat transfer performance of multi-tube type EGR-cooler, which had spirally-grooved flow channel for exhaust gas, was evaluated by JE05 test mode. Cold start and hot start tests were conducted and deposition thickness after each test was measured. EGR-Cooler after cold start tests showed 10% degradation of thermal ratio and slight change of pressure loss. On the other hand, EGR-Cooler after hot start tests showed 37% degradation of thermal ratio and reduction of pressure loss. Deference of these results was assumed to be due to bulk density of deposit layer on heat transfer wall.
