Influence of the fin to baffle distance on temperature, stress distribution and fatigue life of a cooled Exhaust Gas Recirculation system

Abstract

Environmental concerns and the decline of Earth's natural resources are among the most prominent issues in today's society, leading to stringent policies regarding commercial vehicle emission products, such as nitrogen oxides (NOx) and carbon dioxide (CO2) emission levels. Aiming to reduce their environmental footprint, car manufacturers have chosen to integrate the Exhaust Gas recirculation (EGR) cooler technology into their vehicles decades ago, as this is a resourceful and effective technique for reducing NOx emissions. This technique is still applied in hybrid cars and is foreseen to be used in future moved vehicles, proving its contemporaneity, adequacy, and relevancy. Nevertheless, this technology requires that different factors be considered during the design phase, such as high gas temperatures, mechanical vibrations, and other loads, as these may affect overall performance and durability. Therefore, this study aims to assess the impact of varying the inner fińs length on the applied loads and how it may affect the EGR Cooler efficiency. To this end, Computer-Aided Engineering (CAE) tools using numerical methods, such as Finite Element Method (FEM) and Finite Volume Method (FVM), were applied. This investigation revealed that varying the inner fi length affects each of the applied loads differently, and increasing the length was shown to improve the heat transfer process of the EGR; however, it also increases the thermally induced stresses at the hottest region, diminishing the fatigue resistance of the component. The advantages and disadvantages of several configurations understudy were addressed in the work carried out.