Performance Study of EGR Cooler with Different Geometries & Comparison with Dimpled-Tube Type EGR Cooler using CFD

Exhaust gas recirculation (EGR) system is one of the post processing techniques and, it is widely used to meet emission standards. And it has been considered as the most effective means to reduce NOx emission from diesel engine. EGR cooler is a simple heat exchanger in which exhaust gas is cooled by coolant from engine itself. Our objective is to enhance the effectiveness of shell and tube type heat exchanger; So that exhaust gas recirculated will be cooled in this way combustion chamber temperature will be lowered & it reduces NOx emission. Therefore we create different models 1,2,3,4. Model-1 is simple shell and tube type and simulates its result on ANSYS by fluent 16.0 (Academic) solver. Then in model-2 we replaced simple tubes by internally rectangular finned type circular tube and get increased effectiveness of the same cooler. And in the model-3, we replace the plane tube in same model by spiral (rectangular cross-section) finned tube, and the Model-4, we replace simple tubes by Dimpled type tubes. Now compare all the four models by their effectiveness, and suggest to use most effective Model-4 among them. So the comparisons were made between shell & finned tube EGR cooler and shell & Dimpled tube type EGR cooler. And we predict the NOx emission for different EGR rate for our most effective Model i.e. Model-4 (Dimpled-tube).