Experimental comparison of air cooler designs in a heavy-duty diesel engine

Abstract

This study aims to increase the system efficiency by changing the design of heat exchangers used as intercoolers in locomotive engines. For this purpose, computational fluid dynamics analysis was performed for each of 12 different intercoolers. Since the position and outer dimensions of the intercooler on an en-gine cannot be changed, the new designs had the same dimensions as the outer dimensions of the existing intercooler. The designs made by changing the tube distances and shapes were compared with the existing intercooler in terms of temperature and pressure differences. As a result of the comparisons, the opti-mum design was determined and then a prototype was manufactured. The exist-ing intercooler and the newly designed intercooler were mounted on an engine and tested separately in the engine test unit. In the test program carried out at maximum speed in test engines, it was determined that the air cooler outlet tem-perature was 7 °C lower in the test engine to which the designed air cooler was connected, as compared to the test engine to which the existing air cooler was connected. The effective efficiency of the test engine to which Design 4 and De-sign 8 were connected were found as 31.62% and 33.74%, respectively.

Keywords

• Diesel Engine
• Intercooler
• Computational Fluid Dynamics Analysis

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