Coolant Velocity Correlations in an IC Engine Coolant Jacket 2002-01-1203

Understanding the coolant behavior in the coolant jacket of an IC engine is critical to designing IC engines. Proper coolant jacket design is mandatory not only to ensure the durability of the engine, but also to improve its thermal efficiency over a wide range of engine speeds. To this end, coolant flow analysis assists in the metal temperature predictions as it provides flow information that can be used to derive the appropriate coolant-side heat transfer conditions. The coolant flow inside the engine, however, is very complex, primarily due to the complicated geometry of the coolant jackets. Contemporary practice of studying the coolant jackets is with the help of commercially available Computational Fluid Dynamics (CFD) codes. Though it is fairly common in automotive industry to perform CFD analysis on the coolant jackets, there has been very limited experimental work conducted to study the validity of using CFD for such purposes. The present work aims at bridging this gap. Through CFD analysis, and experimental measurements in the coolant jacket of an experimental V8 engine, it was found that, though the mean velocities correlate reasonably well with CFD predictions, the free stream turbulence intensities are well under predicted. Further analysis of the implications of these findings need to be performed to better utilize CFD for accurate metal temperature predictions.