Advanced CFD-CHT and Coupled Combustion Analysis for Accurate Thermal Predictions in IC Engines

This research addresses thermal management challenges through an integrated computational investigation of combustion dynamics, coolant behavior, and structural heat transfer within a modern common-rail diesel engine. We developed and applied a novel synchronized CHT-CFD framework, significantly enhancing simulation accuracy while maintaining computational efficiency. Our approach first established a validated ۳D-CFD model of the complete combustion cycle using experimental data. Detailed thermal boundary conditions derived from this model were then applied to a high-fidelity ۳D-CHT analysis of the engine block's cooling jacket. A specialized two-way coupling technique effectively bridged the disparate time scales governing gas combustion, coolant flow, and solid heat conduction. Upon achieving thermal convergence, critical hotspots were precisely mapped. Analysis confirms that the thermal hotspots frequently develop at the inter-cylinder bridge-particularly in regions surrounding adjacent exhaust valves within the cylinder block. These hotspots are most pronounced near the exhaust ports in the cylinder head and along the exhaust valves themselves, where heat concentration is highest.

Keywords:

Conjugate heat transfer (CHT) , Iterative coupled CFD-FEA analysis , Full-cycle in-cylinder combustion simulation , Water jacket , Cylinder block and head