Cooling Loss Improvement of Diesel Combustion Using Highly Dispersed Sprays with Restricted In-cylinder Swirl and Squish Flows

To improve cooling loss of new clean diesel combustion with highly dispersed sprays with restricted in-cylinder flow, heat flux toward the combustion chamber was simulated. Moreover, to validate results of the simulation and identify the main locations where cooling loss occurred, local heat flux toward the combustion chamber was measured by thin film thermocouples. Cooling loss was found to occur at the sidewall of the piston cavity and the squish region of the cylinder head. This cooling loss was caused by convective heat transfer with reversed squish flow. A new combustion chamber restraining reversed squish flow was designed and fuel consumption was improved.