Title: Numerical optimization of the piston bowl geometry and investigation of the key geometric parameters for the dual-mode dual-fuel (DMDF) concept under a wide load range
2022-01-0945
03/29/2022
- Event
- Content
- Focusing on the dual-mode dual-fuel (DMDF) combustion concept, a combined optimization of the piston bowl geometry with the fuel injection strategy was conducted at low, mid, and high loads. With the introduction of Sobol sampling method, the genetic algorithm (GA) was improved, which is superior in searching for the global optimal solutions. Meanwhile, a novel method was proposed for describing and parameterizing the piston bowl geometry. Moreover, by coupling KIVA-3V code with the enhanced GA, a total of 13 parameters including the piston bowl geometric parameters and the injection parameters were optimized with the objective of meeting Euro 6 regulations while improving the fuel efficiency. The optimal piston bowl shape coupled with the corresponding injection strategy was summarized and integrated at the various loads. The results show that the piston bowl geometry optimization can further improve the thermal efficiency over the test load range while the nitrogen oxides (NOx) and soot emissions are not deteriorated. The parameter open extent (OE) was defined for describing the type of the piston bowl shape. At low and mid loads, both the open and re-entrant type piston bowl can be equipped, while the high load only prefers the open type piston bowl for the DMDF mode. Meanwhile, the effects of the key geometric parameters were investigated in terms of organizing the in-cylinder flow and influencing the energy distribution. Furthermore, a correlation analysis was conducted to investigate the sensitivity of engine performance to the piston bowl geometric parameters and injection parameters over the whole load range.
- Citation
- Xu, G., Garcia, A., Jia, M., and Monsalve-Serrano, J., "Title: Numerical optimization of the piston bowl geometry and investigation of the key geometric parameters for the dual-mode dual-fuel (DMDF) concept under a wide load range," SAE Technical Paper 2022-01-0945, 2022, .