A Simulation Study on the Effects of Swirl and Mass Flow Rate on Different Valve Lifts of IC Engine.

Abstract

The degree of engine strengthening is growing as CO2 emission rules become more rigorous. The airway throat sections of the intake and exhaust systems have a significant impact on the flow loss of the diesel engine under high-pressure circumstances. The proper distribution of the throat area of the intake and exhaust ports in the limited cylinder headspace is critical for increasing supercharged engine performance. The research object in this project was a large-bore, high-pressure ratio diesel engine.To begin, the three-dimensional (3D) flow simulation approach was used to disclose the effect law of different throat areas on engine intake and exhaust flow under steady-state circumstances, and a steady-flow test bench was developed to validate the simulation model and law. Second, using the 3D steady-state computation and test findings, a more accurate one-dimensional simulation model was built, and a joint optimization simulation platform based on the dynamic data link library was produced.Based on this, a mathematical expression of the multi-objective enhancement of airway throat size was formed using machine learning methods such as a genetic algorithm, the design domain and boundary conditions of variable parameters were clarified, and the collaborative optimization objective of integrated flow coefficient and flow loss is proposed to achieve fast and accurate optimization of intake and exhaust throat diameters.