Optimization of magnetic circuit configuration for GDI injector based on MOSA algorithm

Abstract

GDI (Gasoline Direct injection) injector is one of the most important components in GDI engine, which requires high precision and dynamic response. The magnetic circuit configuration as the key part of GDI injector which decides the magnetic force, dynamic response, energy loss and temperature rising. All these factors directly or indirectly impact on the GDI injector comprehensive performance. The aim of this investigation is to optimize the magnetic circuit configuration and improve the comprehensive performance for GDI injector. The specific factors that influence the optimum operation of the GDI injector have been analyzed based on physical theories. MOSA (Multi Objective Simulated Annealing) algorithm is used to implement the multi-objective parameters optimization for the magnetic circuit configuration. To validate the optimization results the multi-physical fields coupling simulation based on Finite Element Method (FEM) is used, and the simulation results were validated by experiments. Compared the initial configuration to the optimized one, the comprehensive performances have great improvement after optimization. The results indicate that the methods can be used to GDI injector concept design and performances prediction. The essence of the GDI injector is an ultra-high-speed and giant force solenoid valve which required high frequency response,high power density and downsizing. Simultaneously, when GDI injector work- ing, multi-physical fields coupling effect on magnetic circuit cause the coupling mechanism is compli- cate to reveal. Since 1970s, with the rapid development of mathematics and computer sciences, a lot of new algorithm and new number simulation methods were utilized in industry. With the development of the electronic technology, electronic fuel injector have chance to be used in combustion engine. But now, the environmental regulations are much more stringent conventional design methodology cannot satisfy the requirements of combustion engine for high efficiencyand clean emission. Therefore, quicker dynamic response, higher power density and smaller size GDI injectors are necessary. That means new methods should be used to improve the comprehensive performance essentially.