天然气发动机混合器模块模型设计

Model design of mixer module for natural gas engine

为了提高国六天然气发动机空燃比控制精度,以天然气发动机混合器模块硬件结构为基础,设计天然气发动机混合器模块的模型,应用节流公式建立节气门和渐缩喷管模型、理想空气方程建立混合管段模型,并应用欧拉修正方法解决发动机瞬态运行过程中复杂非线性系统无法收敛问题;采集试验台架信号数据作为输入进行仿真与测试。结果表明混合器模型准确、有效,采用欧拉修正方法后,进气流量计算精度得到极大提高,未出现计算发散现象。

In order to improve the air-fuel ratio control accuracy of CHINAⅥnatural gas engine,based on the hardware structure of natural gas engine mixer module,the model of natural gas engine mixer module is developed,the throttle valve and tapered nozzle model are established by using throttling formula,the mixing pipe model is established by using ideal air equation,and the Euler correction method is used to solve the divergence problem that comes from the complex nonlinear system in the process of engine transient operation.The signal data of the test bench is collected as input for simulation and test.The test results show that the mixer model is accurate and effective.After using the Euler correction method,the accuracy of the intake flow calculated by the software model is greatly improved,and there is no calculation divergence.