Modeling and Simulating of Intake Pipe Fuel Film Dynamic Characteristic in Gasoline Engine Start Process

During the gasoline engine start process, both fuel quantity and fuel film parameter change, fuel film dynamics in intake pipe is not balance, which makes the fuel quantity from nozzle and fuel quantity into the cylinder not be equaled. In order to control the air fuel ratio accurately in gasoline engine start process, fuel film model of intake pipe need to be established accurately. The costumed fuel film model by Aquino is introduced in detail, and the characteristic of Aquino model used in gasoline engine start process is also analyzed. Based on Aquino fuel film model, a new dynamic fuel film model is presented, in which the change of intake parameters is consider. The air fuel ratio variable by presented model and by Aquino model is simulated by using SIMULINK in gasoline engine start condition, and the simulated result is compared with experiment data. The result shows that the intake pipe fuel film dynamic characteristic is accurately described by the presented model, and the accuracy by presented model is higher than that by Aquino model.