Abstract
An electronically controlled accumulator type unit injector for two-stroke motorcycle engines was introduced . The injector has the simple structure, easily regulative injection timing and fewer requirements on the corresponding characteristics of a solenoid valve, etc. The structure design and experimental study of the injector have been carried out, and a mathematic model for the injection processes was established basing on the injectors operation principle and the simulation has also been completed. The calculation results coincided with the experimental results, which proves that the model is reasonable. Therefore, this mathematic model can be used to analyze the effects of the injector structural parameters and the rail pressure on the injection flow rate and the injection quantity in the optimization design of the injector and the coupled experimental evaluation with a specific two-stroke motorcycle engine.