In order to better optimize the performance of electronically controlled injector

a simulation model of electronically controlled injector was established for a self-designed marine low-speed diesel engine by using AMESim software

and the accuracy of the model was verified by a dedicated test platform. Firstly

a quantitative analysis of the influence of various structural parameters on injector performance was carried out to screen out the structural parameters with greater influence. Then

with the purpose of improving the response rate of injectors needle valve

a numerical simulation method combining the orthogonal experiment and genetic algorithm was used to optimally match the structural parameters in order to obtain the weighting factor and the optimal combination of multi-target parameters for the different effects of key structural parameters on dynamic response characteristics of the needle valve. Results show that the diameter of fuel metering outlet is the structural parameter that has the greatest influence on response characteristics of a needle valve

followed by the diameter of the control piston and fuel metering inlet

while the volume of control chamber and the preload of needle valve spring have less influence. Compared with the original structural parameter scheme

after optimization by the orthogonal experiment

the needle rise time is shortened by 1.00ms coupled with the reduction of needle fall time by 1.40ms

and after optimization by the genetic algorithm

the needle response time is significantly improved

resulting in the reduction of needle rise time by 40.9%

and hence needle fall time by 29.1%.