Abstract:Currently the theoretical filtration ratio is usually adopted when studying the vehicle hydraulic system filters, but in actual conditions,the filtration ratio of the filter is far less than the theoretical value.Aimed at the problem of how to determine the actual filtration ratio of hydraulic system filters in different use conditions,according to the working principle of filters,repetitive filtration ratio and repetitive contamination rate were defined in concepts,and the filter model with dynamic filtration ratio was established.Simulation of the model of dynamic filtration ratio was done by using MATLAB/Simulink,and influence of repetitive filtration ratio and repetitive contamination rate on dynamic filtration ratio was analyzed.The results show that the dynamic filtration ratio of filter is always in fluctuation state along with change of working condition of the system.Along with increasing of repetitive filtration ratio and repetitive contamination rate,dynamic filtration ratio is decreased rapidly.Change of dynamic filtration ratio was got by building experimental platform of filter with different flow rate,pressure and temperature of the system.The study result shows the model of dynamic filtration ratio meets the actual working condition better,and could be used for control the contamination of hydraulic system.