Based on the dynamic contact finite element method

the process of the gears meshing is simulated.As a result

the time-varying mesh stiffness is obtained.Then

the multi-body dynamics model of a certain engine is developed;using this model the dynamic output

which is the external excitation of the vehicle gear and shaft system

is calculated.A new method

by using the temperature variation to control the stiffness of the elements to agree with the time dependant mesh stiffness

is put forward

and the expected result is get.It can be concluded that the change in system natural frequency resulting from the time average of the mesh stiffness is slightly affecting the dynamic response.To some extent

the time average of the mesh stiffness can be used to take place of the time variable one.