The inspections of temperature field and thermal stress field of wet clutch always behave as one of the key points of improving the structure of clutch friction discs.Currently,solving the response time of temperature measurement system and the layout scheme of temperature measuring points has become the key issues.Based on the recent theory studies of friction surface physical fields at home and abroad,this dissertation makes a deep research on the key technical issues.A real-time and accurate design method for measuring temperature field and thermal stress field of wet clutch friction surface is presented.According to the finite element simulation of friction surface temperature and thennal stress field under the actual operating conditions,the temperature sensor disposal method has been studied as the basis for the design of measurement system.Depend on the physical field distribution characteristics,the positions of hot spots and the regions where thermal stress is relatively large are obtained.A method of describing the whole temperature field distribution of the friction surface with less measure points has been proposed.Suitable thermocouple and amplifier chip have been selected on the basis of the principal of high temperature measurement speed.Furthermore,the external interferences are dealt by the combination of circuit shielding technology and external shielding technology.In addition,this dissertation has studied the least square fitting method for removing outliers and wavelet analysis for filtering the signal.Testify the accuracy and real-time of the system through the dynamic and static calibration of thermocouple.Finally the validity of the designed measure-ment system is tested by the test which simulates the real situation. |