Research On Speed Experiment Method Of The Phase Locked Positioning Laser Flow Field In A Hydrodynamic Torque Converter

Represented by hydrodynamic torque converter of the hydrodynamic components has wide application in vehicle and machinery industry. In order to improve the work efficiency of hydrodynamic torque converter, strengthen the basic theory study of the flow field in the hydrodynamic torque converter is needed. Therefore, the study on the flow field test in the hydrodynamic torque converter is an effective measure to grasp the internal flow field state. Taking hydrodynamic torque converter pump wheel as an example, this paper has carried out non-contact three-dimensional velocity measurement experiments of flow field based on Laser Doppler Anemometry(LDA).Firstly, according to the geometrical characteristics of the flow channel and combined with the LDA system features, this paper puts forward a flow field velocity test scheme suitable for different positions of measurement, designing and manufacturing the hydrodynamic torque converter test box with transparent windows. With the designing and debugging of the laser path, the incident way of LDA laser applicable to different measuring positions in hydrodynamic torque converter is determined. Considering the test bench arrangement and the light path of laser probe, the accurate measured positions of each section in LDA coordinate system is determined, ensuring the accuracy of the test results.Secondly, according to the working state of the measured hydrodynamic torque converter, the LDA data acquisition and processing method is obtained to meet the high-speed rotating condition. The influence of the LDA system parameter for the data acquisition is analyzed, and the best LDA system sampling parameters is achieved.Besides, the reasons for error of the experimental measurement is analyzed. Through the noise signal analysis of wall and blade reflection, adopt the valid test data filtering method based on angle and velocity interval distribution. According to the characteristics of the measured signal, this paper studies and formulates the phase locking positioning data processing method, to analyze the speed data processing of each direction inside the hydrodynamic torque converter pump wheel. The coordinate transformation and three dimensional syntheses of the measured velocity data are made.Finally, taking pump wheel of D400 type hydrodynamic torque converter as test object, according to the velocity measurement design of the flow field inside the pump, LDA system is used to measure the velocity of pump entrance, middle and export surface at different speed ratio conditions. Tangential velocity, radial velocity and axial velocity are obtained for measured section position at different speed ratio conditions. Comparing the velocity trends at different speed ratios, taking the middle surface for example to compose the three-dimensional velocity vector chart, we test and verify that the hydrodynamic torque converter LDA testing scheme is feasible. Acquiring the internal flow parameter distribution, this paper grasps the features of the flow, to provide the theory basis for the subsequent design of the hydrodynamic torque converter.