According to the motion relationship oftransmission system and the advanced parameter modeling method of gear, bearing and other key components introduced above, the rigid body dynamics simulation analysis model of gearbox transmission system with tooth surface pitting characteristics is established. The Runge Kutta numerical method with adaptive step size is used for numerical analysis. In order to capture the analysis result data of the system as much as possible, the data sampling frequency is set to 10000hz to ensure the integrity of the system data results. Through simulation analysis and calculation, a series of response output results between gear systems can be obtained. Because there are many data output response parameters, only some dynamic response characteristics (such as time-varying meshing stiffness, DTE, meshing force, etc.) are selected for research and analysis, and the influence of pitting characteristics on system dynamics is directly or indirectly reflected from the analysis results.
According to the time-domain signal response output after system simulation, the response characteristics of time-varying meshing stiffness of gears between gear pairs are analyzed firstly. The curve variation characteristics of time-varying meshing stiffness without pitting and with pitting are shown in the figure.
The time-varying meshing stiffness curve of the gear within 0.2S is drawn in figure (a). It can be seen that the time-varying meshing stiffness of the gear is reduced due to the effect of the pitting feature of the tooth surface, and the pitting setting area includes both double meshing area and single meshing area, so the meshing stiffness of the double meshing area and single meshing area decreases in the pitting area This is a phenomenon.
In order to further quantify the effect of stiffness reduction, select three or four tooth meshing cycles to draw the local enlarged diagram of time-varying meshing stiffness curve, as shown in figure (b). The statistical index G2 and G3 are used for quantitative analysis of stiffness reduction. In the double meshing area, because the statistical index g is difficult to capture, the maximum difference of stiffness at a certain time is used to describe. The results show that the maximum stiffness difference of the meshing zone is 2.54 × 108 n / m, and the stiffness reduction percentage is 32.3% compared with the non pitting stiffness. For the statistical index G3, the average stiffness without pitting is 79.1 million n / m, the average stiffness with pitting is 67.8 million n / M, and the average stiffness reduction percentage is 14.2% . Similarly, in the single mesh zone, the statistical index G2 with pitting stiffness is 150 million n / m, and the maximum stiffness reduction percentage is 65.3%; for the statistical index G3, the average stiffness without pitting is 43.7 million n / m, the average stiffness with pitting is 27.3 million n / m, and the average stiffness reduction percentage is 37.5%. From the stiffness reduction effect of double meshing area and single meshing area, the pitting action area has obvious effect on the meshing stiffness reduction of single meshing area.