| The environmental degradation is becoming more and more serious owning to theenergy drying up and fossil fuel burning, so the research of solar energy is becoming ahot spot of the renewable energy utilization. However for the characteristics of sunmoving, a drive system for real-time tracking must be taken to achieve the mosteffective collection of solar energy. Heliostat is one of the most effective devices forcollecting solar energy. As main transmission parts of heliostat, planetary geartransmission system has high reliability, high torque, high power density and smallvolume etc. Because of high friction heat generating, gear teeth bear high heat load andhigh temperatures would not only cause thermal deformation but also affect lubricationeffect severely and then transmission performance, that will have negativeconsequences for precise tracking. Therefore, the analysis of reducer planetary geartemperature field has the vital significance.Based on the principles of gear meshing, Hertz contact analysis, tribology and heattransfer theory, by means of theoretical analysis, finite element simulation andexperimental verification, the bulk temperature field for annular gear of heliostatplanetary reducer is studied.The major content is as follows:â‘ The structure of heliostat planetary gear reducer were analyzed, thethree-dimensional entity model of planetary gear reducer was established and the finiteelement object was simplified, the applications of classic heat transfer theory andthermal analysis on the planetary gear thermal steady state performance wereinvestigated.â‘¡The change law of the relative sliding speed and tooth surface frictioncoefficient between the planet gear and annular gear were studied, the gear tooth surfacecontact stress and frictional heat flux at different engaging positions and the heattransfer coefficient of gear end face and tooth surface were calculated precisely.â‘¢Three-dimensional finite element models of gear tooth were established andANSYS thermal analysis methods and steps of the planetary gear was discussed, takinginto account the input rotating speed, torque, the external environment factorssynthetically. Thermal analysis was carried out on the planetary gear, and the steadytemperature field was obtained, the various factors affecting gear temperature field were systemic discussed.â‘£In order to verify the conclusions of the previous chapters, related temperaturerise experiments of three-step series2K-H planetary gear reducer were carried out. Theexperimental test equipment and test methods were described, and the experimentaltesting process and related notes were described detailedly, In addition, the experimentaldata obtained were analysed and some methods which improved thermal properties ofplanetary gear reducer were proposed. |
