ABSTRACT
As is known to all, after a period of time of sustained work, the transmission of gear basically reaches the steady state, the temperature field can also be considered as steady state. But before this, the friction heat of tooth and also heat exchange with ambient environment are in non-equilibrium state, the temperature field is changeable along with time. Expressed in mathematical language, the temperature distribution can be expressed by temperature function, namely the temperature field is the function of time and space, suppose the temperature function is given by Equation 1:
T T x y z t( , , , ) (1)
1 INTRODUCTION
Due to friction and extrusion, the transmission gear accompanied by high speed and heavy load generally bears higher thermal load and thermal deformation, especially in the beginning stages of high speed gear, because of suddenly increased load, the gear bear huge instantaneous friction, the friction heat generated gather together in a short period of time, it cause that the temperature of friction surface rise quickly, the temperature gradient will change very rapidly, the internal of gear will produce the unsteady thermal stress, this kind of violent temperature gradient phenomenon usually called thermal shock[1-3]. Exorbitant temperature is the main reason for generating gluing and tear on the tooth surface, therefore, to study the thermal stress and thermal deformation distribution of gear caused by thermal shock, first of all the temperature field of gear under the thermal shock should be calculated, and then its stress field and deformation field determined, which provide the basis for the design of the gear strength.
