LAUSR

Abstract A mathematical model of the motorized spindle taking into account the influence of various fractal parameters is established. Weierstrass–Mandelbrot function (W–M function) shows that the fractal parameters are important that affect the contact characteristics. According to fractal theory, the thermal contact resistance (TCR) between contact surfaces is proposed, and the thermal contact conductance (TCC) verification experiment verifies its accuracy. The key nodes of the motorized spindle are divided and the heat-balance equations are solved. The accuracy of the thermal resistance network model is verified by the temperature–rise experiment. The results show that: the fractal dimension D and the fractal–amplitude coefficient G affect the complexity and contour height of the contact surface; the temperature of each component rises quickly and then remains stable; An increase in the D causes a decrease in the temperature of the nodes and an increase in the G causes an increase in the temperature of the nodes. The influence of fractal parameters on the thermal characteristics of the motorized spindle can not be neglected.