Gear’s normal contact stiffness played an important role in the mechanical equipment. In this paper, the M-B fractal model is modified and the contact surface coefficient is put forward to set up the fractal model, considering the influence of friction, which could be used to calculate accurately the involute arc cylindrical gears’ normal contact stiffness based on the fractal theory and Hertz ...

The continuity, self-similarity, and self-affinity of a microscopic contact surface can be described by the Weierstrass–Mandelbrot (W–M) function in fractal theory. To address problems that existing normal load model does not take into account effect thermal stress is applicable to temperature variation joint giant magnetostrictive ultrasonic vibration systems, thermal–elastic–plastic establish...

The present investigation is to study the surface waves propagation with imperfect boundary between an isotropic elastic layer of finite thickness and a homogenous isotropic thermodiffusive elastic half- space with rotation in the context of Green-Lindsay (G-L model) theory. The secular equation for surface waves in compact form is derived after developing the mathematical model. The phase velo...

nonlinear hunting speeds of railway vehicles running on a tangent track are analytically obtained using hopf bifurcation theory in this paper. the railway vehicle model consists of nonlinear primary yaw dampers, nonlinear flange contact stiffness as well as the clearance between the wheel flange and rail tread. linear and nonlinear critical speeds are obtained using bogoliubov method. a compreh...

The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the...

Nonlinear hunting speeds of railway vehicles running on a tangent track are analytically obtained using Hopf bifurcation theory in this paper. The railway vehicle model consists of nonlinear primary yaw dampers, nonlinear flange contact stiffness as well as the clearance between the wheel flange and rail tread. Linear and nonlinear critical speeds are obtained using Bogoliubov method. A compreh...

the track stiffness experienced by a train will vary along the track. sometimes the stiffness variation may be very large within a short distance. one example is when an unsupported sleeper is hanging in the rail. track stiffness is then, locally at that sleeper, very low. at insulated joints the bending stiffness of the rail has a discontinuity implying a discontinuity also of the track stiffn...