We present a unified treatment for modeling Coulomb and viscous friction within multi-rigid body simulation using the principle of maximum dissipation. This principle is used to build two different methods—an event-driven impulse-based method and a time stepping method—for modeling contact. The same principle is used to effect joint friction in articulated mechanisms. Experiments show that the ...

This paper presents a nonlinear solver based on the Newton-Krylov methods, where the Newton equations are solved by Krylov-subspace type approaches. We focus on the solution of unsteady systems, in which the temporal terms are discretized by the backward Euler method using finite difference. To save computational cost, an adaptive time stepping is used to minimize the number of time steps. The ...

Abstract. We evaluate the fractional integral Iα[f ](t) = 1 Γ(α) ∫ t 0 (t− τ)α−1 f(τ) dτ , 0 < α < 1, at time steps t = Δt, 2Δt, . . . , NΔt by making use of the integral representation of the convolution kernel tα−1 = 1 Γ(1−α) ∫∞ 0 e −ξ t ξ−α dξ. We construct an efficient Q-point quadrature of this integral representation and use it as a part of a fast time stepping method. The new method has ...

A kind of integrated motor propulsor (IMP) which can be used in underwater propulsion is designed in this paper, and the rotor of its propelling motor employs the Halbach structure. This paper considers the characteristics of IMP, and coupling model of the motor is established. Time-stepping finite element method is used to analyze the field-circuit coupling problem, and research in the aspect ...

Solving an evolution problem in parallel is naturally undertaken by trying to parallelize the algorithm in space, and then still follow a time stepping method from the initial time t = 0 to the final time t = T . This is especially easy to do when an explicit time stepping method is used, because in that case the time step for each component is only based on past, known data, and the time stepp...

Simulations of many rigid bodies colliding with each other sometimes yield particularly interesting results if the objects differ significantly in size and are nonspherical. The most expensive part within such a simulation code is collision detection. We propose family novel multiscale detection algorithms that can be applied to triangulated explicit implicit time stepping methods. They well su...

This work presents, for the first time, a dual time stepping (DTS) approach to solve global system of equations that appears in hybridisable discontinuous Galerkin (HDG) formulation convection-diffusion problems. A proof existence and uniqueness steady state solution HDG problem with DTS is presented. The stability limit derived using von Neumann analysis, leading closed form expression critica...