The multilevel fast multipole method (MLFMM) is an algorithm that has had great success in reducing the computational time required to find the solution to the Galerkin boundary integral form of the Helmholtz equation. We present a new formulation of the MLFMM using Fourier basis functions rather than spherical harmonics in order to accelerate and simplify the time-critical stages of the algori...

Transfer table is an essential stage between roughing and finishing rolling stands in a hot-strip rolling mill. High temperature and long time that strip is exposed to air at this stage cause a considerable heat loss that accounts for uneven temperature distribution, non-uniform surfaces, reduced product quality and increased production costs. Using thermal shields on the transfer table is cons...

Axially moving strips are frequently encountered in industry for various applications. On the one hand, accurate models of transverse displacements of strips are desired for plant design and safety or reliability reasons. On the other hand, the models may serve as a basis for model-based controller and observer design. For the latter also, the complexity of the models should be as low as possib...

In this paper we investigate the feasibility of using the ultra weak variational formulation (UWVF) to solve the timeharmonic 3D elastic wave propagation problem. The UWVF is a non-polynomial volume based method that uses plane waves as basis functions which reduces the computational burden. More general, the UWVF is a special form of the discontinuous Galerkin method. As a model problem we con...

A robust multilevel preconditioner based on the hybridizable discontinuous Galerkin method for the Helmholtz equation with high wave number is presented in this paper. There are two keys in our algorithm, one is how to choose a suitable intergrid transfer operator, and the other is using GMRES smoothing on coarse grids. The multilevel method is performed as a preconditioner in the outer GMRES i...

By the past two decades IPMCs have been intensively studied because of their special capabilities for actuation and sensing.This paper presents a theoretical physics based model for analyzing the behavior of IPMC sensors in fluid environments. The mechanical vibration of the IPMC strip is described by the classical Euler–Bernoulli beam theory. The model also takes in to account the physical pro...

A truly meshless Galerkin method is formulated in the present study, as a special case of the general Meshless Local Petrov-Galerkin (MLPG) “Mixed” approach. The Galerkin method is implemented as a truly meshless method, for solving elasto-static problems. In the present Galerkin method, the test function is chosen to be the same as the trial function, as a special case of the MLPG approach. Ho...

In this study, the momentum and energy equations of laminar flow of a non-Newtonian fluid are solved in an axisymmetric porous channel using the least square and Galerkin methods. The bottom plate is heated by an external hot gas, and a coolant fluid is injected into the channel from the upper plate. The arising nonlinear coupled partial differential equations are reduced to a set of coupled no...