A boundary element formulation for the solution of multiple moving boundary problems is presented and tested herein. A heat transfer problem involving heating of solid, melting of solid and vaporisation of liquid is considered. Numerical results show that the boundary element method is more suitable and more accurate than both finite difference and finite element methods for this kind of problems

Curved boundary treatments provide a means of improving the computational accuracy of the conventional stairshaped approximation used in lattice Boltzmann (LB) simulations. Furthermore, curved boundary treatments can be extended to the modeling of moving boundary problems simply by adding a momentum term to the bounced distribution functions at the solid surface. This study commences by investi...

The free-boundary compressible 1-D Euler equations with moving physical vacuum boundary are a system of hyperbolic conservation laws which are both characteristic and degenerate. The physical vacuum singularity (or rate-of-degeneracy) requires the sound speed c = γργ−1 to scale as the square-root of the distance to the vacuum boundary, and has attracted a great deal of attention in recent years...

We determine the asymptotic behavior of the system of Cahn-Hillard/Euler's equations that control the dynamics inside the thin boundary layer separating two inviscid, incompressible, and nearly immiscible fluids. This model was proposed recently in order to replace the classical moving boundary model of two immiscible fluids, separated by the interface with the surface tension. We formally veri...

The free-boundary compressible one-dimensional Euler equations with moving physical vacuum boundary are a system of hyperbolic conservation laws that are both characteristic and degenerate. The physical vacuum singularity (or rate of degeneracy) requires the sound speed c2 D 1 to scale as the square root of the distance to the vacuum boundary and has attracted a great deal of attention in recen...

Target tracking is a typical and important application of wireless sensor networks (WSNs). In the consideration of scalability and energy efficiency for target tracking in large scale WSNs, it has been employed as an effective solution by organizing the WSNs into clusters. However, tracking a moving target in cluster-based WSNs suffers the boundary problem when the target moves across or along ...

Numerical analysis of open channel ̄ows has largely con®ned to using ®xed boundaries in the numerical codes. Given the size of the problem domain, using ®xed boundaries often taxes the computational resources since the e€ect of the boundary is transferred on to its adjacent node in the ®rst few iterations. In this work, we explore the performance of a moving boundary in conjunction with central...

The magnetospheric boundary is always moving, making it difficult to establish its structure. This paper presents a novel method for tracking the motion of the boundary, based on in-situ observations of the plasma velocity and of one or more additional observables. This method allows the moving boundary to be followed for extended periods of time (up to several hours) and aptly deals with limit...

The edge and motion are the main features that human visual system (HVS) perceives intensively. This paper proposes an algorithm for the segmentation of the moving object with accurate boundary using color and motion focusing on the HVS perception in the general image sequence. The proposed algorithm is composed of three parts: color segmentation, motion analysis, and region refinement and merg...

Maxwell’s original slip boundary condition is widely misapplied in current rarefied gas flow calculations (e.g. in hypersonics, microfluidics). If its commonly-accepted form is applied in simulations of gas flows over curved or moving surfaces, crucial physics can be lost. We give examples of such cases. We also propose a new higher-order boundary condition which is based on Maxwell’s original ...