The spectral properties of curved quantum wires with Dirichlet boundary condition were widely investigated (e.g. [1], [2], [3]). It was shown that any small curvature of the tube in dimensions 2 and 3 produces at least one positive eigenvalue below the essential spectrum threshold. The problem of the existence of such eigenvalues in the straight quantum waveguides with a combination of Dirichle...

We study the motion of a grain boundary that separates two sets of mutually perpendicular rolls in Rayleigh-Bénard convection above onset. The problem is treated either analytically from the corresponding amplitude equations, or numerically by solving the Swift-Hohenberg equation. We find that if the rolls are curved by a slow transversal modulation, a net translation of the boundary follows. W...

in this paper, two dimensional natural convection heat transfer in non-square cavities such as triangle, trapezoid, quadrant-circle and semi-circular are investigated via lattice boltzmann method. the prandtl number is taken as 0.71 that corresponds to that of air. the results show that, when the flow pattern consists of two rotating cell, there is a extremum point in the variations of the loca...

We prove a regularity result for the anisotropic elasticity equation Pu := div ` C · ∇u) = f , with mixed (displacement and traction) boundary conditions Lk on a curved polyhedral domain Ω ⊂ R 3 in weighted Sobolev spaces Ka (Ω), for which the weight given by the distance to the set of edges. In particular, we show that there is no loss of Ka –regularity. Our curved polyhedral domains are allow...

We study boundary effects in a linear wave equation with Dirichlet type conditions in a weakly curved pipe. The coordinates in our pipe are prescribed by a given small curvature with finite range, while the pipe’s cross section being circular. Based on the straight pipe case a perturbative analysis by which the boundary value conditions are exactly satisfied is employed. As such an analysis we ...

Heat transfer measurements are made to investigate the e ects of concave surface curvature on a high-stagnation enthalpy boundary layer in a Mach 5.1 ow. Experiments are carried out using two curved models with 16 and 25 degree turning angles, and baseline planar models ( at plate and linear ramp) for comparative study. Streamwise and spanwise cross-sections are obtained. Signi cant destabiliza...

Subjects judged whether two marks placed at different positions along a curved contour were physically the same. When targets were separated by a concave curvature extremum--corresponding to a part-boundary--decision latencies were longer than when they straddled an equally curved convex extremum, demonstrating a "single-part superiority effect". This difference increased with both stimulus dur...

A high order accurate discontinuous galerkin method based curvedelement implementation in OpenFOAM is presented in this work. The degree of freedom points on origin straight side mesh are mapped to curvilinear edges by finding nearest points on boundary. Then the deformation are transported to the inner points by blended method. Based on the run-time dynamic code of OpenFOAM, we design a conven...