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Using radial basis function-generated finite differences (RBF-FD) to solve heat transfer equilibrium problems in domains with interfaces

TLDR
In this article, a mesh-free, radial basis function-generated finite difference (RBF-FD)-based method for designing stencil weights that can be applied directly to data that crosses an interface is presented.
Abstract
When thermal diffusivity does not vary smoothly within a computational domain, standard numerical methods for solving heat equilibrium problems often converge to an inaccurate solution. In the present paper, we discuss a mesh-free, radial basis function-generated finite difference (RBF-FD)-based method for designing stencil weights that can be applied directly to data that crosses an interface. The approach produces a very accurate solution when thermal diffusivity varies smoothly on either side of an interface. It continues to produce high-quality results when a region between two interfaces is much smaller that the distance between adjacent discrete data nodes in the domain (as becomes the case for thin, nearly insulating layers). We give several test cases that demonstrate the method solving heat equilibrium problems to 4th-order accuracy in the presence of smoothly-curved interfaces.

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Citations
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An insight into RBF-FD approximations augmented with polynomials

TL;DR: The present study complements the previous results, providing an analytical insight into RBF-FD approximations augmented with polynomials, based on a closed-form expression for the interpolant, which reveals the mechanisms underlying these features, including the role of polynmials and RBFs in the interpolants, the approximation error, and the behavior of the cardinal functions near boundaries.
Journal ArticleDOI

Numerical approximation of the nonlinear time-fractional telegraph equation arising in neutron transport

TL;DR: The unconditional stability and convergence of the time-discretized formulation are demonstrated and confirmed numerically, and the numerical results highlight the accuracy and the validity of the method.
Journal ArticleDOI

Numerical approach for modeling fractal mobile/immobile transport model in porous and fractured media

TL;DR: In this paper, the radial basis function-generated finite difference (RBF-FD) is used to solve the fractal mobile-immobile transport model (FMTM) and the time fractional derivative of the FMTM is discretized via the shifted Grunwald-Letnikov formula with second-order accuracy.
Journal ArticleDOI

Numerical evaluation of the fractional Klein-Kramers model arising in molecular dynamics

TL;DR: A hybrid algorithm adopting the local radial basis functions based finite difference (LRBF–FD) for the numerical solution of the TFKKM, which describes the escape of a particle over a barrier and has a significant role in examining a variety of systems including slow (subdiffusion) dynamics.
Journal ArticleDOI

An efficient local meshless method for the equal width equation in fluid mechanics

TL;DR: In this article, an accurate and robust meshless approach for the numerical solution of the nonlinear equal width equation is proposed, which is based on the localized radial basis function-finite difference (RBF-FD) method.
References
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Journal ArticleDOI

Flow patterns around heart valves: A numerical method

TL;DR: In this paper, the Navier-Stokes equations on a rectangular domain are applied to the simulation of flow around the natural mitral valve of a human heart valve, where the boundary forces are of order h − 1, and because they are sensitive to small changes in boundary configuration, they tend to produce numerical instability.
Journal ArticleDOI

the immersed interface method for elliptic equations with discontinuous coefficients and singular sources

TL;DR: In this paper, the authors developed finite difference methods for elliptic equations of the form \[ abla \cdot (\beta (x)) + \kappa (x)u(x) = f(x)) in a region in one or two dimensions.
Journal ArticleDOI

Finite element methods and their convergence for elliptic and parabolic interface problems

TL;DR: In this article, the authors considered the finite element methods for solving second order elliptic and parabolic interface problems in two-dimensional convex polygonal domains and obtained the same optimal energy norm and energy norm error estimates as for regular problems when the interfaces are of arbitrary shape but are smooth.
Journal ArticleDOI

The finite element method for elliptic equations with discontinuous coefficients

TL;DR: The proposed approach on a model problem — the Dirichlet problem with an interface for Laplace equation with sufficient condition for the smoothnees can be determined, and the boundary of the domain and the interface will be assumed smooth enough.
Journal ArticleDOI

The parameter R2 in multiquadric interpolation

TL;DR: The multiquadric (MQ) method as discussed by the authors is an effective bivariate interpolant to three-dimensional data (xi, yi, zi), where the points are arbitrarily located in the plane and the accuracy of the MQ method is dependent on a user defined parameter R2, and most practitioners select R2 based upon the number of data points and the locations of the points in the planes.
Related Papers (5)
Frequently Asked Questions (10)
Q1. What are the contributions in this paper?

In the present paper, the authors discuss a mesh-free, radial basis function-generated finite difference ( RBF-FD ) -based method for designing stencil weights that can be applied directly to data that crosses an interface. The authors give several test cases that demonstrate the method solving heat equilibrium problems to 4th-order accuracy in the presence of smoothly-curved interfaces. 

Assumption of a standard polynomial basis on one side of an interface, along with explicit computation of the necessary changes to that basis that occur across the interface (through continuity matrix inversion), determines the piecewise polynomial functions that must be present in an expansion of temperature data near the interface. 

RBF-FDstencils that cross an interface or are close to the domain boundary contain 30 nodes and are supported by all polynomials up through 4th degree. 

To enforce continuity of temperature along a curved interface, after application of a given power k of the discrete form of the differential operator in (1), a local expansion for the interface shape itself (again, in terms of 'x ) can be inserted into entries for 'y . 

Although a value of 0.4 in the numerator of (31) has proven reliable in solving the test cases presented here, additional accuracy could possibly be gained by decreasing the numerator to a smaller constant (as long as the resulting RBF-FD weights produce an acceptably stable solution). 

In 1-D, support monomials were characterized across an interface by enforcing discrete forms of (6) and (7) for constant expansion coefficients (and constant term time derivatives) of temperature and heat flux. 

k k t k tu u D uy y n (27)Enforcing linear relationships between the expansion coefficients of as described in the last two paragraphs ensures that continuity of temperature and heat flux are upheld to ( )pO h accuracyat ' 0y for a mildly-curved interface that is locally very well-represented by a linearapproximation. 

Although the paper focuses on modification of the supplemental support polynomials to enforce interface continuity conditions, the authors also describe and implement a method for modifying the RBFs to help achieve the same goal. 

The radius from the center point (0.5,0.5) and heat diffusivity are defined as follows:0.52 2( 0.5) ( 0.5)r x y (37)1/1500 (1/ 3000)sin(2 )sin(2 ) 0.349 0.35 1 x y if r otherwise (38)There is also a third, circular Dirichlet boundary at 0.05 to simulate a cooling unit inside the insulating ring. 

The next 2-D test problem involves two mildly curved interfaces within a unit square that isperiodic in the -direction and closed at = 0 and = 1 (Figure 8).