All Questions
31 questions with no upvoted or accepted answers
6
votes
0
answers
743
views
Are there well-known methods for navigating on kd-trees?
When you have a mesh, there are many well-known methods to navigate it, as for example using a half-edge data structure, that allows easy circulation around faces and vertices.
Are there similar ...
- 617
5
votes
1
answer
574
views
Finite volume a posteriori error estimation
I'm wondering what alternatives there are to a grid convergence study to judge solution accuracy for a given grid resolution when doing steady-state RANS simulations on an automatically generated ...
- 729
4
votes
0
answers
488
views
Why wall shear stress calculated from LBM directly and the one calculated based on velocity profile are so different in some cases?
First of all, I hope you accept my apologizes if my question seems off topic here. But, I asked this question in ParaView forum and after a week still I did not receive any response yet, so I'm ...
- 2,332
3
votes
0
answers
53
views
Datasets for inverse heat transfer problems
I was wondering if there is an available, real-life known inverse heat transfer problem dataset to benchmark oneselfs algorithm, as in MNIST for deep learning. Talking about... (well in this case I ...
- 191
3
votes
0
answers
108
views
Correct approach for thermal finite element simulation of layered assembly
I would like to optimise the heat transfer on a PCB. Several dies are on the top and cooling air is going through the fins in heat sink on the bottom. The assembly consists of several layers like ...
- 570
2
votes
0
answers
114
views
Efficient heat diffusion implementation with varying coefficients
I have the following heat diffusion equation:
\begin{alignat}{3}
\partial_t u(t, \vec{x}) &= g(\vec{x})\Delta u(t,\vec{x}), &\quad& \vec{x} \in\Omega, \, t\in(0,\infty],\\
\partial_n u(t,\...
- 2,892
2
votes
0
answers
113
views
Conceptual doubt regarding 2D conjugate heat transfer modelling (COMSOL and Mathemtica)
I have been dealing with some conceptual flaws in my understanding of modelling, which I will elaborate herein. I am modelling conjugate heat transfer of a reciprocating fluid, which flows with ...
- 41
2
votes
0
answers
80
views
Centered finite volume scheme for an advective term on an unstructured/irregular/non-uniform grid
Consider the continuity equation
$$\frac{\partial u}{\partial t} + \frac{\partial \Phi}{\partial x} = 0$$
$$\Phi = au + b\frac{\partial u}{\partial x}$$
Suppose I want to solve the above using ...
- 317
2
votes
0
answers
92
views
How to accelerate the computing of implicit finite difference method for heat conduction between two solids
Edit on May 3rd: I have found the problem. Because the difference of between $k_1$ and $k_2$ is huge, a very small time step need to be chosen so that the right green part can "feel" the ...
- 21
2
votes
0
answers
294
views
Rosenthal equation for multi track
Rosenthal's equation lets one calculate the temperature profile of a moving point heat source analytically for thin and thick plates. For simplicity I use the equation for thick plates defined as:
$$T-...
- 840
2
votes
0
answers
161
views
scalable parallel mesh/amr on unstructured grid
I am trying to code a scalable parallel AMR for unstructured grid. There seems to be three approaches for this
a) Store some global grid info on each processor and partition with parmetis (The ...
- 233
2
votes
0
answers
36
views
Choosing suitable polynomial degree based on information in advection stencil
I'm working on a finite volume advection scheme for unstructured meshes which uses a multidimensional polynomial weighted least squares fit for interpolating from cell centres onto faces.
In 2D, the ...
- 222
1
vote
1
answer
256
views
Coupled Partial Differential Equations
I'm trying to solve the following system of coupled differential equations, the two-temperature model for $e$ = electrons and $l$ = lattice.
$$
\rho_{e}C_{p,e}\frac{\partial T_{e}}{\partial t} = k_{e}\...
- 11
1
vote
0
answers
50
views
How can I apply a mixed boundary condition to a multi-material heat transfer problem using Crank-Nicolson?
I am working on a mixed material model for a melting material and need to enforce both a Dirichlet and Neumann type condition at the interface. Subject to an external surface heat flux at the top of ...
- 11
1
vote
0
answers
115
views
Accuracy of the Crank-Nicolson method for non-linear, inhomogeneous heat equation
I am currently coding a solution to the following PDE:
$\frac{\partial T }{\partial t} =\frac{\partial}{\partial \theta}(A(\theta ,\phi )\frac{\partial T }{\partial \theta}) +\frac{\partial }{\partial ...
- 11
1
vote
0
answers
64
views
Anisotropic lines identification algorithm
I am implementing an algorithm to identify the anisotropic lines in an unstructured mesh. This is done in the framework of an Agglomeration algorithm for Non-Structured multigrid applied to FV ...
- 410
1
vote
0
answers
43
views
Simultaneously partition all mesh elements (nodes, edges and cells) among processors
The numerical method that I'm implementing stores various fields in various elements of an unstructured triangular mesh. Data may be stored in cells, nodes and even edges of the mesh. For a parallel ...
- 165
1
vote
0
answers
194
views
Interpolation of a Concave Mesh
I would like to have an algorithm that interpolates the values attached to nodes in a concave mesh mesh.
To be me precise, assume we have a point cloud P (e.g. in 3 dimensions) and a list of edges E ...
- 119
1
vote
0
answers
61
views
Stress visualization for structured and unstrcutured mesh
I put together a FEM solver to do some structural analysis. At the moment I am trying to add stress visualization feature to my code. The post-processing is done with Paraview and the results with ...
- 600
1
vote
0
answers
456
views
Incorporating radiation boundary condition at the edge in finite difference
I am trying to solve the 2-d heat equation on a rectangle using finite difference method. I am confused as to how to incorporate non linear radiation boundary condition at the edge.
$-k\frac{\partial ...
- 19
1
vote
0
answers
68
views
Combining fluid flow solver based on lattice Boltzmann method with a mechanical deformation solver based on finite element method
I'm thinking to couple my fluid flow solver based on lattice Boltzmann method with a mechanical deformation solver based on finite element method to take account for solid deformation in my models. In ...
- 173
1
vote
0
answers
69
views
Efficient initial identification of solid or liquid domains for a block structured Cartesian grid generation system
INTRO
Within the last 5 days I was able to generate a block structured Cartesian grid
generation system with a combination of Fortran,C++ and Python.
I am running intersection tests of the ...
- 11
1
vote
0
answers
953
views
Methods and tools to solve the two-temperature model (TTM)
I would like to model heat diffusion at the gold / water interface after excitation of the metal surface by an ultrafast laser pulse (ca. 80 fs).
An appropriate model to start with would be the "two ...
- 21
1
vote
0
answers
212
views
BTCS-like method for heat conduction in unstructured triangular grid
I want to write a simple simulation for heat conduction in a unstructured triangular mesh.
I already made it work for a structured rectangular grid with the ADI method, but now I need more complex ...
- 23
0
votes
0
answers
45
views
Fastest way to check if mesh is structured?
What is the fastest and most efficient way of checking if a mesh is structured?
- 294
0
votes
0
answers
128
views
Heat Equation for fast source with FiPy
I'm trying to solve the following differential equation with FiPy, basically laser irradiation on a surface
$$
\rho_{s}C_{p,s}\frac{\partial T}{\partial t} = k_{s}\frac{\partial^{2}T}{\partial x^{2}} +...
- 11
0
votes
0
answers
38
views
Thermo Hydraulic Mechanical modeling of energy wall slab in Comsol multiphysics
I am currently working on a complex simulation project involving an energy wall slab, and I need assistance in accurately modeling and validating it using COMSOL Multiphysics. Here are the details of ...
0
votes
0
answers
50
views
Finding neighboring cells using Gmsh API
I am creating a simple mesh on a square domain, $[-5,5]\times[-5,5]$ using the following .geo file
...
- 183
0
votes
0
answers
68
views
Algebraic Grid Generation
I am new to the topic " Algebraic Grid Generation". I want to find a simple example where we solve the host equation, let us say the heat equation, numerically in the computational domain ...
0
votes
0
answers
77
views
deal.II and curved faces: how can I get the curved description
I'm not a deal.II expert, and while studying step-6 I was reading the documentation of the MappingQ1 class in the deal.II documentation. At some point in the description (https://www.dealii.org/...
- 435
0
votes
0
answers
86
views
How to calculate the interior value of triangular element in edge (vector) finite element?
I was using an edge (vector) finite element to solve electromagnetic diffusion (two-dimensional cases). The element that I used was a triangular element. I have got the result of the finite element in ...
- 9