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Alexander Trounev
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It is not so difficult problem for FEM implementations. Please, see my post on https://mathematica.stackexchange.com/questions/214279/3d-elastic-waves-in-a-glass
![Figure 2][5] ![Figure 3][6] Since we have historical conjunction of Jupiter and Saturn I have prepared code with visualization planet Jupiter and Saturn with moons. First code also published [here][3]. Visualization of planet Jupiter: ...
In a current version of Mathematica 12.1 there is no special solver for integrodifferencial equations. [Here][1] we show solver with using Haar wavelets for dynamic system presented in a paper M.A. Khan, A. Atangana, Modeling the dynamics of...
I used the standard code to triangulate the mesh coord = CountryData["USA", "Polygon"][[1, 1, 1]]; bmr = BoundaryMeshRegion[coord, Line[Append[Range[Length[coord]], 1]]]; usatri = TriangulateMesh[bmr, MaxCellMeasure -> .1]; ...
There is a cylinder, and you use plane geometry. Equation `QE` is therefore erroneous. You do not use FEM at all. To use FEM, call `Needs["NDSolve`FEM`"]`, then read the tutorial on a page FEMDocumentation/guide/FiniteElementMethodGuide.
You changed the code and changed the question. My answer now looks out of place. Which question should I answer?
This can be used as a regular analytical solution, for example s = DSolve[{i[t] == Cr vc'[t], vc[t] == vco[t] (1 + m) - Lr i'[t], -(1 + m) i[t] - vco[t]/RL == Co vco'[t], vc[0] == Vcrmax, i[0] == 0, vco[0] == Vo}, {i, vc, ...
To answer this question, we can compare two methods for solving the heat equation: 1) the `"MethodOfLines"` in which boundary condition `Derivative[1, 0][u][5, t] == -h (u[5, t] - u1)` is used; and 2) FEM in which boundary condition `NeumannValue[-h...
There are many ways, I will show one of them. Let a random process be described by a function matRealizations = Table[Sin[RandomReal[-1, 1] t + RandomReal[]], {81}]; You can display them all together or selectively Show[Table[ ...
In this problem, it is necessary to coordinate the initial and boundary conditions, as well as use the solution method and increase the time interval to 200 for clarity. eq = { 2423750 Derivative[0, 1][T][x, t] - 50 Derivative[2,...