How to give initial guess and initial condition for a nonlinear - time dependent PDE problem (transient non-linear heat equation) in pde tool box?

4 Ansichten (letzte 30 Tage)
I have (transient non-linear heat equation) i.e , k = 0.7 + 0.003*T, tlist = linespace(0,0.5,20); therefore my pde coefficients wills be d = 1, m = a = 0, c = k, f = 1; since c coefficent is non linear (dependent on T, temperature), My Intial Boundary condition is 3 and initial guess is 5. But i see command IC and initial guess is same. i.e setInitialConditions(model,u0); So how do i differentiate them?
This is how my code goes
clear,clc,close all;
model = createpde();
%% Geometry
R1 = [3;4;-1;1;1;-1;-1;-1;1;1];
g = decsg(R1);
heatmodel_geom = geometryFromEdges(model,g);
%% Mesh
msh = generateMesh(model,'GeometricOrder','linear');
[P,E,T] = meshToPet( msh );
%% Specify Coefficients
c = @(~,state) 0.7+0.003*state.u; % nonlinear coefficient
%% Spacial BC
applyBoundaryCondition(model,'dirichlet','edge',[1 2 3 4],'u',0);
%% Initial guess and initial condition
setInitialConditions(model,3); % Initial condition
setInitialConditions(model,5); % Initial guess to solve non linear pde.... BUT DO I DIFFERENTIATE BOTH THIS COMMANDS TO ITS RESPECTIVE JOBS

Akzeptierte Antwort

Ravi Kumar
Ravi Kumar am 4 Mär. 2021
For nonlinear elliptic problem, inputs in setInitialCcnditions is the initial guess for the nonlinear solver. For time-dependent problems initial condiions and initial gues are one and the same.

Weitere Antworten (0)

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by