create a temperature distribution for a plane wall under transient heat conduction in matlab

To create a temperature distribution for a plane wall under transient heat conduction in Matlab, you can follow these steps:

  1. Define the geometry and initial conditions of the wall. For example, let's assume we have a plane wall of length L, width W, and thickness D, with a thermal conductivity k and a specific heat c. Let's also assume that the initial temperature of the wall is T0, and that the temperature on the left and right boundaries of the wall is maintained at T1 and T2, respectively.

  2. Discretize the wall into small elements or control volumes, along both the x and y directions. This can be achieved using the meshgrid function in Matlab.

  3. Apply the finite difference method to discretize the heat conduction equation in both time and space. This involves approximating the second-order spatial derivative of temperature with a central difference scheme, and the first-order time derivative with a backward difference scheme.

  4. Use a time-stepping algorithm, such as an explicit or implicit Euler method, to solve the resulting system of algebraic equations for the temperature distribution at each time step.

Here is some sample code that demonstrates how to implement the above steps for a simple case of a plane wall with constant thermal properties and boundary conditions:

main.m
% Define the geometry and initial conditions of the wall
L = 0.1;     % length of wall in meters
W = 0.1;     % width of wall in meters
D = 0.01;    % thickness of wall in meters
k = 10;      % thermal conductivity of wall in W/(m*K)
c = 1000;    % specific heat of wall in J/(kg*K)
rho = 1000;  % density of wall in kg/m^3
T0 = 20;     % initial temperature of wall in degC
T1 = 100;    % temperature on left boundary in degC
T2 = 20;     % temperature on right boundary in degC

% Discretize the wall into small elements
nx = 50;  % number of elements along x direction
ny = 50;  % number of elements along y direction
dx = L/nx;
dy = W/ny;
[x,y] = meshgrid(dx/2:dx:L-dx/2, dy/2:dy:W-dy/2);

% Define time parameters
tmax = 1000;       % maximum simulation time in seconds
dt = 0.1;          % time step size in seconds
nt = round(tmax/dt); % number of time steps

% Initialize temperature matrix
T = T0*ones(nx,ny);

% Apply finite difference method to solve heat conduction equation
for n = 1:nt
    % Compute spatial derivatives using central difference scheme
    Tx = (T(2:end,:)-T(1:end-1,:))/dx;  % dT/dx
    Ty = (T(:,2:end)-T(:,1:end-1))/dy;  % dT/dy
    Txx = (T(3:end,:)-2*T(2:end-1,:)+T(1:end-2,:))/dx^2;  % d^2T/dx^2
    Tyy = (T(:,3:end)-2*T(:,2:end-1)+T(:,1:end-2))/dy^2;  % d^2T/dy^2
    
    % Compute temperature at next time step using backward Euler method
    Tnew = T + dt*k/(rho*c)*(Txx + Tyy);
    Tnew(:,1) = T1;   % apply left boundary condition
    Tnew(:,end) = T2; % apply right boundary condition
    T = Tnew;
end

% Plot the temperature distribution at final time step
surf(x,y,T')
xlabel('x (m)')
ylabel('y (m)')
zlabel('Temperature (degC)')
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This code will generate a 3D plot showing the temperature distribution in the wall at the final time step of the simulation. Note that this is a simplified example, and more complex scenarios may require additional modifications to the code.

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