Darcy's law

8 次查看（过去 30 天）

hasan damaj 2019-12-7

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/495382-darcy-s-law

回答： Hassan Abdullah Saleem 2020-10-12

clc
clear
% Laplace equation
% Define the length of the grid
L  = 5 ;
% Define the Width of the grid
B = 5 ;
nx = 4 ;
ny = 4 ;
dx = 100;
dy =  100;
h=zeros(nx,ny);
amax = 0;
% boundry conditions
h(1,:)  = [ 8.04 , 7.68 , 7.19 , 6.82 ];
h(nx,:) = [ 8.53 , 8.41 , 8.33 , 8.29 ];
h(:,1)  = [ 8.04 , 8.18 , 8.36 , 8.53 ];
h(:,ny) = [ 6.82 , 7.56 , 7.99 , 8.29 ];
while amax <= 0.01
	for j = 2 : nx-1
		for i = 2 : ny-1
			oldval = h(i,j);
			h(i,j) = ( h(i-1,j) + h(i+1,j) + h(i,j-1) + h(i,j+1)/4) ;
			e = abs(h(i,j)) - oldval;
			if e > amax
				amax = e;
			end
		end
	end
end
h

I NEED TO GET TO THE FOLLOWING RESULT

8.04 8.18 8.36 8.53

7.68 7.93 8.19 8.41

7.19 7.68 8.05 8.33

6.82 7.56 7.99 8.29

Can you suggest for me the correction and thank you :)

7 个评论
显示 5更早的评论隐藏 5更早的评论

hasan damaj 2019-12-11

the equation is correct sir..

hasan damaj 2019-12-11

the while condition is not working with me

请先登录，再进行评论。

请先登录，再回答此问题。

回答（3 个）

Image Analyst 2019-12-7

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/495382-darcy-s-law#answer_405301

在 MATLAB Online 中打开

You're setting up your boundary conditions incorrectly. You're overwriting the corners with different numbers. I think maybe you want this:

% Initialize boundary conditions:
h(1,:)  = [ 8.04 , 7.68 , 7.19 , 8.53];
h(end,:) = [6.82 , 7.56 , 7.99 , 8.29 ];
h(2:3,1)  = [7.68;7.19];
h(2:3,end)  = [8.41; 8.33];
h
% Here h should be
% 8.04          8.18    8.36    8.53
% 7.68           0       0      8.41
% 7.19           0       0      8.33
% 6.82          7.56    7.99    8.29