You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
44 lines
1.3 KiB
44 lines
1.3 KiB
%--------------------------
|
|
% @Author: Jingqiao Hu
|
|
% @Date: 2021-02-22 13:20:56
|
|
% @LastEditTime: 2021-08-24 16:37:34
|
|
%--------------------------
|
|
function K = multi_stiffness_linear(dFdx, iK, jK, dx, global_u, global_l, lenout, D1, rho_cell)
|
|
|
|
eleNum = size(dFdx, 2);
|
|
jac = dx^2/4;
|
|
|
|
sK = zeros(lenout^2, eleNum);
|
|
|
|
for ele_ma = 1:eleNum
|
|
% tic
|
|
u = global_u{ele_ma};
|
|
l = global_l{ele_ma};
|
|
|
|
rho_e = rho_cell{ele_ma}(:); % m,1
|
|
tmp = speye(length(rho_e)) .* rho_e; % m,m
|
|
D = kron(tmp, D1);
|
|
|
|
% element stiffness
|
|
ke = 0;
|
|
for gp = 1:4
|
|
dFe = dFdx{gp, ele_ma}; % 4 * lenout * eleNum_mi
|
|
|
|
% dP1 = dPdF_fast_linear(u, l, dFe); % 4 * l * m
|
|
% dPT = permute(dP1, [2,1,3]); % l * 4 * m
|
|
% dP2 = reshape(dPT, lenout, []); % l * 4m
|
|
|
|
dF1 = permute(dFe, [2,1,3]); % l * 4 * eleNum_mi
|
|
dF2 = reshape(dF1, lenout, [])'; % 4m * l
|
|
|
|
ke_g = dF2' * D * dF2; % lenout * lenout
|
|
|
|
% ke_g = dP2 * dF2; % lenout * lenout
|
|
ke = ke + ke_g * jac;
|
|
end
|
|
% toc
|
|
sK(:, ele_ma) = ke(:);
|
|
end
|
|
K = sparse(iK, jK, sK);
|
|
K = (K + K')/2;
|
|
end
|