37 lines
No EOL
863 B
Matlab
37 lines
No EOL
863 B
Matlab
function [K, F] = ApplyRobinBC_mult_rot(model, K, F, alpha, u_out)
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mesh = model.Mesh;
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nodes = mesh.Nodes;
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robinEdges = [4, 5, 6, 11];
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for eID = robinEdges
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edgeNodes = findNodes(mesh,'region','Edge',eID);
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for k = 1:length(edgeNodes)-1
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i = edgeNodes(k);
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j = edgeNodes(k+1);
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xi = nodes(:,i);
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xj = nodes(:,j);
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% Edge length
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L = norm(xi - xj);
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% Axisymmetric radius at midpoint
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rbar = 0.5 * (xi(1) + xj(1));
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% Skip axis (safety, should not occur here)
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if rbar == 0
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continue;
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end
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% Robin element matrices (linear edge)
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Ke = rbar * alpha * L / 6 * [2 1; 1 2];
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Fe = rbar * alpha * u_out * L / 2 * [1; 1];
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% Assemble
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K([i j],[i j]) = K([i j],[i j]) + Ke;
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F([i j]) = F([i j]) + Fe;
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end
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end
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end |