Page 511 - Design and Operation of Heat Exchangers and their Networks

494 Appendix

% numerical
t1(:, :, :) = 1;
t2(:, :, :) = 0;
smax = 100;
n=0;
while (abs(smax) > eps && n < 100)
smax = 0;
ntuh = NTUh(1);
ntuc = NTUc(1);
th(:, :) = t1(1, :, :);
tc(:, :) = t2(1, :, :);

[th, tc, , ] = crossflow_unmixed_unmixed ...
(ntuh, ntuc, nx, ny, th, tc);
for i=1 :1:nx1
for j=1:1:ny1
s = th(i, j) - t1(1, i, j);
if (abs(s) > abs(smax))
smax = s;
end
t1(1, i, j) = t1(1, i, j) + e ∗ s;
s = tc(i, j) - t2(1, i, j);
if (abs(s) > abs(smax))
smax = s;
end
t2(1, i, j) = t2(1, i, j) + e ∗ s;
end
end
for j=1 :1:ny1
t1(2, 1, j) = t1(1, nx1, ny1 -j+1);
end

ntuh = NTUh(2);
ntuc = NTUc(2);
th(:, :) = t1(2, :, :);
tc(:, :) = t2(2, :, :);

tc(:, 1) = t2(2, :, 1);
[th, tc, thm, tcm] = crossflow_unmixed_unmixed ...
(ntuh, ntuc, nx, ny, th, tc);