Page 518 - Design and Operation of Heat Exchangers and their Networks

Appendix 501

K2 = special_function_K(bB);
epsilon_h = 1 - nu_1 ∗ (nu_1 + aA ∗ bA ∗ K2 ^ 2);

% numerical
th(:, :) = 1;
tc(:, :) = 0;

ntuh = NTUh(1);
ntuc = NTUc(1);
[th, tc, thm, tcm] = crossflow_mixed_unmixed ...
(ntuh, ntuc, nx, ny, th, tc, A, T, D);
fprintf("thm_i =%f, tcm_i =%f\n", thm, tcm);
ntuh = NTUh(2);
ntuc = NTUc(2);
th(:, :) = thm;
for i=1:1:nx1
tc(i, 1) = tc(i, ny1);
end
[th, tc, thm, tcm] = crossflow_mixed_unmixed ...
(ntuh, ntuc, nx, ny, th, tc, A, T, D);

fprintf("thm =%f, tcm =%f, 1-thm =%f, e_h =%f\n", ...
thm, tcm, 1 - thm, epsilon_h);

case 25
% analytical
K2 = special_function_K(bB);
nu1 = special_function_nu(aA, bA);
nu_1 = special_function_nu_(aA, bA);
h1 = special_function_h(bA, aA, phi ∗ K2);
epsilon_h = (1 + h1 - nu1) ∗ nu_1;
% numerical
th(:, :) = 1;
tc(:, :) = 0;
ntuh = NTUh(1);
ntuc = NTUc(1);
[th, tc, thm, tcm] = crossflow_mixed_unmixed ...
(ntuh, ntuc, nx, ny, th, tc, A, T, D);
fprintf("thm_i =%f, tcm_i =%f\n", thm, tcm);