Page 572 - Design and Operation of Heat Exchangers and their Networks

Appendix 555

tHU_in = 180;
tHU_out = 180;
tCU_in = 20;
tCU_out = 40;
% equipment cost function: C_E = C_E_a + C_E_b ∗ A ^ C_E_c (A in m2)
C_E_a = 0.295260 ∗ 30800;
C_E_b = 0.295260 ∗ 750;
C_E_c = 0.81;
% utility cost functions: C_U_HU = C_U_H ∗ Q, C_U_CU = C_U_C ∗ Q
C_U_H = 110;
C_U_C = 10;
% heat transfer coefficients of H1, H2, C1, C2, HU1, HU2, CU1, CU2
alpha = [0.2, 0.2, 0.2, 0.2, 0.2, 0.2, 0.2, 0.2];

% schifted cold stream temperatures
tc_s_in = zeros(2, 1);
tc_s_out = zeros(2, 1);
for i=1:1:N_c
tc_s_in(i) = tc_in(i) + dtm;
tc_s_out(i) = tc_out(i) + dtm;
end

% temperature levels and sub-networks
t = zeros(100, 1);
for i=1:1:N_h
t(i) = th_in(i);
t(i + N_h) = th_out(i);
end
for i=1:1:N_c
t(i + 2 ∗ N_h) = tc_s_in(i);
t(i + 2 ∗ N_h + N_c) = tc_s_out(i);
end
N_SN = 2 ∗ (N_h + N_c);
for i=1:1: N_SN - 1
for j =i+1:1: N_SN
if (t(j) == t(i))
for k = j : 1 : N_SN - 1
t(k) = t(k + 1);
end
N_SN = N_SN - 1;