Appendix 2
EES Software Coding
EES code is written and used for modeling simulation and optimization of polygeneration hybrid solar and biomass system for power, cooling, and desalination.
Efficiency_PTCfirstlaw = = efficiency_0-(a *((Tm-Ta)/DNI))-(b*((Tm-Ta)∧2/DNI)) “Parabolic trough collector field”
efficiency_0 = 0.67 “The optical efficiency has been taken as per 1 MW Solar Thermal Power Plant installed at NISE”
a = 0.1 “First order coefficient of the collector efficiency”
b = 0.001 “Second order coefficient of the collector efficiency”
DNI = 450 “DNI”
Ta = 35 “Ambient temperature”
m_oil = 25
Area = 18000 “Area of parabolic trough collector solar field”
C_p = 2600 “Specific heat of therminol VP-1 J/kg.K”
Q_Solar = (DNI/1000)*Area “Heat from Solar”
Q_PTC = (efficiency_PTCfirstlaw*DNI*Area)/1000
Delta_T = (Q_PTC*1000)/(m_oil*C_p) “Generation of heat energy from PTC field”
T_y = 240 “Oil temperature inlet to the PTC field”
T_x = T_y + Delta_T “Oil gets heated from PTC field and inlet to heat exchanger”
Tm = (T_x + T_y)/2 “Mean Temperature”
“State Point -1”
P_1 = 10
T_1 = T_sat(R718, P = P_1)
h_1 = Enthalpy(R718, P = P_1,x = x_1)
x_1 = 0
s_1 = Entropy(R718, P = P_1,x = x_1)
“State Point -2”
s_1 = s_2 P_2 = 500
T_2 = Temperature(R718, P = P_2,s = s_2)
h_2 = Enthalpy(R718, T = T_2,P = P_2) P_2 = P_3
“State Point -5”
P_5 = 6000
T_5 = 500
h_5 = ENTHALPY(R718, T = T_5,P = P_5)
s_5 = ENTROPY(R718, T = T_5,P = P_5)
“State Point -6”
P_6 = 597 s_5 = s_6
x_6 = Quality(R718, P = P_6,s ...