% ===========================================================================
% ==                                                                       ==
% == Course:     Chemical Plants II                                        ==
% == Title:      Cooling towers design                                     ==
% == Solution:   Countercurrent configuration                              ==
% == Author:     Prof. Alessandro Di Pretoro (SuPER,POLIMI)                ==
% ==             alessandro.dipretoro@polimi.it                            ==
% ==             https://super.chem.polimi.it/ing-alessandro-di-pretoro    ==
% == Date:       2021.10.05                                                ==
% ==                                                                       ==
%	=========================================================================

clc
close all
clear all

global hla hga Kua DHev A P B Gdry CpL Cu

% Physical Properties
Lin=18000;                                      % kg/h
Gin=13000;          							% kg/h
Tinwat=60;      								% °C
Toutwat=25;         							% °C
Tinair=22;      								% °C
P=760;      									% mmHg
Z=0.6;      									% relative humidity
Cu=0.26;        								% kcal/kg*K
CpL=1;          								% kcal/kg*K	
DHev=580;       								% kcal/kg
hga=5000;       								% kcal/m/h/K
hla=28000;              						% kcal/m/h/K

% Vapor Pressure Correlation
A=-49.705;                              		% Pev 1st coeff	mmHg vs °C
B=2.71;                                     	% Pev 2nd coeff mmHg vs °C