![11/18/16 12:55 PM C:UsersAlexi...MATLAB_Final_Project.m 1 of 2
%Final Project
%Ratio Funtion File (Mixing_Ratio.m) for Delta_q Funtion File
function [w] = Mixing_Ratio(T_a, p_a)
%Mixing Ratio calculates the ratio of the mass of water vapor to the mass of dry air at
the points temperature T_a and pressure p_a.
%All variables listed below were provided
p_ref=1013.246; %Normal atmospheric pressure ~1atm
T_ref=373.15; %The boiling point of water in Kelvin
e_1=11.344*(1-(T_a/T_ref));
e_2=-3.49149*((T_ref/T_a)-1);
f_1=-7.90298*((T_ref/T_a)-1);
f_2=5.02808*log10(T_ref/T_a);
f_3=(-1.3816*(10^(e_1)-1))*10^-7;
f_4=(8.1328*(10^(e_2)-1))*10^-3;
f_5=log10(p_ref);
f=f_1+f_2+f_3+f_4+f_5;
e=10^f;
w=(0.62197*e)/((p_a)-e); %The equation for calculating the mixing ratio
end
%Temperture Computation Function File (Delta_q.m) using Mixing_Ratio.m
function [Temp] = Delta_q(T)
%Delta_q computes the temperature based on the function file Mixing_Ratio and defines
global parameters to be used in the calculation of the script file Wet_Bulb.
global T_a T_d p_a
c_p=1005; %given value
L=2.501*10^6; %given value
Temp=[((L*(Mixing_Ratio(T, p_a)-Mixing_Ratio(T_d, p_a)))/(1+Mixing_Ratio(T, p_a)))-(c_p*
(T_a-T)*(1+0.8*Mixing_Ratio(T, p_a)))];
end
%Funtion File (f.m) for Root_Finder.m
function [ y ] = f( x )
%f defines the provided function to test the Root_Finder function file. This function
needs to be used as a input in the form of "@f" in the Root_Finder input arguments
%Root_Finder(@f, 0, 2) to test this function in the Root_Finder function file.
y = x^2 - 2;
end
%Root Finding Program used for Wet Bulb Program
function [x] = Root_Finder(f, a, b)
% Finds approximate roots within an absolute error of 10^-3, when you provide the
function with the inputs of:
%f(x): the continuous function in which roots need to be approximated](https://image.slidesharecdn.com/c7a2ef8b-f0fd-4c4d-8b48-1694e921c35a-161118175629/85/MATLAB-Final-Project-1-320.jpg)
![11/18/16 12:55 PM C:UsersAlexi...MATLAB_Final_Project.m 2 of 2
%[a,b]: the interval at which the function should be approximated
% then produces a single output containing the value of the approximation, x.
%To test run Root_Finder(@f, 0, 2)
c=f(a); %evaluates at the lower boundary of the interval to determine sign
d=f(b); %evaluates at the upper boundary of the interval to determine sign
if c*d>0 %Checks to see if the signs are opposite; if not displays error.
x=NaN;
else
e=1;
while e>10^-3 %defines the number of iterations that it will bisect the interval [a.b] to
approximate the root
x=(a+b)/2; %equation for bisecting the interval
y=f(x);
if c*y<0 %determines which end of the [a,b] interval needs to be bisected
b=x;
else
a=x;
end
e=(b-a)/2;
end
x=(a+b)/2;
end
end
%Program that computes the temperature based on Temperature, Dew Point, and
%Atomospheric Pressure
%%
% $x^2+e^{pi i}$ %Wet_Bulb uses the Root_Finder and Delta_q functions to compute the
temperature of wetbulb based on the globally defined parameters atmospheric temperature
T_a, dew point temperature T_d, and atmospheric pressure p_a
global T_a T_d p_a
Ta=input('Enter the current air temperature in degrees Farenheit: n');
Td=input('Enter the current dew point: n');
p_a=input('Enter the current atmospheric pressure in Hectopascals: n');
T_a=(Ta+459.67)*5/9;
T_d=(Td+459.67)*5/9;
Temperature=Root_Finder(@Delta_q, T_d, T_a) %calls the Delta_q](https://image.slidesharecdn.com/c7a2ef8b-f0fd-4c4d-8b48-1694e921c35a-161118175629/85/MATLAB-Final-Project-2-320.jpg)
MATLAB Final Project
- 1. 11/18/16 12:55 PM C:UsersAlexi...MATLAB_Final_Project.m 1 of 2 %Final Project %Ratio Funtion File (Mixing_Ratio.m) for Delta_q Funtion File function [w] = Mixing_Ratio(T_a, p_a) %Mixing Ratio calculates the ratio of the mass of water vapor to the mass of dry air at the points temperature T_a and pressure p_a. %All variables listed below were provided p_ref=1013.246; %Normal atmospheric pressure ~1atm T_ref=373.15; %The boiling point of water in Kelvin e_1=11.344*(1-(T_a/T_ref)); e_2=-3.49149*((T_ref/T_a)-1); f_1=-7.90298*((T_ref/T_a)-1); f_2=5.02808*log10(T_ref/T_a); f_3=(-1.3816*(10^(e_1)-1))*10^-7; f_4=(8.1328*(10^(e_2)-1))*10^-3; f_5=log10(p_ref); f=f_1+f_2+f_3+f_4+f_5; e=10^f; w=(0.62197*e)/((p_a)-e); %The equation for calculating the mixing ratio end %Temperture Computation Function File (Delta_q.m) using Mixing_Ratio.m function [Temp] = Delta_q(T) %Delta_q computes the temperature based on the function file Mixing_Ratio and defines global parameters to be used in the calculation of the script file Wet_Bulb. global T_a T_d p_a c_p=1005; %given value L=2.501*10^6; %given value Temp=[((L*(Mixing_Ratio(T, p_a)-Mixing_Ratio(T_d, p_a)))/(1+Mixing_Ratio(T, p_a)))-(c_p* (T_a-T)*(1+0.8*Mixing_Ratio(T, p_a)))]; end %Funtion File (f.m) for Root_Finder.m function [ y ] = f( x ) %f defines the provided function to test the Root_Finder function file. This function needs to be used as a input in the form of "@f" in the Root_Finder input arguments %Root_Finder(@f, 0, 2) to test this function in the Root_Finder function file. y = x^2 - 2; end %Root Finding Program used for Wet Bulb Program function [x] = Root_Finder(f, a, b) % Finds approximate roots within an absolute error of 10^-3, when you provide the function with the inputs of: %f(x): the continuous function in which roots need to be approximated
- 2. 11/18/16 12:55 PM C:UsersAlexi...MATLAB_Final_Project.m 2 of 2 %[a,b]: the interval at which the function should be approximated % then produces a single output containing the value of the approximation, x. %To test run Root_Finder(@f, 0, 2) c=f(a); %evaluates at the lower boundary of the interval to determine sign d=f(b); %evaluates at the upper boundary of the interval to determine sign if c*d>0 %Checks to see if the signs are opposite; if not displays error. x=NaN; else e=1; while e>10^-3 %defines the number of iterations that it will bisect the interval [a.b] to approximate the root x=(a+b)/2; %equation for bisecting the interval y=f(x); if c*y<0 %determines which end of the [a,b] interval needs to be bisected b=x; else a=x; end e=(b-a)/2; end x=(a+b)/2; end end %Program that computes the temperature based on Temperature, Dew Point, and %Atomospheric Pressure %% % $x^2+e^{pi i}$ %Wet_Bulb uses the Root_Finder and Delta_q functions to compute the temperature of wetbulb based on the globally defined parameters atmospheric temperature T_a, dew point temperature T_d, and atmospheric pressure p_a global T_a T_d p_a Ta=input('Enter the current air temperature in degrees Farenheit: n'); Td=input('Enter the current dew point: n'); p_a=input('Enter the current atmospheric pressure in Hectopascals: n'); T_a=(Ta+459.67)*5/9; T_d=(Td+459.67)*5/9; Temperature=Root_Finder(@Delta_q, T_d, T_a) %calls the Delta_q