Example  Plotting a Cone using Cylindrical Coordinates

clc
clear
M=20;
N=20;
t0=0;
t00=2*pi;
dt=(t00-t0)/M;
R=0.2;
t=(t0:dt:t00);
%Using two for loops to generate the discrete angles
for i=1:M;
p=0;
for j=1:N;
p=p+dt;
t(i,j)=p;
end
end
for i=1:M;
for j=1:N;
x(i,j)=R*cos(t(i,j));  
y(i,j)=R*sin(t(i,j));
z(i,j)=1;
end
end
plot3(x,y,z,'r*')
grid on
axis equal
R1=0
for i=1:M;
for j=1:N;
x1(i,j)=R1*cos(t(i,j));
y1(i,j)=R1*sin(t(i,j));  
z1(i,j)=1.2;
end
end
hold on
plot3(x1,y1,z1,'r*')

Laminar Combustion Velocity Calculatour.
Burning Velocity Calculation.
This example covers the change of both temeprature and pressure at the same time.

Methane Burning Velcoity

clc
clear
%Burning Velocity for Methane/air combustion
alphap=-0.504;
alphaT=2.105;
%choosing the number of points
N=10;
DT=400-300;
DP=10/1;
dt=DT/N;
dp=DP/N;
T(1)=300;
P(1)=1;
for i=1:N;
%Data Range Generation    
T(i+1)=T(i)+dt;
P(i+1)=P(i)+dp;
%Constant Value Cells
P0(i)=1;
SL0(i)=0.259;
T1(i)=300;  
%formula algebric simplification
a(i)=P(i)/P0(i);
b(i)=T(i)/T1(i);
aa(i)=(a(i))^alphap;
bb(i)=(b(i))^alphaT;
%Putting the formula togather
SL(i)=SL0(i)*aa(i)*bb(i);
end
plot(SL,T(1:N),'-*')
grid on
xlabel('Burning Velocity (m/s)')
ylabel('Temperature (K)')
title('Methane Burning Velocity versus (Temperature+Pressure)')

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Example  Plotting Concenration in a 2D plane.

clc
clear
LX=1;
LY=1;
LZ=1;
N=50;
M=50;
L=50;
DX=LX/M;
DY=LY/N;
DZ=LZ/L;
for i=1:M;
for j=1:N;
n(i,j)=rand(1,1)*exp(-0.001*i*j);
end
end
for i=1:M;
for j=1:N;
V(i,j)=DX*DY*DZ;
C(i,j)=n(i,j)/V(i,j);
end
end
contour(C,12)
title('Concentration in a 2D Domain')
xlabel('X')
ylabel('Y')

Example

clc
clear

LX=1;
LY=1;
LZ=1;

N=50;
M=50;
L=50;

DX=LX/M;
DY=LY/N;
DZ=LZ/L;

A=2000;
EA=3000;
R=8314;


for i=1:M;
    for j=1:N;
        ppp(i,j)=rand(1,1);
        na(i,j)=ppp(i,j)*exp(-0.001*i*j);
        nb(i,j)=1-na(i,j);
        T(i,j)=300*((i*DX)^2)%+2*i*DX);
    end
end

for i=1:M;
    for j=1:N;
        Volume(i,j)=DX*DY*DZ;
        CA(i,j)=na(i,j)/Volume(i,j);
        CB(i,j)=nb(i,j)/Volume(i,j);
    end
end

for i=1:M;
    for j=1:N;
        P(i,j)=-EA/R*T(i,j)
        K(i,j)=A*exp(P(i,j));
        V(i,j)=K(i,j)*((CA(i,j))^na(i,j))*((CB(i,j))^nb(i,j))
    end
end

figure(1)
contour(CA)
title('Concentration in a 2D Domain')
xlabel('X')
ylabel('Y')
figure(2)
contour(CB)
title('Concentration in a 2D Domain')
xlabel('X')
ylabel('Y')
figure(3)
contour(V)
title('Speed of Reaction in a 2D Domain')
xlabel('X')
ylabel('Y')
grid on
pause(10)
close all

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