Pressure as a function of crank angle
12 views (last 30 days)
Show older comments
Jonathan Bird
on 23 Nov 2019
Answered: Star Strider
on 23 Nov 2019
I need to plot pressure as a function of crank angle using the following eqaution p=(pm*SQRT(1-c^2))/(1-c*cos(alpha-delta)). Ive calculated all the required variables below but Im having trouble plotting with a for loop, any suggestions please?
V_se=7000;
V_sc=250;
v=V_sc/V_se;
T_e=333;
T_c=293;
t=T_c/T_e;
phi=pi/2;
T_r=312.6;
%let V_de=1000, V_r=500, V_dc=50
V_de=1000;
V_r=500;
V_dc=50;
V_d=V_de+V_r+V_dc;
T_d=324.7;
s=(V_d/V_se)*(T_c/T_d);
B=t+1+v+2*s;
A=sqrt(t^2-2*t+1+2*(t-1)*v*cos(phi)+v^2);
c=A/B;
p_m=1.01325;
%p_max=p_m*(sqrt(1+c)/sqrt(1-c));
%p_min=p_m*(sqrt(1-c)/sqrt(1+c));
delta=atan((v*sin(phi))/(t-1+v*cos(phi)));
for alpha=0:2*pi
p=(p_m*sqrt(1-c^2))/(1-c*cos(alpha-delta));
plot (alpha,p)
end,.,.
0 Comments
Accepted Answer
Star Strider
on 23 Nov 2019
Two options for the plot, depending on what you want to do:
Plot in the loop:
figure
hold all
for alpha=0:0.2:2*pi
p=(p_m*sqrt(1-c^2))/(1-c*cos(alpha-delta));
plot (alpha,p, 'p')
end
hold off
plot (alpha,p, 'p')
xlabel('\alpha')
ylabel('p')
Plot after the loop:
alpha=0:0.2:2*pi;
for k = 1:numel(alpha)
p(k) = (p_m*sqrt(1-c^2))/(1-c*cos(alpha(k)-delta));
end
figure
plot (alpha,p, '-p')
xlabel('\alpha')
ylabel('p')
Make appropriate changes to get the result you want.
Before the plot loop (everything up to and including the ‘delta’ assignment), your code is unchanged.
0 Comments
More Answers (0)
See Also
Categories
Find more on Loops and Conditional Statements in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!