| | The function is:||
function yprime = model(t,y)d=5*10^-6; xHe=0:1:100; %Important
xAr=100:-1:0; %Important
pg=(1.5979.*xAr)+(.1624.*xHe); V=(pi/6)*d^3; As=(pi/4)*d^2; Ad=(pi*d^2); g=9.81; pm=3545; CM=0.2165; yg=1.66; Po=2.76; Pe=0.0018; Ma=CM*(sqrt((2/(yg-1))*(((Po/Pe)^((yg-1)/yg))-1))); mmolg=((40.*xAr)+(4.*xHe))./1000;R=8.314; To=300; Te=To/(1+((yg-1)/2)*(Ma^2)); vs=sqrt(((yg*R*Te)./(mmolg))); vgo=Ma.*vs; k=(3.04*(10^-4)).*(vgo.^1.24); e=0.035; s=5.671*10^-8; Kg=(.0179.*xAr)+(.15015.*xHe); Cpg=(520.76.*xAr)+(5278.*xHe); ug=((224.3*10^-6).*xAr)+((198.6*10^-6).*xHe); Tgas=370;yprime(1,1)=y(2); CD=(.28+(((6.*(sqrt(((pg.*d.*(abs((vgo.*exp(-y(1)./k))-y(2))))./ug))))+21)./((pg.*d.*(abs((vgo.*exp(-y(1)./k))-y(2))))./ug))); yprime(2,1)=(V.*(pm-pg).*g-(0.5.*pg.*As.*CD).*(abs(y(2)-(vgo.*exp(-y(1)./k)))).*(y(2)-vgo.*exp(-y(1)./k)))./(pm*V); vg=vgo.*exp(-y(1)./k); vd=y(2); Re=((pg.*d.*(abs(vg-vd)))./ug); Pr=(ug.*Cpg)./Kg; h=(Kg./d).*(2+0.6.*(Re.^.5).*(Pr.^(1/3)));Cpd=(21.8+.009.*y(3)); fr=.043;yprime(3,1)=fr.*((-h.*Ad*(y(3)-Tgas))-(Ad.*e.*s.*((y(3).^4)-Tgas.^4)))/(V.*pm.*Cpd);_ | |The script to solve the function is:||_y0(1,1)=0; y0(2,1)=0; y0(3,1)=1373; xHe=0:1:100; %Important xAr=100:-1:0; %Important pg=(1.5979.*xAr)+(.1624.*xHe); g=9.81; pm=3545; CM=0.2165; yg=1.66; Po=2.76; Pe=0.0018; Ma=CM*(sqrt((2/(yg-1))*(((Po/Pe)^((yg-1)/yg))-1))); mmolg=((40.*xAr)+(4.*xHe))./1000; R=8.314; To=300; Te=To/(1+((yg-1)/2)*(Ma.^2)); vs=sqrt(((yg*R*Te)./(mmolg))); vgo=Ma.*vs; k=(3.04*(10^-4)).*(vgo.^1.24); Kg=(.0179.*xAr)+(.15015.*xHe); Cpg=(520.76.*xAr)+(5278.*xHe); ug=((224.3*10^-6).*xAr)+((198.6*10^-6).*xHe); Tgas=370; Pr=(ug.*Cpg)./Kg; fr=.043; tspan1=[0,.005]; [t1,y1]=ode45('model',tspan1,y0); d1=5*10^-6; z1=y1(:,1); vd1=y1(:,2); vg1=vgo.*exp(-z1./k); T1=y1(:,3); Re1=((pg.*d1.*(abs(vg1-vd1)))./ug); Cpd1=21.8+(0.009.*T1); h1=(Kg/d1).*(2+0.6.*(Re1.^.5).*Pr.^(1/3)); Tdot1=mean((6*fr*(T1-Tgas).*h1)./(pm*Cpd1.*d1)); semilogy(xHe,Tdot1,'b*')
_ | The error I get is:|_
>> solve_modelSubscripted assignment dimension mismatch.Error in model (line 31)yprime(2,1)=(V.*(pm-pg).*g-(0.5.*pg.*As.*CD).*(abs(y(2)-(vgo.*exp(-y(1)./k)))).*(y(2)-vgo.*exp(-y(1)./k)))./(pm*V);Error in odearguments (line 87)f0 = feval(ode,t0,y0,args{:}); % ODE15I sets args{1} to yp0.
Error in ode45 (line 113)[neq, tspan, ntspan, next, t0, tfinal, tdir, y0, f0, odeArgs, odeFcn, ...Error in solve_model (line 31)[t1,y1]=ode45('model',tspan1,y0);
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