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ODE system solving
From: |
address@hidden |
Subject: |
ODE system solving |
Date: |
Fri, 07 Jan 2005 11:35:28 +0000 |
hi everybody
i need to solve a differential equation system, 1 first order equation and 1
second order equation.
they are in the form
w"=f(z,w,w',T,T')
T'=f(z,w,T)
w,w',w",T,T' are function of z.
i have 3 initial condition w0,w'0, T0.
in the rfirst equation i make the substitution
w --> y1
w'--> y2, so w" --> y2'
T --> y3, so T' --> y3'
the system became a 3 first order equation system, is it right?
this is the m-file section:
SysO(1)=y(2);
SysO(2)=y(1)*y(2)/(3*Nup)-(g/(3*Nup))+(2*tau/(3*Nup*rho*Rz))+((y(2)^2)/y(1)*3*Nup)-(1/Nup)*dNup*y(2)*(-2*hc*(y(3)-Ta)/(Rz*rho*Cp*y(1)));
SysO(3)=-2*hc*(y(3)-Ta)/(Rz*rho*Cp*y(1));
as you can see, the second equation (SysO(2)) is dependent of T': in fact the
last term of the second equation is the same of the third equation.
the question is: is this m-file correct?
of course in the m-file i have all the other equations (Rz, Nup....). they are
function of w and T.
in solving the system i receive a "tolerance not met" error message. can you
help me?!?!?
thanks
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