Mathematica 9 is now available
Student Support Forum
-----
Student Support Forum: 'Fitting Equations of state' topicStudent Support Forum > General > Archives > "Fitting Equations of state"

Help | Reply To Topic
Author Comment/Response
Steven
02/21/03 9:46pm

I am currently doing some research involving material properties @ Hi temps and pressures. I have a data set that I need to fit to the Vinet equation of state. It is of the form:

P=3*K*((V/Vo)^(-2/3))*(1-(V/Vo)^(1/3)*EXP[1.5(k-1)*(1-(V/Vo)^(1/3))]

In this equation I have values(data) involving V,P and T. The values in the above equation denoted by K and k are both functions of T. I am also able to express Vo as a function of T if necessary(that is, I can designate corresponding values for each data point). The functions K[T] and k[T] are the ones I would like to fit. I have attempted to do this but I cannot seem to get mathematica to accept the format I wish to use. Essentially I want to set up a data set where I call out all four variables P, T, V, Vo and the fit K[T] and k[T] with out adjusting or assigning coefficients to V or Vo. Is this possible in mathematica??

Thank you for your consideration,
Steven

I would then need to be able to solve this equation for V at any P and T using the functions K[T], k[T]. nad Vo[T]. I have tried even that with other EOS's and I cannot get mathematica to solve this equation. That is, I am able to assign values for P and T and cannot get the corresponding V value back out of the equation.

URL: ,
Help | Reply To Topic