calc_density.m

function [density, density_f] = calc_density(T,Tf,p,pf)
%  Calculate the pressure and temperature dependent density of the fluid.
%  The equation of state follows the work of Hongbing et al. (2008)
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%  Authors: Gunnar Jansen, University of Neuchatel, 2016 
%
%  calc_density(T, Tf)
%
p = max(p./1e6, 0.1);
pf = max(pf./1e6, 0.1);

density = 9.992e2 + 9.539e-2.*T - 7.618e-3.*T.*T - 4.336e-1.*p + 1.762e-3.*p.*p;
density_f = 9.992e2 + 9.539e-2.*Tf - 7.618e-3.*Tf.*Tf - 4.336e-1.*pf + 1.762e-3.*pf.*pf;