function KTP = ktpcalc (T,index)
% Eucken formula for thermal conductivity of polyatomic gas at low density
%
% function K = ktpcalc(T,index)
%
% Argument List:
% T [=] temperature in the units of Tdeg
% index [=] index of compounds in cnms whose coefficients are to be found
% (If this argument is omitted, all coefficients will be found.)
% Returns:
% K [=] heat transfer coefficient in units of W/m/K
%
% Ex: >> start301 (specify new session, E&M balances, ceng301 data base,
% K as temp, 1 compound: air)
% >> ktpcalc(298)
%ans =
% 0.0250
Created 3/21/95-2 Jim Lee, corrected by SHD

global mw cpv cnms
mu = mucalc(T);
T=at(T);
[row col] = size(cpv);
for counter=1:row
if isnan(cpv(counter,:))
fprintf('Heat capacity data for compound *%s* is not available.\n',cnms(counter,:))
disp('Taking heat capacity as 33.314 J/mol/K...')
Cp(counter,1) = 33;
else
Cp(counter,1) = polyval(cpv(counter,col:-1:1),T);
end
end


R = 8.3145;

if nargin==1
KTP = (Cp+1.25*R).*mu./mw*1000;
else
KTP = (Cp(index)+1.25*R).*mu(index)./mw(index)*1000;
end


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