xdot=goveq(r,x)

% Author: Housam Binous

% Velocity Profile of Laminar Flow of Power Law fluid in a Pipe

% National Institute of Applied Sciences and Technology, Tunis, TUNISIA

% Email: [e-mail]

% governing equation is the z-component of the equation of motion in
% cylindrical coordinates and the non-Newtonian constitutive equation

function xdot=goveq(r,x)

global kappa n rend DPoverL

xdot(1)=DPoverL-x(1)/r;
xdot(2)=-(x(1)/kappa)^(1/n);

xdot=xdot';

end