22a</a><br></p></div><!--
##### SOURCE BEGIN #####
%% RelativePermeability Class
% This class defines an abstract base class for modeling relative 
% permeability in porous media. It provides a framework for implementing 
% specific relative permeability models by defining an abstract method 
% _calculate_ that must be implemented in derived classes.
%
%% Methods
% *calculate*: Abstract method to compute the relative permeability. This 
%              method must be implemented in subclasses.
%
%% Author
% 