function [phihs] = hinderedsettlingfactor(c, cgel)
%HINDEREDSETTLINGFACTOR reduction in settling velocity due to gelling
%
%   [phihs] = hinderedsettlingfactor(c, cgel)
%
%   c: mass concentration (kg/m^3)
%   cgel: gelling mass concentration (kg/m^3), between 130 and 1722 kg/m^3
%
%   The relation used here is published by Van Rijn (2007a,b)
%
%   Example:
%   phihs = hinderedsettlingfactor(1,2650, 1)
%
% References
%   Van Rijn, L., 2007a. Unified View of Sediment Transport by Currents and
%   Waves. I: Initiation of Motion, Bed Roughness, and Bed-Load Transport.
%   Journal of Hydraulic Engineering, 133(6), 649-667
%
%   Van Rijn, L., 2007b. Unified View of Sediment Transport by Currents and 
%   Waves. II: Suspended Transport. 
%   Journal of Hydraulic Engineering, 133(6), 668-689.

%% Copyright notice
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%   Copyright (C) 2010 Alkyon Hydraulic Consultancy & Research
%       grasmeijerb
%
%       bart.grasmeijer@alkyon.nl	
%
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%
%   This library is distributed in the hope that it will be useful,
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%% Version <http://svnbook.red-bean.com/en/1.5/svn.advanced.props.special.keywords.html>
% Created: 14 Jul 2010
% Created with Matlab version: 7.10.0.499 (R2010a)

% $Id$
% $Date$
% $Author$
% $Revision$
% $HeadURL$
% $Keywords: $

%%

phihs = (1-0.65.*c./cgel).^5;

