rotating_cone.h

Go to the documentation of this file.

/*
 * Copyright (c) 2014-2015:  G-CSC, Goethe University Frankfurt
 * Author: Andreas Vogel
 * 
 * This file is part of UG4.
 * 
 * UG4 is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License version 3 (as published by the
 * Free Software Foundation) with the following additional attribution
 * requirements (according to LGPL/GPL v3 §7):
 * 
 * (1) The following notice must be displayed in the Appropriate Legal Notices
 * of covered and combined works: "Based on UG4 (www.ug4.org/license)".
 * 
 * (2) The following notice must be displayed at a prominent place in the
 * terminal output of covered works: "Based on UG4 (www.ug4.org/license)".
 * 
 * (3) The following bibliography is recommended for citation and must be
 * preserved in all covered files:
 * "Reiter, S., Vogel, A., Heppner, I., Rupp, M., and Wittum, G. A massively
 *   parallel geometric multigrid solver on hierarchically distributed grids.
 *   Computing and visualization in science 16, 4 (2013), 151-164"
 * "Vogel, A., Reiter, S., Rupp, M., Nägel, A., and Wittum, G. UG4 -- a novel
 *   flexible software system for simulating pde based models on high performance
 *   computers. Computing and visualization in science 16, 4 (2013), 165-179"
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 */
 
#ifndef __H__UG__LIB_DISC__SPATIAL_DISC__ROTATING_CONE__
#define __H__UG__LIB_DISC__SPATIAL_DISC__ROTATING_CONE__
 
#include "lib_disc/spatial_disc/user_data/std_glob_pos_data.h"
 
namespace ug{
 
class RotatingCone2d
  : public StdGlobPosData<RotatingCone2d, number, 2>
{
  public:
    RotatingCone2d(double _eps, double _cx, double _cy, double _ax, double _ay,
                 double _nu, double _delta)
      : eps(_eps), cx(_cx), cy(_cy), ax(_ax), ay(_ay), nu(_nu), delta(_delta)
    {};
 
    inline void evaluate(number& val, const MathVector<2>& pos, number time, int si) const
    {
      const number t = time;
      const number x = pos[0];
      const number y = pos[1];
 
      const number xRot = cos(nu*t) * (x-cx) - sin(nu*t) * (y-cy);
      const number yRot = sin(nu*t) * (x-cx) + cos(nu*t) * (y-cy);
 
      const number expo = -((xRot - ax)*(xRot - ax) + (yRot - ay)*(yRot - ay)) / (delta + 4*eps*t);
      const number scale = delta/(delta+4*eps*t);
 
      val = scale * exp(expo);
    }
 
  protected:
    double eps, cx, cy, ax, ay, nu, delta;
};
 
}
#endif // __H__UG__LIB_DISC__SPATIAL_DISC__ROTATING_CONE__