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diff --git a/src/functors/analytical/fringe3D.hh b/src/functors/analytical/fringe3D.hh
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+/*  This file is part of the OpenLB library
+ *
+ *  Copyright (C) 2015 Mathias J. Krause
+ *  E-mail contact: info@openlb.net
+ *  The most recent release of OpenLB can be downloaded at
+ *  <http://www.openlb.net/>
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version 2
+ *  of the License, or (at your option) any later version.
+ *
+ *  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 General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public
+ *  License along with this program; if not, write to the Free
+ *  Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ *  Boston, MA  02110-1301, USA.
+*/
+
+#ifndef FRINGE_3D_HH
+#define FRINGE_3D_HH
+
+#include<vector>
+#include<cmath>
+
+#include "fringe3D.h"
+
+namespace olb {
+
+template <typename T, typename S>
+Fringe3D<T,S>::Fringe3D(AnalyticalF3D<T,S>& wantedVelocity, T start, T end, int direction, T lambdaMax, T rise, T fall)
+  : AnalyticalF3D<T,S>(12), _wantedVelocity(wantedVelocity), _start(start),
+    _end(end), _direction(direction), _lambdaMax(lambdaMax), _rise(rise),
+    _fall(fall)
+{
+  this->getName() = "fringe";
+}
+
+template <typename T, typename S>
+bool Fringe3D<T,S>::operator()(T output[12], const S input[3])
+{
+
+  output[4] = T();
+  output[5] = T();
+  output[6] = T();
+  output[8] = T();
+  output[9] = T();
+  output[10] = T();
+  if ( _wantedVelocity(output, input) ) {
+    T scaleLambda = lambda(input[_direction]);
+    output[0] = -scaleLambda*output[0];
+    output[1] = -scaleLambda*output[1];
+    output[2] = -scaleLambda*output[2];
+    output[3] = scaleLambda;
+    output[7] = scaleLambda;
+    output[11] = scaleLambda;
+    return true;
+  } else {
+    output[0] = T();
+    output[1] = T();
+    output[2] = T();
+    output[3] = T();
+    output[7] = T();
+    output[11] = T();
+    return false;
+  }
+}
+
+template <typename T, typename S>
+T Fringe3D<T,S>::s(const T& x) const
+{
+  if ( x < std::numeric_limits<T>::epsilon() ) {
+    return 0.;
+  } else if (x > T(1)-std::numeric_limits<T>::epsilon() ) {
+    return T(1);
+  } else {
+    return T(1)/(T(1) + exp( T(1)/(x - T(1) ) + T(1)/x ) );
+  }
+}
+
+template <typename T, typename S>
+T Fringe3D<T,S>::lambda(const T& x) const
+{
+  return _lambdaMax*(s((x - _start)/_rise*(_end - _start) ) - s((x - _end)/_fall*(_end - _start) + T(1.)) );
+}
+
+} // end namespace olb
+
+#endif
+