added binary coefficients for h2o-air

dumux/material/binarycoefficients/h2o_air.hh

@@ -0,0 +1,117 @@
+/*****************************************************************************
+ *   Copyright (C) 2011 by Holger Class                                      *
+ *   Copyright (C) 2009 by Andreas Lauser                                    *
+ *   Institute of Hydraulic Engineering                                      *
+ *   University of Stuttgart, Germany                                        *
+ *   email: <givenname>.<name>@iws.uni-stuttgart.de                          *
+ *                                                                           *
+ *   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, see <http://www.gnu.org/licenses/>.   *
+ *****************************************************************************/
+/*!
+ * \file
+ *
+ * \brief Binary coefficients for water and nitrogen.
+ */
+#ifndef DUMUX_BINARY_COEFF_H2O_AIR_HH
+#define DUMUX_BINARY_COEFF_H2O_AIR_HH
+
+
+namespace Dumux
+{
+namespace BinaryCoeff
+{
+
+/*!
+ * \ingroup Binarycoefficients
+ * \brief Binary coefficients for water and nitrogen.
+ */
+class H2O_Air
+{
+public:
+    /*!
+     * \brief Henry coefficent \f$\mathrm{[N/m^2]}\f$  for air in liquid water.
+     *
+     *
+     * Henry coefficent See:
+     * Stefan Finsterle, 1993
+     * Inverse Modellierung zur Bestimmung hydrogeologischer Parameter eines Zweiphasensystems
+     * page 29 Formula (2.9) (nach Tchobanoglous & Schroeder, 1985)
+     *
+     */
+    template <class Scalar>
+    static Scalar henry(Scalar temperature)
+    {
+        Scalar r = (0.8942+1.47*exp(-0.04394*(temperature-273.15)))*1.E-10;
+
+        return 1./r;
+    };
+
+    /*!
+     * \brief Binary diffusion coefficent \f$\mathrm{[m^2/s]}\f$ for molecular water and air
+     *
+     * \param temperature the temperature \f$\mathrm{[K]}\f$
+     * \param pressure the phase pressure \f$\mathrm{[Pa]}\f$
+     * Vargaftik : Tables on the thermophysical properties of liquids and gases. John Wiley &      * Sons, New York, 1975.
+     *
+     * Walker, Sabey, Hampton: Studies of heat transfer and water migration in soils.
+     * Dep. of Agricultural and Chemical Engineering, Colorado State University,
+     * Fort Collins, 1981.
+     */
+    template <class Scalar>
+    static Scalar gasDiffCoeff(Scalar temperature, Scalar pressure)
+    {
+        const Scalar Theta=1.8;
+        const Scalar Daw=2.13e-5;  /* reference value */
+        const Scalar pg0=1.e5;     /* reference pressure */
+        const Scalar T0=273.15;    /* reference temperature */
+        Scalar Dgaw;
+  
+        Dgaw=Daw*(pg0/pressure)*pow((temperature/T0),Theta);
+
+        return Dgaw;
+    };
+
+    /*!
+     * Lacking better data on water-air diffusion in liquids, we use at the
+     * moment the diffusion coefficient of the air's main component nitrogen!!
+     * \brief Diffusion coefficent \f$\mathrm{[m^2/s]}\f$ for molecular nitrogen in liquid water.
+     *
+     * The empirical equations for estimating the diffusion coefficient in
+     * infinite solution which are presented in Reid, 1987 all show a
+     * linear dependency on temperature. We thus simply scale the
+     * experimentally obtained diffusion coefficient of Ferrell and
+     * Himmelblau by the temperature.
+     *
+     * See:
+     *
+     * R. Reid et al.: "The properties of Gases and Liquids", 4th edition,
+     * pp. 599, McGraw-Hill, 1987
+     *
+     * R. Ferrell, D. Himmelblau: "Diffusion Coeffients of Nitrogen and
+     * Oxygen in Water", Journal of Chemical Engineering and Data,
+     * Vol. 12, No. 1, pp. 111-115, 1967
+     */
+    template <class Scalar>
+    static Scalar liquidDiffCoeff(Scalar temperature, Scalar pressure)
+    {
+        const Scalar Texp = 273.15 + 25; // [K]
+        const Scalar Dexp = 2.01e-9; // [m^2/s]
+        return Dexp * temperature/Texp;
+    };
+};
+
+}
+} // end namepace
+
+#endif