public WorkingPair(AdsorbentMaterial adsorbentMaterial, AdsorbateMaterial adsorbateMaterial)
        {
            switch (adsorbateMaterial)
            {
            case AdsorbateMaterial.Water:
                switch (adsorbentMaterial)
                {
                //silica gel - water
                case AdsorbentMaterial.SilicaGel:
                    qm  = 0.40;                 // 0.4;
                    K0  = 7.3e-13;
                    Ds0 = 2.54e-4;              //m2/s
                    activationEnergy = 4.2e4;   //J/mol
                    heatOfAdsorption = 2800000; //J/Kg
                    break;

                default:
                    Console.WriteLine("no material is chosen for working pair");
                    Console.Read();
                    break;
                }
                break;

            default:
                Console.WriteLine("no material is chosen for working pair");
                Console.Read();
                break;
            }
        }
        public Adsorbent(AdsorbentMaterial adsorbentMaterial)
        {
            this.adsorbentMaterial = adsorbentMaterial;

            switch (adsorbentMaterial)
            {
            case AdsorbentMaterial.SilicaGel:
                density             = 800;   //kg/m3
                heatCapacity        = 921;   //J/kgK
                thermalConductivity = 0.198; //W/mK //0.198
                porosity            = 0.5;
                permeability        = 0.2;
                adsorbentRadius     = 1e-3; // 1.7e-4;// m
                meanFreePath        = 1e-2; //m 0.01 to 0.1 miu m
                break;

            default:
                Console.WriteLine("no material is chosen for adsorbent");
                Console.Read();
                break;
            }
        }