B2-HV-16-D tables Technical specifications continued Actual Bevel-helical gear boxes B2

Flender/Flender Gear Units/Bevel-helical gear boxes B2

n if the thin-layer kinetics are internally controlled. Brooker et al. ( have discussed various deepbed-drying models for grains; the reader is referred to thisreference and others for details. 2 CLOSING REMARKS Dryer calculations require knowledge of various thermophysical properties and quality parameters; these are integral parts of other chapters in this handbook. The reader is re- ferred to the website FLENDER GRAFFENSTADEN geocities speed reducers/drying guru/ for information about current sources and resources useful in the selection, design, and operation of dryers. NOMENCLATURE evaporation area, m2 aw water activity, /H1 empirical constant cp specic heat, kg/H1K/H1 cs humid heat, kg/H1K/H1 empirical constant DL effective diffusivity, m2s/H1 DLO effective diffusivity at reference temperature, m2s/H1 Ea activation energy, Hw enthalpy of wetting, kg/H1 convective heat transfer coefcient, /H1K/H1 empirical constant kg thermal conductivity, /H1K/H1 ky convective mass transfer coefcient, kg mol /H1m/H1mol frac/H1 Mair molar mass of air, kg mol/H1 Ms mass of bone dry solid, kg , empirical constant drying rate, kg /H1h/H1 vapor pressure of pure water, Pa partial pressure, Pa pw equilibrium vapor pressure of water, Pa RH relative humidity, decimal fraction, /H1 Rg universal gas constant, 8.3 mol/H1K/H1 temperature, Grain Drying Basics 1 Tabs absolute temperature, Twb wet-bulb temperature, (or ) time, (or ) total moisture content, kg water/kg dry solid, /H1 Xc critical moisture content, kg water/kg dry solid, /H1 average moisture content, kg water/kg dry solid, /H1 Xf free moisture content, kg waer/kg dry solid, /H1 * equilibrium moisture content, kg water/kg dry solid, /H1 absolute air humidity, kg water vapor/kg dry air Greek letters normalized drying rate, /H1 latent heat of vaporization, kg/H1 dynamic viscosity, kg /H1s/H1 normalized drying rate, /H1 density, kg /H1 Subscripts constant rate period falling rate period gas initial solid vapor water wb wet