Bevel-helical speed reducer B2 gear units Overview tables Technical specification B2HH-9-C

Flender/Flender Gear Units/Bevel-helical speed reducer B2

moisture content of tent, * moist solid in equilibirum with the gasvapor mixture (zero for nonhygroscopic solids) Critical moisture content, cMoisture content at which the drying rate rst begins to drop (un- der constant-drying conditions) Humid heat Heat required to raise the temperature of unit mass of dry air and its associated vapor through 1 ( kg/H1K/H1or Btu lb/H1F/H Humidity, absolute Mass of water vapor per unit mass of dry gas (kg kg/H1or lb lb/H Humidity, relative Ratio of partial pressure of water vapor in gasvapor mixture to equilibrium vapor pressure at the same temperature Unbound moisture Moisture in solid that exerts vapor pressure equal to that of pure liquid at the same temperature Water activity, aw Ratio of vapor pressure exerted by water in solid to that of pure water at the same temperature Wet-bulb temperature, Twb Liquid temperature attained when large amounts of airvapor mixture is contacted with the surface. In purely convective dry- ing, drying surface reaches Twbduring the constant-rate period transport properties of the airwater system. In Table 2, listing of brief denitions of various terms encountered in drying and psychrometry is given. It also includes several terms not explicitly discussed in the text. Figure 1 is psychrometric chart for the airwater system. It shows the relation between the temperature (abscissa) and absolute humidity (ordinate; in kilogram water per kilogram dry air) of humid air at 1 atm absolute pressure from 0 to 1C. Lines representing the percentage of humidity and adiabatic saturation are drawn according tothe thermodynamic denitions of these terms. Equations for the adiabatic saturation and wet-bulb temperature lines on the chart are as follows (Geankopolis, : /H1Y as /H1Tas/H1/H1cs as/H1/H1.0/H1.8Y as( 1 Mujumdar and Beke Fig. 1 Psychrometric chart for the airwater system. and /H1Ywb /H1Twb/H1/H1h/ airky wb( The ratio ( / airky), the psychrometric ratio, lies between 0.9 and 1.0 for air water