Volume humid

The humidity term and such derivatives as relative humidity and molal humid volume were developed for the air—water system. Use is generally restricted to that system. These terms have also been used for other vapor—noncondensable gas phases. 

In Figure 2 the lines, volume, m /kg dry air, indicate humid volume, which includes the volume of 1.0 kg of dry gas plus the volume of vapor it carries. Enthalpy at saturation data are accurate only at the saturation temperature and humidity however, for air—water vapor mixtures, the diagonal wet bulb temperature lines are approximately the same as constant-enthalpy adiabatic cooling lines. The latter are based on the relationship ... 

Humid volume is the volume in cubic feet of 1 lb of dry air and the water vapor it contains. 

Saturated volume is the humid volume when the air is saturated. 

Humid volumes are given by the curves entitled Volume mVkg diy air. The volumes are plotted as func tions of absolute humidity and temperature. The difference between dry-air specific volume and humid-air volume at a given temperature is the volume of water vapor. 

Saturated volume is the volume in cubic feet of 1 lb of dry air when it is saturated with water vapor that is, it is the humid volume at saturation, and is determined by the temperature and pressure. The humid volume of air equals the product of its saturated volume at its dew point and the ratio of the absolute temperature of the air to the absolute temperature of its dew point. 

The saturated volume at 100 F is then 14.09+0.97 = 15.06. A eurve of sueh values is shown in Figure 28. Sinee humid volume is defined as the volume of any mixture, expressed as eubic feet of mixture per pound of dry air, and since both the specific and saturated values are on the basis of 1 lb of dry air, the humid volume for any humidity may be obtained directly by interpolation between the curves for specific and saturated volumes. 

Humid volume, is the volume of unit mass of dry air and its associated vapour. 

Once the analytical method is validated for accuracy at the laboratory scale, it can be used to obtain extensive information on process performance (blend homogeneity, granulation particle size distribution, and moisture content) under various conditions (blender speed, mixing time, drying air temperature, humidity, volume, etc.). Statistical models can then be used to relate the observable variables to other performance attributes (e.g., tablet hardness, content uniformity, and dissolution) in order to determine ranges of measured values that are predictive of acceptable performance. 

The humid volume is the volume of lib of dry air plus the volume of its associated water vapor,... 

The humid volume of a gas-vapor mixture is the volume, in ft3, of 1 lb of dry gas and its accompanying vapor at the prevailing temperature and pressure. From the ideal gas law we can write the following ... 

The diagonal lines that run upward and to the left of the saturation curve in Figure 2.5 are referred to as adiabatic cooling curves. Lines for the specific volume of dry air and the saturated volume are also shown. Coordinates of points on these lines are computed by use of Equation 2.38. The humid volume of unsaturated air can be determined by linear interpolation between the two lines, based on percentage humidity. 

The humid volume of the air stream is determined by locating points F and G on the saturated and dry-volume curves, respectively, which correspond to... 

The reader should be familiar with the use of the air-water psychrometric chart (Figure 2.5). If not, the reader should take a look at some of the problems at the end of Chapters 2 and 3. By way of review, the basic chart consists of a humidity(>/)-temperature (dry-bulb) set of coordinates along with additional parameters (curves) of constant relative humidity, constant moist volume (humid volume), adiabatic cooling curves (which are the same as the wet-bulb or psychrometric lines, for water vapor only) and the 100% relative humidity curve, also called the saturated-air curve. If any two values are known, we can determine the air-moisture condition on Figure 2.5 and evaluate all other required parameters. 

Develop a simple expression for the humid volume of moist air. 

The temperature and dew point of the air entering a certain dryer are 130 and 60°F (328 and 289 K), respectively. Using a humidity chart (Fig. 19.9), find the following properties of the air its humidity, its percentage humidity, its adiabatic-saturation temperature, its humidity at adiabatic saturation, its humid heat, and its humid volume. 

Find the humid volume. Erect a perpendicular through the abscissa (along the bottom of the graph) that corresponds to 130°F, the dry bulb temperature. Label the intersection of this perpendicular with the saturated-volume-versus-temperature line as point D, and the intersection of the perpendicular with the specific-volume-dry-air-versus-temperature line as point E. Then, along line ED, find point F by moving upward from point by a distance equal to... 

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