Souders-Brown capacity parameter

The term in equation 42 is called a Souders-Brown capacity parameter and is based on the tendency of the upflowing vapor to entrain Hquid with it to the plate above. The term E in equation 43 is called an E-factor. and E to be meaningful the cross-sectional area to which they apply must be specified. The capacity parameter is usually based on the total column cross section minus the area blocked for vapor flow by the downcomer(s). Eor the E-factor, typical operating ranges for sieve plate columns are... 

Values of Cp are used in (13-5) to compute the Souders and Brown capacity parameter C. Because the liquid flows contain a large percentage of absorber oil, a foaming factor, Fp of 0,75 is assumed. Also assume AJAa >0.1 so that Fha is 1.0. The value of Fst is determined from surface tension tr, which can be estimated for mixtures by various methods. For paraffin hydrocarbon mixtures, a suitable estimate in dynes per centimeter, based on densities, can be obtained from the equation... 

Entrainment Flooding The early work of Souders and Brown [Ind. Eng. Chem., 26, 98 (1934)] based on a force balance on an average suspended droplet of hquid led to the definition of a capacity parameter C,i, ... 

Equations (3.89) and (3.90) equate the tray active area vapor loading VN to the maximum VM for determining the gas in liquid entrainment flooding of the tray. The early work of Souders and Brown [12], based on a force balance on an average suspended droplet of liquid, led to the definition of a capacity parameter VM- Both VN and Where refer to the active area of the tray. This active area is simply the net tower cross-section internal area less the downcomer areas. The downcomer areas include both the downcomer inlets and outlets. 

The first term on the right-hand side of Eq. (5.7-11) has a range of values dqiending on the droplet size distribution above die two-phase mixture. For practical design purposes it is termed the capacity parameter C b. after the work of Souders and Brown. For a condition of maxhnnm vapor capacity ( entrainment flood capacity ). 

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