Impingement plates calculation

Calculate the pressure drop for the conditions of Example 7.20. Assume that the nozzle velocities are 5 ft/s (1.52 m/s), that the fluid density is 55 lb/ft3 (881 kg/m3), and that there are 24 baffles. Assume that there is also an impingement plate at the inlet nozzle. Calculate the pressure drop for both fouled and clean conditions. 

Reinders and his coworkers assume that the silver atoms sublimated onto the glass plate adhere to it at the point of contact. They then calculate on a probability basis the number of atom pairs, triplets, etc. expected per unit area from the total number of atoms impinging upon that area. They assume that a pair is formed only if the second atom strikes the first or if it strikes the glass at a distance from the first not greater than the normal distance between adjacent atoms in the silver crystal. Experimentally, they find that the number of developed nuclei corresponds closely with the calculated number of initial centers containing four or more atoms. A recalculation of their data based on a more accurate probability treatment (Berg, 43) does not materially change the result. 

On entering the chamber C the ions are bent in a circular path, (refer to side view of fig. 1) pass through the slit M which is 1 mm. wide, and impinge on the plate N which makes electrical coimection with the insulated quadrants of the electrometer. The electrometer was the Compton t q5e, specially constructed in this laboratory. With a 75 volt potential on the vane, the electrometer had a sensitivity of 6500 divisions per volt. Under the conditions prevailing dining these experiments, this gave a calculated current sensitivity of 1 X 10 amperes. 

Fig. 10.3. Relaxation times for concentration boundary layer. t and hydrodynamic boundary layer, t , calculated for an aqueous flow (i/= 1.0 x 10 Jcnrs-1, D = 1 x 10 cm2 s 1) at 10cm s 1 impinging on the edge of a plate with an embedded electrode set 1 cm back from the plate edge.

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