Film condensation inclined plate

Control volume used in setting up force balance for a condensed film on an inclined plate. 

Equations for vertical plates can also be used for laminar film condensation on Ihc upper surfaces of the plates that are inclined by an angle 0 from llie vertical, by replacing g in that equation by g cos 9. Vertical plate equations can also be used to calculate the average heat transfer coefl icieni for laminar film condensation on the outer surfaces of vertical tubes provided that the tube diameter is large relative to the thickness of the liquid film. 

Laminar film condensation on vertical or inclined plates, and on the inside or outside of a vertical tube. 

A 30-cm high by 150-cm wide plate is maintained at 5°C and is inclined at 45° from the vertical. Calculate the rate of condensation, the heat transfer rate, and the maximum film thickness when the plate is exposed to stagnant saturated water vapor at 20°C. Do die calculation both with and without the effect of film subcooling. What is the value of the Jakob number for this problem ... 

Shigechi et al. [112] conducted a boundary layer analysis of this problem and included momentum and convection effects in the condensate film. They obtained different solutions using as a boundary condition various inclination angles of the liquid-vapor interface at the plate edge. Their maximum average Nusselt number was found to agree well with Eq. 14.98. Chiou et al. [214] included surface tension in their model and showed that heat transfer decreases in relation to Eq. 14.98 as the surface tension of the condensate increases. 

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