A NEW GENERAL APPROXIMATE SOLUTION FOR THE HEAT AND MASS-TRANSFER IN LAMINAR MULTICOMPONENT BOUNDARY-LAYERS OF THE FLATE PLATE

The heat and mass transfer between a laminar multicomponent boundary l ayer and a flat plate with arbitrary injection and suction through the plate surface can be approximately described by the exact film theory of Krishna and by a theory based on a frictionless current only. A co mparison shows that the results of these approximate solutions can dif fer significantly from numerical results calculated from the full set of differential equations for this problem. A new approximate solution based on a linear increasing velocity profile is introduced with its own correlation for the velocity gradient. This new approximate soluti on reproduces the results of the differential equations for constant f luid properties extremly well. The variation of the properties with re spect to temperature and concentration can be accounted by the use of suitable reference properties. For the estimation of these reference p roperties methods are presented.