This thesis is in two parts. In the first chapter we consider the problem of the laminar mixing of two different gases in a wall jet. Solutions of the boundary layer equations governing the radial laminar flow of a mixture of two different gases forming a wall jet are obtained. Attention is centered on that part of the flow where the concentration of one gas in the mixture is small. Further, to investigate what effect the diffusion of one gas into the other has on the velocity profile, the dominant perturbation term In the stream function is obtained by expanding the latter in terms of a parameter whose magnitude depends upon the concentration of the gas from the reservoir In the mixture. The second problem, discussed in Chapter two, is that of heat transfer in a radial liquid jet. The technique used to study this problem is similar to that employed by Watson in his investigations into the velocity distribution in a radial liquid jet. Two specific examples; are treated in detail and the results obtained, for the temperature distribution In the jet and heat transfer across the wall, are presented graphically
