Condensation on Coherent Turbulent Jets: Part II—A Theoretical Study

Condensation on coherent turbulent liquid jets was investigated theoretically. The governing conservation equations were obtained using an order of magnitude analysis, and were solved numerically using a finite difference method. The Boussinesq hypothesis was invoked to model turbulent transport. Various eddy diffusivity models, of varying degrees of complexity, were evaluated through comparison with experimental data, and shortcomings noted. An ad hoc model, which allows for axial decay of turbulence by viscosity, and radial decay by both surface tension and viscosity, is shown to be in reasonable agreement with experiment. Numerical solutions were also obtained for laminar jets, and are essentially exact; these solutions are used to give some insight into the nature of the jet heat transfer problem.