PREDICTION OF HEAT AND POLLUTED MASS TRANSFER AFFECTING OPEN CHANNELS ENVIRONMENT

Abstract

The hydrodynamic model Hafez 200 I consists of the Reynolds­ average turbulent stress equations \VTitten in two-dimensional horizontal form. The finite element method is used for solving the resulting governing equations of the hydrodynamic model. An equation is developed relating the turbulent viscosity to the jet to river velocity ratio. The hydrodynamic model proved successful in predicting the circulation eddy geometry behind a jet discharging into an open channel. The predictions compared very well with the measurements for various jet to channel velocity ratios ranging from 0.63 to I 0 and jet to channel momentum ratio ranging from 0.04 to10. The latter covers a wide spectrum range of variation in practical problems. The experimental data used are those of Mikhail et al.l975, Strazisar and Prahl 1973, and the numerical data of McGuirk and Rodi 1978. With increasing velocity ratio and momentum flux, the length of recirculation zone increases as well as the inner height of the jet penetration. The successful predictions of the hydrodynamic velocity field gave confidence in using the hydrodynamic data for heat and mass predictions. This is due to the significant influence of the hydrodynamic field on the transport phenomena of either the heat or mass.