MEASUREMENT AND MODELING OF TURBULENCE IN THE GAS-LIQUID 2-PHASE ZONEDURING GAS INJECTION

Averaged and turbulent fluctuating liquid velocities in the gas/liquid plume zone of a gas-stirred water model ladle were measured with a co mbined laser Doppler anemometer (LDA) and electrical probe technique. The measured turbulence fields, void fraction distribution, and gas an d liquid velocities in the plume zone were used for evaluation of vari ous turbulence models. It was found that, among all of the turbulence models tested, only a modified k-epsilon model, with extra source term s to take into account the generation and dissipation resulting from t he interaction of the bubbles with the liquid, yielded good agreement with both the mean liquid flow field and the turbulent kinetic energy distribution. However, the values of the coefficients originally propo sed by their authors were found inapplicable to the bubbly plume situa tion; more appropriate values of the coefficients were determined base d on comparison with experimental measurement.