SCALING PROBLEMS OF AGITATION POWER AND HEAT-TRANSFER AT THE INNER SIDE OF AN AGITATED VESSEL

A new agitation apparatus with a great agitated vessel (diameter 900 mm) was tested. The storing of the measured datas and the calculations during the measurement were made with a data aquisition system. The accuracy of the firstly used quarz temperature sensors was 0.1 K. The measurements of agitation power and heat transfer at the inner side of the agitated vessel were made only with water. Together with the earlier measurements in a little agitated vessel (diameter 297 mm) the following results are obtained: The mean scatter of all 195 measurements of the turbulent Newton number is 6,2%. The mean accuracy of the calculation model for the turbulent Newton number if 21,9%, The mean scatter of all 386 measurements of the Nusselt number is 21,7%. The calculation model for the Nusselt number is applicable for Reynolds numbers from 5 to 10(6). The mean accuracy for the coefficient of the Nusselt equation is 22.1%.