SIMPLIFIED MODEL TO HEAT AND MASS TRANSFER DURING ROUGH RICE DRYING IN LAPPLE CYCLONES

摘要

The basic characteristic of the rough particle flow in the cyclone is 100% ofrncollection efficiency. This phenomenon occurs because as soon as particles enter thernequipment they go to the cyclone wall and move downward to the hopper. In thisrncase, the gas-particle heat and mass transfer occur basically close to cyclone wall,rnwith same concurrent movement. Due to this fluid dynamics description, it isrnproposed in this paper a model to heat and mass transfer during the rough rice dryingrnin cyclones based on concurrent movement model. The model results are comparedrnwith the ones obtained experimentally in two Lapple cyclones using rough rice asrntest material. It was observed a good agreement between experimental and modelrnresults of air temperature and humidity as well rice grains temperature and moisturerncontent.