Effect of particle loading on heat transfer enhancement in a gas-solid suspension cross flow

Heat transfer between gas-solid multiphase flow and tubes occurs in m a ny industry processes, such as circulating fluidized bed process, pneumatic conv eying process, chemical process, drying process, etc. This paper focuses on the influence of the presence of particles on the heat transfer between a tube and g as-solid suspension. The presence of particles causes positive enhancement of h e at transfer in the case of high solid loading ratio, but heat transfer reduction has been found for in the case of very low solid loading ratio (Ms of les s than 0.05 kg/kg). A useful correlation incorporating solid loading ratio, particle s ize and flow Reynolds number was derived from experimental data. In addition, th e k-ε two-equation model and the Fluctuation-Spectrum- Random-Trajecto ry Model ( FSRT Model) are used to simulate the flow field and heat transfer of the gas-ph a se and the solid-phase, respectively. Through coupling of the two phases the mo d el can predict the local and total heat transfer characteristics of tube in gas - solid cross flow. For the total heat transfer enhancement due to particles loadi ng the model predictions agreed well with experimental data.