DILUTE TURBULENT GAS-SOLID FLOW IN RISERS WITH PARTICLE-PARTICLE INTERACTIONS

Earlier work of Sinclair and Jackson that treats the laminar flow of gas-solid suspensions is extended to model dilute turbulent flow. The random particle motion, often exceeding the turbulent fluctuations in the gas, is obtained using a model based on the kinetic theory of granular materials. A two-equation low Reynolds number turbulence model is modified to account for the presence of the dilute particle phase. Comparisons of the model predictions with available experimental data for the mean and fluctuating velocity profiles for both phases indicate that the resulting theory captures many of the flow features observed in the pneumatic transport of large particles. The model predictions did not manifest an extreme sensitivity to the degree of inelasticity in the particle-particle collisions for the range of solid loading ratios investigated.