RAPID FLOW OF GRANULAR-MATERIALS WITH DENSITY AND FLUCTUATION ENERGY GRADIENTS

A constitutive relationship for the stress tensor of granular material s during the rapid flow regime that includes the effects of density gr adient and fluctuating velocity is proposed. Explicit expressions for various stress components are obtained and simple examples are present ed. It is shown that this continuum-based model is capable of predicti ng normal stress differences. The model also contains many earlier mod els as its special cases. The results also show that the model may be suitable for analyzing rapid, as well as slow, motions of granular mat erials.