Modelling of the solids flow in a blast furnace

A model to describe the solids flow under blast furnace conditions with cou ntercurrent gas flow is developed on the basis of fluid mechanics and the p rinciples of solid mechanics. The surface stress resulting from the interac tion among flowing particles is considered to be composed of two parts: rat e-dependent and rate-independent. The concept of viscosity is extended to s olids flow To represent the hydrodynamic particle-particle interaction (rat e-dependent part), and the concept of solid plastic modulus and Coulomb fri ctional stress relation are employed to describe the frictional contact int eraction (rate-independent part). Moreover, a method is proposed to determi ne the transition between moving and non-moving zones, i.e. the profile of stagnant zone. The validity of the model is demonstrated by the good agreem ent between the model predictions and measurements obtained from a cold phy sical model of a blast furnace under various flow conditions.