3. Model to predict agglomeration and defluidization

The aim of this work is modeling the high-temperature defluidization behavior of iron powders involving the effects of gas velocity and gas properties. The calculation is focused on the evolution of forces acting on particles with temperature based on the surface viscosity and bubble motion. By analyzing the experimental data with a statistical regression, a force balance model is developed to describe the defluidization processes in a fluidized bed, by which the temperature dependence of the defluidization behavior is predicted.

### 3.1. Modeling defluidization phenomena
