Inertial Number-Based GTSH Stress Model for Predicting Gas–Solid Heat Transfer in a Bubbling Fluidized Bed

Accurate modeling of particle-phase stress and heat transfer is essential for the design and optimization of industrial fluidized bed systems. In this study, the particle flow and heat transfer behavior in a bubbling fluidized bed were investigated using the GTSH stress model based on the inertial number (INB-GTSH). The inertial number served as a transitional parameter to capture the intermediate flow regime of particles, while both interparticle friction and interstitial fluid effects during particle collisions were considered. Simulation results demonstrate that, compared to conventional solid stress models (Lun model and Agrawal model), the INB-GTSH model provides significantly improved predictions of solid mass flux, bubble dynamics, and temperature distribution, showing excellent agreement with experimental observations. The inclusion of interstitial fluid effects enhances localized particle motion, thereby intensifying heat transfer within the bed. Additionally, higher gas velocities promote better particle mixing, which contributes to a more uniform and stable heat transfer performance.