Experimental Study and CFD Simulation of Heat Transfer Fixed Bed Affected by The wall: Particle Rotation and Location Effects on Hot Spots Creation Using Taguchi Method

In this study, the heat transfer of a single catalyst particle (cylindrical, sg-cylindrical, and tri-lobe) beside the bed wall was studied experimentally and numerically with the bed to particle diameter ration (N) of 4.5, 5.1, 6.7 respectively. In the numerical section, the Finite Element Method (FEM) was applied to solve the momentum, continuity, and Energy. Experimental data was used to validate the numerical results. The results showed that three are the important area around the catalyst particle: low-velocity fluid around the particle, space between the particle and bed wall, and space behind the particle. The wall effects on the heat transfer were studied by reducing the distance of the particle-bed wall. Results showed that cylindrical and sg-cylindrical particles face hot-spot for yc/Dp≤0.143 and θa=60 and θz=90 degrees are the highest probable degrees for hot-spot creation. Finally, the Taguchi method was used to find the optimized particle location around the bed wall.