Wall‐to‐bed heat transfer in gas–solid bubbling fluidized beds

Effects of limestone calcination on the gasification processes in a BFB coal gasifier

“…Computational models predicting the heat-transfer coefficient in bubbling fluidised beds have also been carried out (Patil et al, 2006;Schmidt and Renz, 2000;Kuipers et al, 1992;Armstrong et al, 2010). The incorporation of the complex species transport equations and reactions within the coal gasification and combustion have been very limited due to the high computational cost of the models.…”

“…A full mathematical description of the kinetic theory is provided by Gidaspow (1994). Patil et al (2006) carried out a comparison of the KTGF with another set of closure equations for the solid-phase rheology, namely the constant viscosity model (CVM). This model assumed the particle viscosity was constant and the particle pressure was a function of the porosity of the local solid using empirical correlations.…”

CFD investigation of gas-solids flow in a new fluidized catalyst cooler

“…For example, Kuiper et al [25] obtained detailed information on the maximum bed-to-wall heat transfer occurs in the bubble wake by a two fluid model without incorporation of turbulence terms. Patil et al [26] simulated a case with a pulsating jet by incorporating a porosity profile near the wall in the thermal energy balance, based on the effective heat conductivity. And the computed local instantaneous heat-transfer coefficient was in good agreement with the experimentally determined heat-transfer coefficients.…”

The influence of multiple tubes on the tube-to-bed heat transfer in a fluidised bed

“…Numerous studies on the isothermal hydrodynamics of fluidised bed reactors have been carried out to understand the complex interactions between gas and particles (Berruti et al, 1995;Ge and Li, 2003;Samuelsberg and Hjertager, 1995;Benyahia et al, 2000;Almuttahar and Taghipour, 2008;Goldschmidt et al, 2001;Armstrong et al, 2009Armstrong et al, , 2010a. Computational modelling of heattransfer in bubbling fluidised beds has also been performed (Kuipers et al, 1992;Renz, 1999, 2000;Patil et al, 2006;Armstrong et al, 2010b,c). However, these models tend to show a strong over-prediction of the local heat-transfer coefficient compared to experimental data.…”

“…However, these models tend to show a strong over-prediction of the local heat-transfer coefficient compared to experimental data. The Eulerian-Eulerian two-fluid model (TFM) is the most frequently applied method for modelling hydrodynamics (Samuelsberg and Hjertager, 1995;Benyahia et al, 2000;Almuttahar andTaghipour, 2008, 2009;Sundaresan, 2000) and heat transfer (Patil et al, 2006;Renz, 1999, 2000;Kuipers et al, 1992) within fluidised beds. The model assumes that the gas and solid phases as continuous and fully interpenetrating within each control volume.…”