Improved filtered mesoscale interphase heat transfer model

Mesoscale structures that form in gas-solid flows considerably affect interphase heat transfer. A filtered interphase heat transfer model accounts for the effects of unresolved mesoscale structures is required in coarse-grid simulations. In the literature, researchers obtain the filtered interphase heat transfer coefficient using a correction (Q) to the microscopic interphase heat transfer coefficient. Available models are based on filtered data in the range 0 < Q < 1. However, the percentage of filtered data in the range Q < 0 and Q > 1 is non-negligible. This percentage can reach approximately 20% when the dimensionless filter size is smaller than 1.028 (66.7 x the particle diameter). We proposed an improved filtered interphase heat transfer model by considering the data in the range Q < 0 and Q > 1. We evaluated the predictive power of our model in an a priori test. Our model has much better performance than other models when the dimensionless filter size (Delta) over cap < 8.222. (C) 2021 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

An improved filtered interphase heat transfer model is proposed in this study, which takes into account the data with Q values less than 0 and greater than 1, showing better performance compared to existing models when Delta is less than 8.222.