Development and application of computational method for transport of non-spherical particles in gas-solid fluidized bed with large temperature difference

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K20284
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 60100:Computational science-related
• Research Institution: Kyoto University
• Principal Investigator: Daisuke Toriu 京都大学, 学術情報メディアセンター, 助教 (60772572)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 流体・固体熱連成 / 低マッハ数圧縮性流れ / 流動層 / 音速抑制法 / 直交格子法

Outline of Final Research Achievements

In this study, a computational method for interactions between low Mach number flows and arbitrary shaped particles is developed to conduct particle scale computations for the transport of non-spherical particles in gas-solid fluidized beds with large temperature differences. The fractional step method with the reduced speed of sound technique is used for fluid computations, and a Cartesian grid method with the DF/FD method is used for computations of fluid-solid interactions. Several numerical experiments were conducted to confirm basic characteristics of the proposed method. The computational results show that the proposed method can accelerate computations while keeping the impact on the computational results sufficiently small by setting appropriate parameters to reduce the speed of sound, and that can stably calculate particle transport phenomena due to flows with large temperature differences about 100 ℃.

Free Research Field

計算力学

Academic Significance and Societal Importance of the Research Achievements

複雑な流動層の流動化メカニズムを解明するために，近年では固体粒子よりも十分に小さい流体計算格子を設定し，粒子周りの微視的な流れと粒子個々の運動を直接計算する手法が検討されている．しかし，大きな温度変化による気体の密度変化（圧縮性）や固体粒子形状の影響を考慮したものは少ない．本研究で開発した手法を発展させることで，これらの影響を考慮しつつ高温固気流動層内の微視的な温度分布や流速分布，各粒子に働く流体力や接触力など，実験では得ることの難しい精緻なデータの取得が可能となることが期待される．