タナカ　トシツグ   Toshitsugu Tanaka   田中　敏嗣    所属   追手門学院大学  理工学部 機械工学科    職種   教授
発表年月日	2025/07/02
発表テーマ	On the modelling of cohesion force for DEM-CFD simulation of fluidized behavior of cohesive particles
会議名	The 10th International Conference on Discrete Element Methods (DEM10)
主催者	The Society of Powder Technology, Japan
学会区分	国際学会
発表形式	口頭（招待・特別）
単独共同区分	共同
招待講演	招待講演
国名	日本
開催地名	HImeji, Japan
開催期間	2025/07/01～2025/07/05
発表者・共同発表者	Toshitsugu Tanaka1, Kaito Kudo, Kimiaki Washino, Takuya Tsuji
概要	In the context of DEM simulations of granular processes, the spring constant of the DEM contact force model is frequently reduced to reduce computational expense (Tsuji, Kawaguchi, Tanaka, 1993). This is due to the fact that decreasing the spring constant necessitates an increase in the time step required for numerical simulation. Kobayashi et al. (2013) have noted that reducing the spring constant can encourage agglomeration in the flow behavior of cohesive particles. To address this challenge, they have proposed the dynamic adhesion force model (DAFM) for adhesive particles. This model was theoretically derived to ensure that the collisional motion of particles with reduced spring constants is equivalent to that of the original particles. Tanaka et al. (2024) have demonstrated the validity of DAFM for the contact-dominated regime of cohesive granular shear flow and have shown that the bond-breaking model proposed in their study accurately describes the validity of DCFM in the contact-dominated regime. The validity of the bond-breaking model indicates that the effects of cohesion force on the dynamic behavior of cohesive particles are predominantly influenced by the bond energy between the particles. In this study, a DEM-CFD simulation of the fluidized behavior of cohesive particles is conducted using the DAFM with a linear spring-dashpot and a simplified JKR, both of which possess a common bond energy. It is demonstrated that the formation and behavior of aggregates in a fluidized state are governed by the bond energy. Furthermore, the restriction of reduction in elasticity aligns closely with the criteria established by Tanaka et al. (2024).