A simple collision algorithm for arbitrarily shaped objects in particle‐resolved flow simulation using an immersed boundary method

• Published in: International journal for numerical methods in fluids 2020-10, Vol.92 (10), p.1256-1273
• Main Authors: Nagata, Takayuki, Hosaka, Mamoru, Takahashi, Shun, Shimizu, Ken, Fukuda, Kota, Obayashi, Shigeru
• Format: Article
• Language: English
• Subjects: Algorithms; arbitrarily shaped particle; collision; Collision dynamics; Computation; Computer applications; Computer simulation; Conservation; Cylinders; Energy conservation; Flat plates; Flow simulation; immersed boundary; Mathematical analysis; Moving object recognition; Navier‐Stokes; particle‐laden flow; particle‐resolved simulation; Solvers; Tumbling
• ISSN: 0271-2091; 1097-0363
• DOI: 10.1002/fld.4826

Summary In the present study, we proposed a simple collision algorithm, which can be handled arbitrarily shaped objects, for flow solvers using the immersed boundary method (IBM) based on the level set and ghost cell methods. The proposed algorithm can handle the collision of the arbitrarily shaped object with little additional computational costs for the collision calculation because collision detection and calculation are performed using the level set function and image point, which are incorporated into the original IBM solver. The proposed algorithm was implemented on the solid‐liquid IBM flow solver and validated by simulations of the flow over an isolated cylinder and sphere. Also, grid and time step size sensitivity on the total energy conservation of objects were investigated in cylinder‐cylinder, cylinder‐red‐blood‐cells‐shaped (RBC‐shaped) objects, sphere‐sphere, and sphere‐flat plate interaction problems. Through validation, good agreement with previous studies, grid and time step size convergence, and sufficient total energy conservation were confirmed. As a demonstration, the drafting, kissing, and tumbling processes were computed, and it was confirmed that the present result by the proposed method is similar to the previous computations. In addition, particle‐laden flow in a channel including obstacles with collision and adhesion phenomena and the interaction of cylinders and wavy‐wall were computed. The results of these simulations reveal the capability of solving a flow containing arbitrarily shaped moving objects with collision phenomena by a simple proposed method. We proposed a simple collision algorithm, which can be handled, for flow solvers using the immersed boundary method (IBM) based on the level set and ghost cell methods. The collision algorithm that proposed in the present study is a simple and efficient. It requires only little additional costs for the computation of collision phenomena because the collision detection and calculation are performed using the level set function and image point, which are incorporated into the original IBM flow solver.