A semi-transient dual time stepping method for the simulation of particle laden flows

• Eulerian-Lagrangian method is applied to simulate powder coating applications. • Multi time-scale approach allows the solver to be efficient for process development. • Decoupled Eulerian field/particle motion simulations suits parameter studies. • Cloud computing integration enables efficient large-scale parameter studies. In the simulation of particle-laden flows, the permissible time step varies by several orders of magnitude between the dynamic motion of the particles and the transient flow. Therefore, adaptive and/or multi-time step methods are necessary to enhance the computational performance of such simulations. This study introduces a novel semi-transient dual time stepping method (STDTM) specifically for the industrial application of powder coating. Applying a uniform coating of a specific thickness on geometrically complex shapes presents significant challenges in powder coating. Traditional experimental trial-and-error methods can be costly in the design process and often provide limited insights. Consequently, numerical simulations are essential for conducting parametric studies that can refine the design space and identify optimal parameters. STDTM is developed to address these challenges, particularly for performing parametric studies in a cloud-based environment. A mock parametric study conducted within this research demonstrated a computational performance increase of up to 100 times. Additionally, the impact on accuracy has been thoroughly examined, with further improvements suggested to mitigate any accuracy penalties.