Behaviour and modelling of non-spherical particles in compressible flows

• Applicant: Professor Dr. Berend van Wachem
• Subject Area: Fluid Mechanics ; Mechanical Process Engineering
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 447633787

Dispersed particles in a fluid flow are ubiquitous in nature as well as in engineering and technological applications, ranging from sediment transport in rivers to needle-free transdermal injection of pharmaceutical powders. Even though the particles in most applications have a non-spherical shape, the vast majority of research published in the literature has focused on the behaviour of spherical particles in incompressible flows. Also, a number of previous studies have investigated the behaviour of spherical particles in compressible flows, but a comprehensive understanding of the behaviour of non-spherical particles in compressible flows and their interaction with shock waves still remains elusive. In particular, a detailed understanding of the forces and torques acting on non-spherical particles in trans- and supersonic flows and due to the interaction with a shock wave is critical for understanding the physical phenomena in engineering applications involving particle-laden compressible flows, such as the quality of coatings applied by gas dynamic cold spraying or the treatment safety of transdermal drug injection, but has not been studied systematically yet. With this in mind, the primary objectives of this proposed project are a detailed analysis and quantification of (i) the forces and torques acting on stationary and moving non-spherical particles in compressible flows, and (ii) the response of single particles and arrays of particles to a passing shock wave. This will lay the foundation for a safer and more efficient design and utilisation of the relevant engineering applications. To facilitate this research, we will develop new numerical schemes in the context of the immersed-boundary method (IBM), extending the state-of-the-art by proposing a novel approach that is applicable to flows at all speeds, which eliminates common issues of IBM for compressible flows, as well as a framework for the forces and torques on non-spherical particles to be used with point-particle simulations.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Fabian Denner