Non-Spherical Particles in Turbulence

Non-spherical particle-turbulence interactions are common in many environmental, technological and biological applications. In some cases, these particles can be modeled as spherical ones, but in many other cases, e.g. microplastics dispersion, ice crystals in the atmosphere and composite material fabrication, the non-sphericity and associated alignment is governing the dispersion, light reflection or material strength. Much progress has been made in our understanding of the interaction of non-spherical particles in turbulence. However, due to the non-trivial interaction of these particles with turbulent flow structures that may be characterized by preferential sampling of flow regions (in the case of inertial particles) as well as preferential alignment with turbulent flow structures, still many questions remain unanswered, especially in non-homogeneous turbulent flows. Numerical simulations supported by theoretical and experimental results have been leading the way. However, both numerical and experimental methods have been advancing at a rapid pace and experiments are currently able to catch up with numerical simulations or even surpass them, especially at high Reynolds number applications. As a consequence of these developments, it is now useful to look back and review the many studies on the subject to survey the current state of research and put future research paths in perspective. The course aims to provide a general and unified framework of state-of-the-art theoretical, numerical and experimental techniques for the study of the dynamical behavior of non-spherical particles in turbulent flows. Participants will be exposed to the different methodologies and approaches, their strengths and weaknesses, thus becoming more aware of the capabilities and limitations of the different approaches. Only by understanding the capabilities and shortcomings of the employed methodologies, one can achieve synergy between the different approaches and as a result further advance our understanding of the complex interaction of non-spherical particles with turbulent flows. A comprehensive ensemble of applications, mainly extracted from the lecturers’ own research field and covering several areas of applied physics and engineering, will also be provided. After the lectures, students should possess the necessary knowledge of the basic capabilities, potentials and limitations of the various addressed numerical and experimental methods and, hence, should be able to critically evaluate the reliability and accuracy of the information these methods can provide when applied to practical situations. The course delivers a comprehensive overview of complex particle-laden turbulent flows, and hence will be particularly attractive to graduate students, PhD candidates, young researchers, and faculty members in applied physics, applied mathematics and chemical/mechanical engineering. The advanced topics and the presentation of current progress in this very active field will also be of considerable interest to many senior researchers, as well as industrial practitioners having a strong interest in understanding the multi-scale complex behavior of such multiphase flows, with particular emphasis on their modelling, simulation, and experimentation.