Arman Seyed-Ahmadi

Research Topic

Momentum and Heat Transfer in Suspension Flows

Research Description

Particle-laden flows are ubiquitous in environmental flows, geophysical flows and man-made processes. The overall dynamics in these flows are mostly governed by the momentum, heat and mass transfer between the solid dispersed particles and the surrounding fluid. Particle-laden flows are generally quite challenging to model as they are multi-scale by nature. In fact, large structures in the flow - e.g., clustering, bubbles or shear-banding - are controlled by the local exchange at the particle level. The strong interphase coupling leads to remarkable phenomena - e.g. particle-induced turbulence or shear-induced migration. Different models corresponding to different scales of description (essentially micro, mess and macro) have been suggested in the literature, and in turn these models are associated with specific numerical methods (particle-resolved, two-way Euler-Lagrange and Euler-Euler methods respectively). The principle of multi-scale analysis is to conduct high-fidelity simulations at the micro-scale level, to extract valuable information from these data to enhance the comprehension of the flow dynamics and to use this novel comprehension to improve models at the meso-scale. A similar transfer of knowledge can be carried out from the meso-scale to the macro-scale. In the framework of a micro/meso multi-scale approach, we use our in-house simulation tools to investigate momentum and heat transfer in particle-laden flows. We perform both micro-scale and meso-scale simulations in flow regimes relevant to fluid/solid and gas/solid flows. The question of how to filter the micro-scale high-fidelity results and to develop enhanced and coherent meso-scale heat transfer models is central in this PhD project.

Why did you decide to study at UBC?

Having a global reputation for scientific research excellence and being one the leading universities in field of science and engineering in the world, this university’s active faculty and the research equipment and facilities are truly difficult to find elsewhere. A number of very well-known professors in the field of theoretical and computational fluid dynamics are running The Laboratory for Complex and non-Newtonian Fluid Flow at UBC, which I am going to attend, and they are currently doing research in areas such as particle-laden flows, interfacial fluid mechanics, bubbles and particles in yield-stress fluids and cell biomechanics. Since my interests and objectives are perfectly in line with the research conducted at this lab, collaboration with these eminent scientists enables me to learn from them, and apply my acquired knowledge to the problems at the edge of science when I graduate. Besides, living and studying in a beautiful and vibrant city like Vancouver will certainly enhance my social life, and the cultural diversity and the social texture of such a city, and of Canada in general, provides me with a life-changing and invaluable experience.

 

Why did you decide to pursue a graduate degree?

I personally derive unutterable intellectual satisfaction out of scientific work and that being the case, I aspire to be an active researcher and a productive faculty member after completing my doctoral studies. As a master’s student and while I was constantly in contact with faculty members and PhD students, I realized that the deeper and more comprehensive research goals that I had envisioned could be best fulfilled in a doctoral program. This understanding, together with my previous educational experiences and my aspiration for scientific work played the most substantial role in my decision for pursuing a doctoral degree.

What do you like to do for fun or relaxation?

Playing violin, reading, hiking.