Joint Research Project PN-II-ID-JRP-2011-2-0060
2013 - 2016
supported by Romanian Authority for Scientific Research, CNCS - UEFISCDI
Originally, Lattice Boltzmann (LB) techniques were designed for the numerical simulation of gas flows under the assumption of local thermodynamic equilibrium. As such, they were perceived as alternatives to Navier-Stokes solvers, and even a few years ago it would have been a nonsense to think of LB approaches when dealing with so far out-of- equilibrium systems like the dispersed phase in particle-laden turbulent flows close to solid surfaces. Recently, several statistical physics and microfluidic research groups (including two partners of the present proposal) reported successful attempts to simulate the dynamics of highly rarefied gases using some of the most standard LB algorithms, with only minor changes of quadrature parameters and quadrature orders. Rapidly, these unexpected results could be theoretically understood using quite standard Knudsen expansion. This opened a new research field in which statisticians and fluid mechanicists make fruitful efforts toward further detailed understanding of the applicability range of such approaches, and toward the design of further advanced algorithms (mainly by refining the underlying discrete velocity models and boundary conditions using the physical pictures available in the microfluidic literature). The central objective of the present proposal is to initiate a similar research dynamics in the field of turbulence-particle interaction modeling, mainly thinking of today attempts to predict the deposition of particles along solid surfaces in the energy and chemical industries, notably the coal industry. Our consortium includes three research groups that have already performed two preliminary works, by pairs: one toward the non-isothermal features of far out-of- equilibrium (an essential point when addressing near-surface turbulence-driven particles) and the other toward the straightforward application of available LB algorithms to turbulence-particle interactions in academic configurations. These preliminary works established the feasibility of our approach and introduced it as a meaningful alternative to standard turbulence-transport simulation techniques (far from the solid surfaces). They also helped us defining both the theoretical and numerical orientations of the initial phase of the present proposal. Later in the project, the researches will be concentrated on the following question: how far can we manage to go toward the representation of higher temperature gradients than in the preliminary works, and, consequently, what is the full extend of the validity range of our particle-deposition modeling approach.