Title: Numerical modeling of the impact and freezing of water droplets using lattice Boltzmann method
Start: Fall 2018
End: August 2020
Topic:
The impact and freezing of water droplets form the basis of icing on drones. This transient process involving mass and heat transfer leads to undesirable icing effects. In order to reduce the danger of operations, this phenomenon could be reduced with the use of "glaciophobic" coatings. Detailed information on such a complex process can be obtained from numerical simulation of solidification at drop scale. In this context, the Lattice Boltzmann method has emerged as a promising alternative for the simulation of multiphase flows and phase change materials.
This project focuses on a Boltzmann model on a multiphase lattice with phase change to study the impact of droplets on a cold surface followed by solidification.
Codirection: Jean-Yves Trépanier (research director) and Sébastien Leclaire (co-director)
Email: jesus.garcia-perez@polymtl.ca
Title: Impact of granular segregation on heat transfer in a rotating bed 
Start: Fall 2014
End: August 2020
Topic:
- Development of a TDEM heat transfer model for polydisperse particles
- Granular segregation in a rotating cylinder for spherical and non-spherical particles
- Study of temperature profiles for a bi-disperse particle bed in a rotary kiln
Codirection: François Bertrand (research director), Jamal Chaouki (co-director) and David Vidal (co-director)
Title: Development of a lattice Boltzmann method for the simulation of Knudsen flows applied to the optimization of the performance of nanofiber filter media
Start: May 2016
End: December 2020
Topic:
Fine particles in the air, also known as aerosols, are harmful to human health and the environment. Aerosols cause respiratory diseases and are also one of the causes of photochemical smog. Different strategies exist for capturing these particles using fibrous filters. The most promising are the use of nano-fibres, but their prohibitive cost implies a parsimonious use of such fibres. They are therefore generally mixed with or deposited on larger fibers. The formulation of such blends is often still done by trial and error, but this approach does not guarantee an optimal formulation. The numerical modeling approach for predicting the performance of fibrous filters has started to be used with some success for micron fiber blends. However, the scales involved in the use of nano-fibers mean that the gas can no longer be considered as a continuous medium and conventional fluid mechanics no longer holds. To do this, so-called Knudsen flows have to be solved and a new numerical method adapted to such flows will have to be developed in the context of complex porous media such as fibrous filters.
Codirection: François Bertrand (research director), David Vidal (co-director) and Sébastien Leclaire (co-director)
Email: jean-michel.tucny@polymtl.ca
Title: Multi-scale approach to convective drying of yeast grains: Modeling and experimental characterization of drying kinetics and quality
Start: Fall 2016
End: April 2021
Topic:
The purpose of this research is to contribute to a better understanding of the physico-chemical mechanisms taking place during the convective drying of yeast grains and to study their influence on the variation in yeast quality during drying. More specifically, the project aims to evaluate the impact of two techniques: the impact of the addition of a solid support material before drying and the intermittent regime on the drying of yeast grains.
- Characterize the effect of a solid support material on the drying kinetics of yeast grains and on yeast quality
- Assessing the impact of moisture redistribution by diffusion within granular materials on drying kinetics in intermittent regime
- To quantify the competition between capillary imbibition, gravity and evaporation within a porous medium
- To develop a multi-scale model describing the drying kinetics in a rotary aerated dryer operating in intermittent mode
Codirection: Robert Legros (research director) and François Bertrand (co-director)
Email: charlotte.van-engeland@polymtl.ca
Title: Recovery of phosphate from very fine ore by Pickering emulsification 
Start: July 2019
End: April 2020
Topic:
Froth flotation, magnetic, gravity and electrostatic separation are some known methods for beneficiation of minerals. Most of them and particularly flotation is not feasibly efficient to deal with very fine minerals which are usually adjacent to gangue of similar physicochemical properties. Such methods result either in poor efficiency or a complex and costly network of processing units.
We offered an alternative technique by Pickering emulsification through mixing reactor or solid stabilized emulsification (SSE) process to recover very fine phosphate bearing minerals from their associated gangue.
Codirection: Jamal Chaouki (research director) and Louis Fradette (research director)
Email: rahi.avazpour@polymtl.ca
Title: Facile production of HIPE gel towards 3D printed metallic porous scaffolds
Start: April 2019
End: May 2020
Topic:
Using a layer-by-layer approach, additive manufacturing (AM) can produce metal, polymer and ceramic parts for a wide variety of industries. One of the applications is to fabricate porous metallic parts for the application of aerospace, where light weight and highly durable material is required. Traditionally, metallic particle suspension is used as "ink" of 3D printer to generate pores between the metal particles during the sintering process. However, it remains a challenge to control and further increase the porosity.
High Internal Phase Emulsion (HIPE), containing over 74 vol% of dispersed phase, offers a reliable template to produce highly porous materials with specific morphology control. The droplets are densely packed together with a deformed hexagonal shape and separated by a thin layer of continuous phase and solid particle stabilizer. The nature of HIPE will not only improve the interfacial area and mechanical stability with minimum material, but also provide a solid-like flow behavior suitable for extrusion-based 3D printing system. However, extremely high intense energy (i.e. homogenizer) is devoted to generating the tiny droplets with high uniformity, which limits the production in a larger scale.
In this project, we propose a facile strategy to produce O/W HIPE ink stabilized by metal oxide nanoparticles with a low shear input, taking advantage of the formation mechanism of HIPE during mixing system. The pore morphology of the final material can be easily regulated by adjusting the formulation of the "ink" involved in the emulsification process. Further removal of internal and external phase during sintering process paves the ways for manufacturing 3D metallic hierarchical porous structure with aid of AM. The porous material obtained from this novel HIPE-templated manufacturing route is expected to produce higher and more defined porosity compared to the traditional material produced by sintered particles suspensions.
Codirection: Louis Fradette (research director)
Email: bing.wan@polymtl.ca
