MOdelling of REactive particulate flows for Low Energy Sustainable processeS – MORE4LESS

The overall approach is based on a three-scale decomposition, each one with appropriate models at each scale:microscopic (micro) scale, where the flow around each solid particle is fully resolved, mesoscopic (meso) scale, using an Euler/Lagrange approach, macroscopic (macro) scale, using An Euler/Euler approach.
The partners of the project have developed various numerical tools at the three different scales. At the meso scale, in moderate-to-dense regimes, models accounting for either chemical reactions or heat transfer are still missing. These models are needed for improving the closure laws at macro scale.
The strategy is to transfer the meso-scale non-turbulent hydrodynamic model of IFPEN's code, PeliGRIFF, into CORIA's LES code, YALES2, and to extend the current meso-scale modelling to chemical reactions, heat and mass transfers as well as turbulence.
This new simulation tool will be used to study the transfer of understanding and modelling from micro to meso scale (from the PeliGRIFF code to the YALES2 code), as well as to set the foundations of the meso-to-macro transfer (from the YALES2 code to IMFT’s NEPTUNE_CFD code).
The project research work is composed of four technical tasks and organised in two major axis of research :
1. Development of a new massively parallel numerical tool to fill the gap in the complete micro-meso-macro multi-scale analysis
a) Task 1 aims at designing new closure laws for the momentum, heat, and mass fluid/particle transfers based on the micro-scale simulations,
b) Task 2 aims at developing our new massively parallel meso-scale Euler/Lagrange numerical code.
2. Using the new tool to progress on physical comprehension and industrial design
a) Task 3 aims at capitalising our progress into a full multi-scale analysis and to evaluate its validity on well documented test cases,
b) Task 4 aims at applying our new simulation tool developed in Task 2 to two flow configurations representative of small-size industrial applications.

The first validations of the developed models at the mesoscopic scale for the hydrodynamical and thermal transfers have been performed with Yales2 on lab-scale experimental configurations.

At the end of the project, we will have a greater understanding of the coupled phenomena (hydrodynamic, chemical and thermal). Moreover, the capitalization of this knowledge in a CFD code with the ability to perform calculations on massively parallel architectures will enable to apply the models on full-scale industrial problems. Many applications involving turbulent and reactive particulate flows, such as fluid catalytic cracking units, biomass and waste gasification systems, chemical looping combustion, solar receivers could be studied and would lead to a smarter design.

A paper submitted in Proceedings of the Summer Program 2016 (Y. Dufresne et al.), another in the ICPM6 Conference, 2016 (A. Hammouti et al.) and a paper submitted to Int. J of Multiphase Flow (A. Esteghamatian et al.)

Many industrial processes like coal combustion, catalytic craking, gas phase polymerization reactors, and more recently, biomass gasification and chemical looping involve two-phase reactive flows in which the continuous phase is a fluid and the dispersed one comprises rigid particles. Improving both the design and the operating conditions of these processes represents a major scientific and industrial challenge in a context of markedly rising energy cost and sustainable development (MORE control 4 LESS environmental footprint). Thus, it is above all important to better understand the coupling of hydrodynamic, chemical and thermal phenomena in those flows in order to be able to predict them reliably . The aim of MORE4LESS is to build up a multi-scale modelling approach of reactive particulate flows and to focus on the development of what we consider to be the weakest link, i.e. the mesoscopic scale Euler/Lagrange model with heat transfer and chemical reactions for particle-laden flows in dense and dilute regimes. This new modelling will be implemented in a massively parallel numerical code that will enable us to take a step towards the enhanced design of semi-industrial processes.