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Yves Mercadier

Bio: Yves Mercadier is an academic researcher from Université de Sherbrooke. The author has contributed to research in topics: Supersonic speed & Reynolds stress. The author has an hindex of 7, co-authored 16 publications receiving 569 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the performance of six well-known turbulence models for the study of supersonic ejectors was evaluated and the results showed that the k-omega-sst model agrees best with experiments.

323 citations

Journal ArticleDOI
TL;DR: In this article, numerical results of a supersonic ejector for refrigeration applications are presented, which is based on the NIST-this articlePROP database for refrigerants properties calculations.

163 citations

Journal ArticleDOI
TL;DR: In this article, a two-temperature model for compressible plasma flows is presented, with slightly supersonic conditions with thermal and chemical non-equilibrium, and the flow dynamics results are analysed with different turbulence models and appear to be consistent with results previously published by the authors.
Abstract: This paper presents a two-temperature model for compressible plasma flows. This study concentrates on the behaviour of the plasma jet in the expansion region. The conditions used correspond to the conditions of low-pressure plasma spraying, with slightly supersonic conditions with thermal and chemical non-equilibrium. The flow dynamics results are analysed with different turbulence models and appear to be consistent with results previously published by the authors [3] on the dynamics of low-temperature air jets and favour the Reynolds stress turbulence model. Chemical as well as thermal non-equilibrium are studied.

35 citations

Journal ArticleDOI
TL;DR: In this paper, a mathematical model for the prediction of the thermal behavior of the rotary heat and mass exchanger is presented, which is validated with experimental data and employed to conduct a parametric study.

29 citations

Journal ArticleDOI
TL;DR: In this article, a fully elliptic Navier-Stokes equation solver in conjunction with a Reynolds stress model is validated for mildly and strongly underexpanded jets, and good agreement has been found compared to available measurements for the shock reflections.
Abstract: A fully elliptic Navier-Stokes equation solver in conjunction with a Reynolds stress model is validated for mildly and strongly underexpanded jets. For mildly underexpanded jets, good agreement has been found compared to available measurements for the shock reflections. The model even demonstrated some improvements over a three-dimensional modified κ-e model for turbulent predictions, which confirms the inadequacy of isotropic eddy-viscosity-based models to represent properly the turbulence in those flows. For the strongly underexpanded case, the predicted Mach disk location and size are found to be in excellent agreement compared to available measurements. In addition, the predicted flow structure beyond the disk agrees with experimental observations. An attempt is also made to explain the strong coupling between some dynamic features and heat transfer aspects.

24 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors discuss the fundamentals involved in developing a CFD solution and provide a state-of-the-art review on various CFD applications in the food industry such as ventilation, drying, sterilisation, refrigeration, cold display and storage, and mixing.
Abstract: Computational fluid dynamics (CFD) is a powerful numerical tool that is becoming widely used to simulate many processes in the food industry. Recent progression in computing efficacy coupled with reduced costs of CFD software packages has advanced CFD as a viable technique to provide effective and efficient design solutions. This paper discusses the fundamentals involved in developing a CFD solution. It also provides a state-of-the-art review on various CFD applications in the food industry such as ventilation, drying, sterilisation, refrigeration, cold display and storage, and mixing and elucidates the physical models most commonly used in these applications. The challenges faced by modellers using CFD in the food industry are also discussed.

392 citations

Journal ArticleDOI
TL;DR: In this paper, a comprehensive literature review on ejector refrigeration systems and working fluids is presented, which deeply analyzes ejector technology and behavior, refrigerant properties and their influence over ejector performance.
Abstract: The increasing need for thermal comfort has led to a rapid increase in the use of cooling systems and, consequently, electricity demand for air-conditioning systems in buildings. Heat-driven ejector refrigeration systems appear to be a promising alternative to the traditional compressor-based refrigeration technologies for energy consumption reduction. This paper presents a comprehensive literature review on ejector refrigeration systems and working fluids. It deeply analyzes ejector technology and behavior, refrigerant properties and their influence over ejector performance and all of the ejector refrigeration technologies, with a focus on past, present and future trends. The review is structured in four parts. In the first part, ejector technology is described. In the second part, a detailed description of the refrigerant properties and their influence over ejector performance is presented. In the third part, a review focused on the main jet refrigeration cycles is proposed, and the ejector refrigeration systems are reported and categorized. Finally, an overview over all ejector technologies, the relationship among the working fluids and the ejector performance, with a focus on past, present and future trends, is presented.

359 citations

Journal ArticleDOI
TL;DR: The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results and the relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.
Abstract: The results of detailed experiments and finite element modeling of metal micro-droplet motion associated with metal additive manufacturing (AM) processes are presented. Ultra high speed imaging of melt pool dynamics reveals that the dominant mechanism leading to micro-droplet ejection in a laser powder bed fusion AM is not from laser induced recoil pressure as is widely believed and found in laser welding processes, but rather from vapor driven entrainment of micro-particles by an ambient gas flow. The physics of droplet ejection under strong evaporative flow is described using simulations of the laser powder bed interactions to elucidate the experimental results. Hydrodynamic drag analysis is used to augment the single phase flow model and explain the entrainment phenomenon for 316 L stainless steel and Ti-6Al-4V powder layers. The relevance of vapor driven entrainment of metal micro-particles to similar fluid dynamic studies in other fields of science will be discussed.

333 citations

Journal ArticleDOI
TL;DR: In this paper, the performance of six well-known turbulence models for the study of supersonic ejectors was evaluated and the results showed that the k-omega-sst model agrees best with experiments.

323 citations

Journal ArticleDOI
TL;DR: In this paper, a double approach to thermal plasmas is presented, which combines the scientific procedure with an engineering point of view, and the model is useful in each case for studying important phenomena or processes in greater detail.
Abstract: Electrical arcs and, more generally thermal plasmas, are widely used in many applications and the understanding or the improvement of the corresponding processes or systems, often requires precise modelling of the plasma. We present, here, a double approach to thermal plasma modelling, which combines the scientific procedure with an engineering point of view. First, we present the fundamental properties of thermal plasmas that are required in the models, followed by the basic equations and structures of the models. The third part is devoted to test cases, and its objectives are the study of some basic phenomena to show their influence on arc behaviour in simple configurations, and the validation of the models: we point out the roles of radiation, thermal conductivity and electrical conductivity for a stationary or transient wall-stabilized arc and we validate a three-dimensional model for a free-burning arc.Sections 4–6 deal with several industrial configurations and the model is useful in each case for studying important phenomena or processes in greater detail. For transferred arcs, such as those used in metallurgy, the energy transfer from the arc to the anode, and the presence of metallic vapour and pumping gas are essential. For a non-transferred plasma torch used for plasma spraying, we illustrate the relevance of a three-dimensional model and we present the interaction of the plasma with powders. Problems related to high- and low-voltage circuit-breakers are then presented, and various typical mechanisms are modelled. Finally, several non-equilibrium models useful for quasi-thermal conditions are presented in detail, showing how they take into account the chemical kinetics and two-temperature plasmas occurring under particular conditions, such as decaying arcs or inductively coupled plasmas.

310 citations