Two-phase flow numerical model development based on experimental characterization.

基于实验表征的两相流数值模型开发。

• 批准号: RGPIN-2020-06629
• 负责人: Beguin, Cedric
• 金额: $ 2.7万
• 依托单位: École Polytechnique de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=741342
• 关键词: Two; phase; flow; numerical; model

Two-phase flow numerical model development based on experimental characterization The proposed research program is built to design innovative experiments and develop a theoretical framework for two-phase flows. For industrial applications, the Navier-Stokes equations governing the flows are averaged. This averaging process produces a loss of information on small-scale phenomena. Consequently, modeling these phenomena is required to adequately close numerical models. Our constant concern will be to create experiments to understand and model these small-scale phenomena as the guideline of my research objectives. New developed models will then be implemented in numerical codes based on the averaged Navier-Stokes equations and validated by comparison with large-scale phenomenon experiments. This specific philosophy creates a synergy between numerical and experimental approaches often conducted separately. Three specific objectives support this research vision: a) Model two-phase flow-structure interactions: A first project will study the bubble formation occuring during resin injection for composite manufacturing due to the double scale of the fibre structure. A second project will study the two-phase boundary layer characteristics. Formulating a law of the wall from empirical correlations for two-phase flows would allow numerical predictions at a reasonable cost for complex geometries such as those encountered in the industry and of much better quality than current predictions. b) Determine Particle-particle interactions: A first project will study the phenomenon of coalescence between bubbles inside a two-phase flow, by observing a few bubbles coalescing. The coalescence is part of the balance that governs the bubble sizes and therefore ultimately their trajectories. A second project will measure the turbulence induced by bubbles thanks to innovative technical measurement tools. c) Construct correlation for forces on submerged particles: A first project will numerically assess a bubble rising close to a wall. A second project will study the lift forces of a few particles. If correlations of the force coefficient for isolated particles are relatively well known, their corresponding correlation still requires improvements. A cloud of bubbles placed between a moving bell and a fixed wall will be monitored. A third project will study the drag of a bubble by observing the wake of a rising bubble thanks to 3D PIV. Thus, the research we propose will focus on fundamental experiments to construct an accurate and consistent formulation for dispersed flow simulations. This innovative research will lead to the development of better computational models to shed insight into a variety of two-phase flow problems that affect the welfare of the Canadian population and the competitiveness of the Canadian industry. The lack of reliable two-phase flow numerical procedures prevents breakthrough on the numerous industrial processes using two-phase flow.

基于实验表征的两相流数值模型开发拟议的研究计划旨在设计创新实验并开发两相流的理论框架。对于工业应用，控制流动的Navier-Stokes方程被平均。这种平均化过程造成了小尺度现象的信息损失。因此，需要对这些现象进行建模，以充分关闭数值模型。我们一直关注的是创造实验来理解和模拟这些小规模的现象，作为我的研究目标的指导方针。新开发的模型，然后将实施的数值代码的基础上平均的Navier-Stokes方程和验证与大规模的现象实验比较。这种特定的理念创造了一个协同作用之间的数值和实验方法往往单独进行。三个具体目标支持这一研究愿景：a）模型两相流-结构相互作用：第一个项目将研究由于纤维结构的双重尺度，在树脂注射复合材料制造过程中发生的气泡形成。 第二个项目将研究两相边界层特性。从两相流的经验相关性中制定壁面定律，将允许以合理的成本对复杂几何形状进行数值预测，例如工业中遇到的那些，并且比目前的预测质量好得多。B）确定粒子-粒子相互作用：第一个项目将通过观察一些气泡的聚结来研究两相流中气泡之间的聚结现象。聚结是控制气泡大小的平衡的一部分，因此最终控制它们的轨迹。第二个项目将测量气泡引起的湍流，这要归功于创新的技术测量工具。c）构建浸没颗粒上的力的相关性：第一个项目将对靠近壁面上升的气泡进行数值评估。第二个项目将研究几个粒子的升力。如果孤立粒子的力系数的相关性是相对公知的，它们相应的相关性仍然需要改进。将监测放置在移动钟和固定壁之间的气泡云。第三个项目将通过3D PIV观察上升气泡的尾流来研究气泡的阻力。因此，我们提出的研究将集中在基础实验，以构建一个准确和一致的配方分散流模拟。这项创新研究将导致更好的计算模型的发展，以深入了解各种影响加拿大人口福利和加拿大工业竞争力的两相流问题。由于缺乏可靠的两相流数值计算方法，阻碍了在许多使用两相流的工业过程中取得突破。