Turbulent flow over walls and around solid objects

墙壁上和固体物体周围的湍流

• 批准号: 36496-2011
• 负责人: Bergstrom, Donald
• 金额: $ 3.57万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=568738
• 关键词: Turbulent; flow; over; walls; around

The proposed research program uses both numerical and experimental methods to study turbulent flow. Turbulence is the most prevalent flow regime in industrial and environmental applications, and is characterised by enhanced levels of transport for momentum and scalar quantities. Often, turbulent flow involves the presence of a solid surface, which then significantly modifies the turbulence structure and makes the transport characteristics more complex to predict for design purposes. The numerical simulations and experiments being proposed will enhance our fundamental understanding of flows that fit this scenario. The research will be pursued in the context of four specific projects all of which relate to turbulent flow over a solid surface. The first application considers the wake behind a finite cylinder mounted in a boundary layer flow. Of special interest is the complex wake -- or region of disturbed flow -- immediately behind the cylinder. This flow scenario in some ways resembles a short exhaust stack. The second flow considers a plane wall jet over a flat surface, which can be either smooth or covered with surface roughness. The behaviour of the skin friction drag on the wall jet for rough surfaces is not yet well understood. Note that in some ways a finite cylinder resembles a single element of surface roughness. The third flow to be considered is the multiphase flow of a gas or liquid with solid particles. In this case, the solid surface is moving through the fluid, and the solid particles will generate small wakes as well as interact with each other. This flow scenario relates to pneumatic conveyance of granular material as in some agricultural machinery applications and liquid slurry flow in mining applications. The fourth project is the most novel and pertains to flow through a porous tissue scaffold, which is a developing biomedical application. The research program being proposed will be conducted within the fluid dynamics group in Mechanical Engineering at the University of Saskatchewan. It will serve to advance our fundamental understanding and also address some pressing technical challenges being encountered by Canadian industry.

拟议的研究计划使用数值和实验方法来研究湍流。 湍流是工业和环境应用中最普遍的流态，其特征在于动量和标量的传输水平提高。 通常，湍流涉及固体表面的存在，这会显着改变湍流结构，并使传输特性在设计时变得更加复杂。 提出的数值模拟和实验将增强我们对适合这种情况的流动的基本理解。 该研究将在四个具体项目的背景下进行，所有这些项目都与固体表面上的湍流有关。 第一个应用程序考虑了安装在边界层流中的有限圆柱体后面的尾流。 特别令人感兴趣的是复杂的尾流--或扰动流区域--紧接在圆柱体后面。 这种流动情况在某些方面类似于短排气管。 第二种流动考虑了在平坦表面上的平面壁射流，该平坦表面可以是光滑的或覆盖有表面粗糙度。 对于粗糙表面，附壁射流表面摩擦阻力的特性还没有很好的了解。 注意，在某些方面，有限圆柱体类似于表面粗糙度的单个元素。 要考虑的第三种流是气体或液体与固体颗粒的多相流。 在这种情况下，固体表面在流体中移动，固体颗粒将产生小的尾流并相互作用。 该流动场景涉及颗粒材料的气动输送，如在一些农业机械应用中和采矿应用中的液体浆料流动。 第四个项目是最新颖的，涉及通过多孔组织支架的流动，这是一个发展中的生物医学应用。 正在提出的研究计划将在萨斯喀彻温大学机械工程流体动力学组内进行。 它将有助于促进我们的基本理解，并解决加拿大工业面临的一些紧迫的技术挑战。