Discovering the Transition Mechanisms in Fundamental Canonical Flows and in Idealized Propulsion Component Systems

发现基本规范流和理想化推进组件系统中的过渡机制

• 批准号: RGPIN-2016-03619
• 负责人: Wu, Xiaohua
• 金额: $ 2.77万
• 依托单位: Royal Military College of Canada
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=638916
• 关键词: Discovering; Transition; Mechanisms; Fundamental; Canonical

The processes of flow transitioning from a deterministic laminar state to a stochastic turbulent one are both intellectually challenging and technologically important, noting that the levels of skin-friction, surface heat transfer and sound emission are all markedly different before, during and after the transition. Our research program centers on the unifying theme of discovering laminar-to-turbulent transition mechanisms in fundamental canonical flows as well as in applied aeronautical engineering systems. Canonical transitional flows include the Blasius boundary layer’s natural and bypass transition (mostly understood), and the century-old unresolved Osborne Reynolds pipe transition, whereas applied aeronautical transitional flows can be found in a turbomachinery stator-rotor stage, which forms the building block of jet engine propulsion system. We aspire to building a highly innovative and impactful research program by focusing on two aspects: identify major cutting-edge, unresolved problems that are of general and profound interest to the international fluids research community; develop and use highly accurate, thoroughly validated, state-of-the-art investigative approach, namely, very-large-scale, physically-realistic, spatially-developing direct numerical simulation (DNS).

流动从确定性层流状态到随机湍流状态的转变过程在理论上具有挑战性，在技术上也具有重要意义，指出在转变之前、过程中和转变后，表面摩擦、表面换热和声发射的水平都有明显的不同。我们的研究计划集中在一个统一的主题上，即在基本正则流和应用航空工程系统中发现层流到湍流的转变机制。典型的过渡流包括Blasius边界层的自然和旁路过渡(大部分已被了解)，以及百年未解决的Osborne Reynolds管过渡，而航空应用过渡流可以在叶轮机械的定子-转子级中找到，这构成了喷气发动机推进系统的基石。我们致力于建立一个高度创新和有影响力的研究计划，专注于两个方面：确定国际流体研究界普遍和深刻感兴趣的重大前沿、悬而未决的问题；开发和使用高精度、充分验证的最先进的研究方法，即超大规模、物理逼真、空间发展的直接数值模拟(DNS)。