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

流动从确定性层流状态过渡到随机湍流状态的过程在智力上具有挑战性，在技术上也很重要，注意到表面摩擦，表面传热和声发射的水平在过渡之前，期间和之后都有明显的不同。我们的研究计划集中在发现层流到湍流过渡机制的基本规范流以及应用航空工程系统的统一主题。典型的过渡流包括Blasius边界层的自然和旁路过渡（大多数人都知道），以及百年未解决的Osborne Reynolds管过渡，而应用的航空过渡流可以在涡轮定子转子级中找到，它形成了喷气发动机推进系统的构建块。我们希望通过专注于两个方面来建立一个高度创新和有影响力的研究计划：确定国际流体研究界普遍和深刻兴趣的主要前沿，未解决的问题;开发和使用高度准确，经过彻底验证的最先进的调查方法，即超大规模，物理现实，空间发展直接数值模拟（DNS）。

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).