Collaborative Research: Physically-Based Models and System Analysis Tools for Feedback Fluid Flow Control

合作研究：用于反馈流体流量控制的基于物理的模型和系统分析工具

• 批准号: 0523957
• 负责人: Zvi Rusak
• 金额: $ 12万
• 依托单位: Rensselaer Polytechnic Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0523957&HistoricalAwards=false
• 关键词: Collaborative; Research; Physically; Based; Models

The research objective is to develop a generic theory for model based feedback flow control. Accessiblemodels, design and analysis methods and, indeed, clearer understanding of fluidic temporal actuation andsystem parameters influence of flow system behavior, as characterized by the onset or suppress of variousinstabilities, are the key components. This integrated theoretical and numerical research programcombines unique fluid flow modeling expertise at Rensselaer Polytechnic Institute (RPI) and systemanalysis and control theory capabilities at Northeastern University (NEU). We envisage a closelycoupled,well-coordinated synergy between the two institutions and with an already existing collaborativeteam in industry and academe. A set of case studies of increased complexity will be used to isolate keystumbling blocks and develop critical enablers. Well beyond these benchmarks, effective feedback flowcontrol will provide critical enablers for substantial improvements in a wide range of applications,ranging from aircraft, automotive, semiconductor, imaging, air conditioning, the chemical processindustry, bio-reactors, furnaces, to aeroengines & ground-based gas turbines for power generation.The defining challenge in this nascent field arises from the deep chasm between the intrinsic complexityof unsteady and transient actuated fluid dynamics and the simplicity and robustness required of modelsuseful for feedback design and analysis, and architecture (i.e., sensors and actuators placement andspecifications) optimization. Addressing this challenge, the proposal is characterized by an analytic,physics-based approach and aims at the fundamentals of fluid dynamics in relation to actuation. Essentialnew modeling tools will be developed to efficiently characterized targeted dynamic manifolds, matchedby controller and observer design and architecture optimization tools, geared to respect - and exploit - theexceptionally limited validity envelopes of such models. The selected benchmarks, characterized bysignificant unsteady motion and transient dynamics, include separation and stall of airfoils, the stability ofthe backward-facing step flow, the separated vortical wake flow behind a bluff body, the stability ofshock waves over airfoils, and the transition to breakdown states in a swirling flow in a pipe. Each isimportant in its own right for both fundamental science and critical applications. More significantly, theyhighlight and isolated key technical issues in a framework which is both tractable and sufficiently rich.Intellectual Merit. Dominant techniques in the emerging field of feedback flow control such as transferand describing functions and empirical (POD) Galerkin modes are often limited to nearly linear systemsor tend to exhibit very poor capability to capture transient dynamics and actuation, and to sustainparametric changes in the operating point. The need for new tools, fresh and innovative approaches in thisfield, and indeed the very evolution of feedback flow control as a new and well defined discipline, are anoutgrowth of these gaps. The main thrust of the research will be to develop means to address theseshortcomings by an appeal to the fundamental physics of the problems, combined with a systemtheoretical approach. We look to develop reduced-order models which are derived from the Navier-Stokesequation and phenomenological physical characteristics, such as energy production, absorption andtransfer, and natural instabilities, and account for realistic boundary conditions and meaningful actuationtechniques. The research will be characterized by tight coupling of the PIs knowledge bases in systemtheory and fluid dynamics and leverage prolific ongoing interactions with a cross disciplinary group ofexperts in numerical flow simulations and imaging, experimentalists, and industrial researchers; this rangeof expertise is imperative, and external collaborations will serve as a source of initial insight, an impetusfor new directions, and an ongoing resource and for validation of developed tools and understanding.Broad Impact. The proposed approach is unique in its synergistic use of classical and modernmathematical tools, fluid dynamics and control techniques to provide a comprehensive theory of feedbackflow control, led by a collaboration between two experts in these areas. The project will lead to animproved understanding of the mechanisms that provoke instabilities and transition phenomena in variousflow systems, the ways to actively control them for improved performance, and will provide rigorousmeans to explore and define the yet unclear feasibility scope of feedback control in fluid flow systems.These advances will impact both on the basic science and on a wide range of industrial applicationsinvolving fluid flow / aerodynamics, shear layer mixing and combustion. It will also contribute tononlinear control theory, developing new design and analysis methods for a challenging class of systems.

研究的目的是发展一个通用的理论模型为基础的反馈流量控制。可扩展的模型、设计和分析方法以及对流体瞬时驱动和系统参数对流动系统行为的影响的更清楚的理解是关键组成部分，这些流动系统行为的特征在于各种不稳定性的发生或抑制。这个综合的理论和数值研究计划结合了伦斯勒理工学院（RPI）独特的流体流动建模专业知识和东北大学（NEU）的系统分析和控制理论能力。我们设想这两个机构之间以及与工业界和企业界现有的合作团队之间形成一种密切耦合、协调良好的协同效应。将使用一组复杂性增加的案例研究来隔离关键代码块并开发关键的使能器。远远超出这些基准，有效的反馈流量控制将提供关键的推动力，在一个广泛的应用，从飞机，汽车，半导体，成像，空调，化学加工工业，生物反应器，熔炉，航空发动机地面大幅改善&。在这个新兴领域的决定性挑战来自于不稳定和不稳定的内在复杂性之间的深刻鸿沟。瞬态致动流体动力学和用于反馈设计和分析的模型所需的简单性和鲁棒性，以及体系结构（即，传感器和致动器布置和规格）优化。为了应对这一挑战，该提案的特点是采用分析性的、基于物理的方法，并着眼于与驱动有关的流体动力学的基本原理。将开发大量新的建模工具，以有效地表征目标动态流形，与控制器和观测器设计和架构优化工具相匹配，以尊重和利用这些模型的异常有限的有效性包络。所选的基准包括翼型的分离和失速、后台阶流的稳定性、海崖体后的分离涡尾流、翼型上激波的稳定性以及管内旋流向破裂状态的转变，这些基准具有显著的非定常运动和瞬态动力学特征。每一个都对基础科学和关键应用都很重要。更重要的是，他们在一个既易于处理又足够丰富的框架中突出和隔离关键技术问题。在新兴的反馈流控制领域中的主导技术，如传递和描述函数和经验（POD）Galerkin模式，通常限于接近线性的系统，或往往表现出非常差的捕获瞬态动力学和致动的能力，以及维持工作点的参数变化。在这个领域需要新的工具，新的和创新的方法，实际上反馈流控制作为一个新的和定义良好的学科的发展，是这些差距的结果。这项研究的主旨将是通过呼吁问题的基本物理学，结合系统理论方法，开发解决这些短缺的方法。我们希望开发降阶模型，这些模型来自Navier-Stokes方程和唯象物理特性，如能量产生，吸收和转移，以及自然不稳定性，并考虑现实的边界条件和有意义的actuationtechniques。该研究的特点是系统理论和流体动力学的PI知识库的紧密耦合，并利用与数值流模拟和成像，实验人员和工业研究人员的跨学科专家组的多产持续互动;这一系列的专业知识是必不可少的，外部合作将成为最初洞察力的源泉，新方向的推动力，和一个持续的资源，并用于验证开发的工具和理解。广泛的影响。所提出的方法是独特的，在其协同使用的经典和现代的数学工具，流体动力学和控制技术，以提供一个全面的理论feedbackflow控制，由两位专家在这些领域的合作。该项目将导致更好地理解在各种流动系统中引起不稳定性和过渡现象的机制，积极控制它们以提高性能的方法，这些进展将对基础科学和涉及流体流动/空气动力学的广泛工业应用产生影响，剪切层混合和燃烧。它还将有助于非线性控制理论，为一类具有挑战性的系统开发新的设计和分析方法。