Enhancement of flow measurements using fluid-dynamic constraints

JOURNAL OF COMPUTATIONAL PHYSICS

卷:344

Article

Egger, H.¹  Seitz, T.¹  Tropea, C.² 

[1] Tech Univ Darmstadt, Inst Numer Anal & Sci Comp, Dept Math, Darmstadt, Germany

[2] Tech Univ Darmstadt, Inst Fluid Mech & Aerodynam, Ctr Smart Interfaces, Darmstadt, Germany

关键词: Velocity measurements;    Denoising;    Optimal control with pdes;    Fluid dynamics;    Navier-Stokes equations;    Inverse problems;    Regularization;   

DOI  :  10.1016/j.jcp.2017.04.080

来源: Elsevier

【 摘 要 】

Novel experimental modalities acquire spatially resolved velocity measurements for steady state and transient flows which are of interest for engineering and biological applications. One of the drawbacks of such high resolution velocity data is their susceptibility to measurement errors. In this paper, we propose a novel filtering strategy that allows enhancement of the noisy measurements to obtain reconstruction of smooth divergence free velocity and corresponding pressure fields which together approximately comply to a prescribed flow model. The main step in our approach consists of the appropriate use of the velocity measurements in the design of a linearized flow model which can be shown to be well-posed and consistent with the true velocity and pressure fields up to measurement and modeling errors. The reconstruction procedure is then formulated as an optimal control problem for this linearized flow model. The resulting filter has analyzable smoothing and approximation properties. We briefly discuss the discretization of the approach by finite element methods and comment on the efficient solution by iterative methods. The capability of the proposed filter to significantly reduce data noise is demonstrated by numerical tests including the application to experimental data. In addition, we compare with other methods like smoothing and solenoidal filtering. (C) 2017 Elsevier Inc. All rights reserved.

【 授权许可】

Free