In this study, pressure distributions were reconstructed from phase-locked surface deformation measurements on a thin plate. Slope changes on the plate surface were induced by an external flow interacting with the specimen and measured with a highly sensitive deflectometry setup. The Virtual Fields Method (VFM) was used to obtain pressure reconstructions from the processed surface slopes and the plate material constitutive mechanical parameters. The applicability of the approach in combination with phase-locked measurements is demonstrated using a synthetic jet setup generating a periodic flow in air. Phase-averaging slope data allows mitigating random noise effects and resolving low-range differential pressure amplitudes despite the turbulent flow. The size of the spatial structures of the investigated low amplitude flow events identified in full-field with the present method are O ( 1 ) mm $\mathcal {O}(1)~\text {mm}$ , which is beyond the capabilities of other available surface pressure measurement techniques. Challenges and limitations in achieving the metrological performance for resolving the observed surface slopes of O ( 0.1 ) mm km − 1 $\mathcal {O}(0.1)~\text {mm km}^{-1}$ are described and improvements for future applications are discussed.

中文翻译：

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使用虚拟场方法从相位平均偏转测量重建表面压力

在这项研究中，压力分布是根据薄板上的锁相表面变形测量重建的。板表面的斜率变化是由与样品相互作用的外部流动引起的，并使用高度灵敏的偏转仪设置进行测量。虚拟场法 (VFM) 用于从处理过的表面斜率和板材本构机械参数中获得压力重建。使用在空气中产生周期性流动的合成射流装置证明了该方法与锁相测量相结合的适用性。尽管存在湍流，相位平均斜率数据允许减轻随机噪声影响并解决低范围压差幅度。用本方法在全场识别的调查低振幅流动事件的空间结构大小为 O ( 1 ) mm $\mathcal {O}(1)~\text {mm}$ ，这超出了能力范围其他可用的表面压力测量技术。描述了在解决观测到的表面斜率 O ( 0.1 ) mm km − 1 $\mathcal {O}(0.1)~\text {mm km}^{-1}$ 的计量性能方面的挑战和局限性未来的应用进行了讨论。