Abstract Accurate measurement of high-speed flows in the presence of elevated levels of shear and turbulence is a challenging yet necessary endeavor to understand ubiquitous flows that are of great engineering importance. While Eulerian methods, such as Particle Image Velocimetry, represent the traditional approach, Lagrangian alternatives, such as Particle Tracking Velocimetry, have witnessed a resurgence recently due to improved technology and interest in Lagrangian analysis methods. In this research, a recently developed implementation of a volumetric Lagrangian technique for tracking particles in densely seeded flows, namely, Multi-Pulse Shake-The-Box (MP-STB) with the specific implementation referred to as Four-Pulse Shake-The-Box is described and its performance in high-speed jet flows is evaluated. The MP-STB technique is based on recent developments in the Shake-The-Box method by Novara et al. (Experiment in Fluids 60(3):44, 2019) and uses low-speed cameras combined with a double-exposed image acquisition strategy and multi-pulse tracking. Its use of four laser pulses in quick succession with an uneven pulse timing scheme allows for high-accuracy estimates of velocity and acceleration, and repeated ensembles of short-duration, time-resolved measurements in realistic high-speed flows. Experiments with circular jets operating at exit Mach numbers of 0.31 and 0.59 in two different configurations, namely, free jets and jets impinging on a ground plate located 4.75 jet diameters away from the nozzle, were performed to evaluate MP-STB. Scattered four-particle tracks from MP-STB were mapped onto a regular Eulerian grid through the Fine Scale Reconstruction implementation of the VIC# data assimilation method by Jeon et al. (2018). Unique information, including acceleration fields, is presented for these well-known canonical flows. Comparisons with traditional Eulerian measurements from Tomographic PIV, Stereoscopic PIV, and planar PIV are provided to validate the accuracy and comparative cost of volumetric MP-STB measurements combined with the VIC# data assimilation technique. Graphic abstract

中文翻译：

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使用多脉冲振动盒和精细尺度重建 (VIC#) 对高速射流进行拉格朗日和欧拉测量

摘要 在剪切和湍流水平升高的情况下准确测量高速流动是一项具有挑战性但必要的努力，以了解具有重要工程意义的无处不在的流动。虽然欧拉方法（例如粒子图像测速法）代表了传统方法，但由于技术的改进和对拉格朗日分析方法的兴趣，拉格朗日替代方法（例如粒子跟踪测速法）最近又出现了复苏。在这项研究中，最近开发了一种用于跟踪密集种子流中粒子的体积拉格朗日技术的实现，即多脉冲振动盒 (MP-STB)，其具体实施称为四脉冲振动。描述了 Box 并评估了它在高速射流中的性能。MP-STB 技术基于 Novara 等人的 Shake-The-Box 方法的最新发展。（Experiment in Fluids 60(3):44, 2019）并使用低速相机结合双曝光图像采集策略和多脉冲跟踪。它使用快速连续的四个激光脉冲和不均匀的脉冲定时方案，允许对速度和加速度进行高精度估计，并在现实的高速流动中重复进行短时、时间分辨测量的集合。以两种不同的配置，即自由射流和射流撞击位于距喷嘴 4.75 射流直径的底板上的圆形射流，在 0.31 和 0.59 的出口马赫数下进行实验，以评估 MP-STB。来自 MP-STB 的分散四粒子轨迹通过 Jeon 等人的 VIC# 数据同化方法的精细尺度重建实现映射到规则的欧拉网格上。(2018)。为这些众所周知的规范流提供了独特的信息，包括加速度场。提供与来自断层 PIV、立体 PIV 和平面 PIV 的传统欧拉测量值的比较，以验证体积 MP-STB 测量与 VIC# 数据同化技术相结合的准确性和比较成本。图形摘要 提供平面 PIV 以验证体积 MP-STB 测量与 VIC# 数据同化技术相结合的准确性和比较成本。图形摘要 提供平面 PIV 以验证体积 MP-STB 测量与 VIC# 数据同化技术相结合的准确性和比较成本。图形摘要