Analysis of mixing and mass transport processes in bubble swarms under the influence of bubble-induced turbulence

本计画的目的是研究气泡群中的混合与传质过程，并考虑气泡诱导的紊流效应。高分辨率3D光学测量技术将用于确定潜在的物理过程，以验证现有的质量传输模型并验证项目合作伙伴进行的数值模拟。实验将在第一个资助期内设计和鉴定的定制通道中进行。自由移动颗粒网格和主动湍流网格将用于在宽范围的尺度和强度上调整湍流水平，以模拟真实的气泡诱导的湍流的强度、光谱特性和相干性。对于实验分析，将与项目合作伙伴合作研究化学反应系统。该系统允许通过荧光传感器量化化学反应的选择性。这使得分析湍流对选择性的影响成为可能。这种独特的方法适用于研究一个单一的气泡或群体的气泡在一个现实的湍流的行为。特别是，气泡运动，气泡变形，气泡振动，质量传输到湍流，并由气泡引起的湍流混合过程将使用最先进的，非侵入式三维光学测量技术进行系统研究，并将结果与项目合作伙伴的数值流模拟结果进行分析和比较。

Aim of this project is to investigate the mixing and mass transport processes in bubble swarms taking into account the effect of bubble-induced flow turbulence. High resolution 3D-optical measurement techniques will be applied to determine the underlying physical processes, in order to verify existing mass transport models and to validate numerical simulations carried out by the project partners. The experiments will be conducted in a custom built channel designed and qualified during the first funding periode. Free moving particle grids and active turbulence grids will be used to adapt the turbulence level over a wide range of scales and intensities in order to simulate the intensity, spectral characteristics and coherence of real bubble-induced turbulence. For the experimental analysis a chemical reactive System will be investigated in cooperation with the project partners. This system allows to quantify the selectivity of the chemical reaction by means of fluorescent sensors. This makes it possible to analyze the effect of turbulence on the selectivity. This unique approach is applied to study the behavior of a single bubble or groups of bubbles in a realistic turbulent flow. In particular, bubble motion, bubble deformation, bubble vibration, mass transport into the turbulent flow, and mixing processes caused by the bubble-induced turbulence will be systematically investigated using state-of-the-art, non-intrusive 3D optical measurement techniques and the results will be analyzed and compared with the numerical flow simulation results of the project partners.