Beelen Simon, van Rijsbergen Martijn, Birvalski Miloš, Bloemhof Fedde, Krug Dominik
Physics of Fluids Group, Max Planck Center for Complex Fluid Dynamics, and J.M. Burgers Centre for Fluid Dynamics, University Of Twente, Drienerlolaan 5, 7522 NB Enschede, The Netherlands.
Maritime Research Institute Netherlands, Haagsteeg 2, 6708 PM Wageningen, The Netherlands.
Exp Fluids. 2023;64(2):31. doi: 10.1007/s00348-022-03568-6. Epub 2023 Jan 24.
We report the development of a novel measurement system designed to measure bubble properties in bubble curtains (i.e. planar bubble plumes) in situ alongside acoustical measurements. Our approach is based on electrical, contact-based needle sensors in combination with an optical system. The latter is used for calibration and validation purposes. Correcting for the insensitive distance of the needle tips yields very good agreement between the two approaches in terms of the local void fraction and bubble size distributions. Finally, the system is employed to study bubble plumes evolving from three different hose types. All hoses display consistent self-similar behaviour with spreading rates increasing with increasing gas flow. The spreading is further found to be significantly higher when the bubble plumes originated from a porous hose compared to the two other hose types featuring either discrete holes or nozzle elements.
我们报告了一种新型测量系统的开发，该系统旨在原位测量气泡幕（即平面气泡羽流）中的气泡特性，并同时进行声学测量。我们的方法基于基于电接触的针状传感器与光学系统相结合。后者用于校准和验证目的。校正针尖的不敏感距离后，两种方法在局部空隙率和气泡尺寸分布方面取得了非常好的一致性。最后，该系统用于研究由三种不同软管类型产生的气泡羽流。所有软管都表现出一致的自相似行为，随着气体流量的增加，扩散速率也增加。进一步发现，与具有离散孔或喷嘴元件的其他两种软管类型相比，当气泡羽流源自多孔软管时扩散明显更高。
