Newsletter  2019.3  Index

Theme : "Mechanical Engineering Congress, 2019 Japan (MECJ-19)” Preface Masaaki MOTOZAWA, Hideo MORI Fluid-engineering characteristics of bubbles, and measurement technologies for them Takayuki SAITO (Shizuoka University) Fluid Machinery and Vortical Flow Phenomena Masato FURUKAWA (Kyusyu University) A Case Study of Experimental Fluid Dynamics in a Company (Taking Cavitation Experiments as Examples) Motohiko NOHMI (Ebara Corporation) Flow past two cylinders arranged in tandem within a microbubble plume Tomomi UCHIYAMA, Kotaro TAKAMURE (Nagoya University) Cavitation and dissolved gas: Toward more reliable prediction of cavitation Satoshi WATANABE (Kyusyu University)

 

Flow past two cylinders arranged in tandem within a microbubble plume

Tomomi UCHIYAMA Nagoya University Kotaro TAKAMURE Nagoya University

Abstract

This article is concerned with the investigation of the flow past two cylinders arranged in tandem within a microbubble plume inside a tank. Microbubbles with a mean diameter of 0.05 mm are released by water electrolysis from electrodes placed at the bottom of the tank. Upon rising, these microbubbles induce an upward water flow around them due to buoyancy. Orthogonally to the axis of this microbubble plume, two cylinders with a diameter of 30 mm are arranged in tandem. The bubbles and the water flow around the cylinders are visualized. The experiments reveal the water and bubble shear layers originating at the sides of the lower cylinder, and allow the elucidation of their behavior around the upper cylinder. This article also describes the visualization and simulation of the microbubble plume past a cylinder. The simulation successfully grasps the bubble motion and vortical flow of the water.

Key words

Microbubble plume, Cylinders in tandem, Separated shear layer, Wake

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