Developing three-dimensional qualitative visualization method for supersonic jets flow field using rainbow schlieren computed tomography

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K05805
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Fluid engineering
• Research Institution: The University of Kitakyushu
• Principal Investigator: Nakao Shinichiro 北九州市立大学, 国際環境工学部, 准教授 (40331029)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 超音速 / 定量化 / 可視化 / 衝撃波 / シュリーレン / 噴流 / 3次元

Outline of Final Research Achievements

The rainbow schlieren deflectometry is combined with the computed tomography to obtain three-dimensional density fields of a shock-containing free jet issued from a Laval nozzle(1mm*1ｍｍ). Experiments have been performed at a nozzle operating pressure of where the nozzle is operated at a slightly underexpanded condition. Multidirectional rainbow schlieren pictures of the jet can be acquired by rotating the nozzle about its longitudinal axis in equal angular intervals and the three-dimensional density fields are reconstructed by two types of image analyses for experimental data It is found that excellent quantitative agreement is reached between the jet three-dimensional density fields reconstructed from both the algorithms. The present rainbow schlieren technique is found to be significantly effective to examine a fine shock-cell structure of the shock-containing jet and makes it possible to provide experimental data with high accuracy and reliability on the jet density field.

Free Research Field

圧縮性流体工学