| 日時： |
2005年10月12日（水） 10:30〜12:00 |
| 場所： |
京都大学 工学部物理系校舎 2階 213会議室 |
| 講演者： |
Dr. Richard John Brown (Senior Lecturer, School of Engineering Systems, Queensland University of Technology, Australia) |
| 講演題目： |
Recent research on environmental fluid mechanics at the Queensland University of Technology |
| 講演要旨： |
An overview of environmental fluid mechanics research at QUT will be given. Major current projects include:
- Field study of small scale mixing and dispersion (including effect of navigation) in a natural watercourse using a fast response concentration probe,
- Flow field measurement, analysis and visualisation of storm water pollutant removal devices,
- Laboratory study of velocity and scalar field downstream of a propeller.
Recently in Australia there has been considerable concern regarding the transport of pollutants in the water environment. The current research addresses these issues.
|
Field study of small scale mixing and dispersion (including effect of navigation) in a natural watercourse using a fast response concentration probe
Following the successful use of a fast response concentration probe in the laboratory, its use has been extended to the field to relate laboratory experiments to the real world situation. This study focuses on the region close to the point of release. In this region, highly concentrated organic dye is mixed with uncontaminated water (ie, with no dye). Initial concentration spatial gradients (dC/dx) are high. Probability density functions of the scalar are obtained. Effects from navigation (outboard motors) can clearly be seen. It is evident that the mixing process is rapid in the initial stages of release and comparison with typical dispersion modelling methods shows that these methods may not work well close to the point of release of pollutants. |
Flow field measurement, analysis and visualisation of storm water pollutant removal devices
An acoustic Doppler anemometer has been used to map the flow field in this device and a 3D visualisation has been developed. Integration of transverse slices through the flow reveals significant recirculation which significantly effects the performance of the device. |
Laboratory study of velocity and scalar field downstream of a propeller
An experimental study of the velocity and concentration (scalar) fields of a propeller is presented. Field and laboratory measurements were undertaken. The former were up to 50 diameters downstream. Important findings were that the mean velocity and scalar fields quickly become Gaussian while further downstream they both become irregular sometimes approaching approximately linear profiles. Propeller turbulence causes rapid mixing giving an initial concentration dilution factor of 1/20,000 after fifty propeller diameters. Some preliminary comparisons with field measurements of an actual boat in a natural waterway are made. Considerably more work is needed to gain a full understanding of the complex problem of propeller mixing. |
Copyright (C) 2005 Kyoto University. All rights reserved
