2013 Fiscal Year Final Research Report

Development of Doppler Global Velocimetry using a DPSS laser

Research Project

Project/Area Number	23560198
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Fluid engineering
Research Institution	Nagasaki University
Principal Investigator	SAKAGUCHI Daisaku 長崎大学, 工学(系)研究科(研究院), 准教授 (70244035)
Project Period (FY)	2011 – 2013
Keywords	レーザー / ドップラー効果 / 流体計測
Research Abstract	DGV (Doppler Global Velocimetry) with a DPSS (Diode-Pump Solid State) laser is successfully developed in this research. DGV is a system to measure velocity of particles crossing a laser sheet, by analizing the scattered doppler shifted frequency of a light sheet. The light frequency shift is very weak because of the very low speed of the particles compared to the speed of light. In order to overcome this problem, an absorption line of the molecular iodine was used. The frequency shift as a function of the absorption line of the iodine cell can be traced back to particle velocity. The optical setup with the DPSS laser and the iodine cell was developed in this research and measurement accuracy of the velocity field from the rotating disc was confirmed. It is found that the DPSS laser is suitable laser source for DGV system because of its high stability and narrow line width, as a result, high measurement accuracy is obtained by this system.