Tatsuro Inage

Interferometric Measurement in Shock Tube Experiments

This chapter describes applications of interferometry to the shock tube experiments. The first topic is Laser Interferometric Computed Tomography (LICT) technique to realize the three-dimensional (3D) density measurement of high-speed and unsteady flow field behind shock waves discharging from nozzles. The second topic is measurement of propagating shock wave in micro-scale shock tube by interferometic approach. Micro-scale shock tube is being researched in several fields of science recently and micro-scale shock wave has possibilities of applications for various fields medical, engineering, ...etc. Clarifying the characteristics of micro-scale shock tube to generate the micro-scale shock wave is very important step for the application.

Improvement of a Diaphragmless Driver Section for a Small Diameter Shock Tube

Recently, the micro-shock waves have attracted attention of researchers in several fields of science. It is well known that the shear stress and the heat transfer between a test gas and a wall lead to significant deviations from the normal theory of a shock wave propagating in a small diameter shock tube[1][2]. In our previous research, we developed a diaphragmless driver section using a rubber valve, and estimated the valve opening characteristics[3].

Preliminary Experiment of the Drag Force Measurement by Using Strain Gauge in the Hypersonic Flow

Recently, the space development project and the development of the hypersonic aircraft become more active in the world. In Japan the development facilities which compare favorably with the aerospace developing countries are needed.

Quantitative Density Measurement of the Interaction Field of Side Jet and Cross Flow by Colored-Grid Background Oriented Schlieren (CGBOS) Technique

The Background Oriented Schlieren (BOS) technique proposed by Meier [1] enables us to take a quantitative density measurement of a flow field with computeraided image analysis. In the past several years, the BOS technique has been applied in various experiments [2],[3].

Hybrid algebraic reconstruction technique for tomographic reconstruction of the wave interaction around a rectangular rod

Laser Interferometric Computed Tomography (LICT) measurement enabled observation of the three-dimensional (3-D) density distribution of the unsteady flow field quantitatively. The interferometric fringe images are used as the projection data, and the flow field is reconstructed by appropriate reconstruction technique in LICT measurement. The flow field which do not include any object is reconstructed clearly. On the other hand, if the obstacle is included in the flow field, laser beam cannot pass through the obstacle and the projection data have imperfect parts. These imperfect parts cause strong artifacts in the CT images and we cannot identify any unsteady phenomena. To reduce these artifacts, we applied Hybrid Algebraic Reconstruction Technique (HART). In this study, the HART technique will be applied to the problem of reconstruction of wave interaction around a rectangular rod, and CT images obtained using HART and Algebraic Reconstruction Technique (ART) will be compared.Graphical Abstract

Three-dimensional interferometric CT measurement of discharging shock/vortex flow around a cylindrical solid body

To elucidate the dynamics of heat and fluid flows, three-dimensional aspects of the fields are of great significance. In the research of high-speed flow field including shock waves the common flow visualization methods are shadowgraph, color-schlieren, and interferometric methods. In these methods the three-dimensional (3-D) density information is integrated along an optical observation axis and go down to two-dimensional (2-D) in the represented image. The 3-D measurement of the complicated flow field including various phenomena has not been developed especially in high speed gasdynamic research. Experimental data are in the poor situation.