In this study, we focus on substance transportation of counter-rotating vortex-pair in the uniform flow, and its interaction with a flat plate is visualized. A water tunnel and aluminum wings (NACA0012) are used to generate a wing-tip vortex pair. Visualization dyes used are fluorescein sodium salt and rhodamine B. The vortex-plate interactions with periodic entrainment are observed when the distance between a plate and vortex-pair are relatively close each other. Experiment and an inviscid vortex dynamics calculation with an Oseen vortex are different when vortex and plate are close, where the effect of a secondary vortex induced by viscosity is important.

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The performance of Knudsen pump which is driven by the thermal induced flow was studied experimentally. In this study, the driven force of the pump system is laminated plates which one surface is black and the other is white. The thermal induced flow is generated by irradiating the infrared lamp to the laminated plates. The system was placed in a grass pipe which was connected to two vessels and irradiated with infrared. It was observed the temperature difference between the black and white surface of the plates was about 10 ℃ and that the pressure ratio of two vessels was about 4%.

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As future space structures, Large Space Structure (LSS) of several kilometers order such as Solar Power Satellite (SPS) is considered. This paper focuses on a mirror reflector for use in SPS of Advanced Model as a large space structure. Towards the first step of a build process by using uniform modules, we assume a structure consisting of a main satellite for attitude control and eighteen mirror panels. There are some patterns in deploying eighteen mirror panels. Due to the difference in deployment patterns, the attitude of a main satellite at the end of deployment will vary. This paper studies four deployment patterns and compares the final attitudes in order to select a desired deployment pattern.

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Some studies consider use of an electrodynamic bare tether system for Jovian capture. Almost of previous studies assumed a spinning tether which was given spin period of 20-40 min from tip mass thrust before close to Jupiter. This paper considers that spacecraft using a non-rotating electrodynamic tether system for de-boost in order to achieve transition from Jovian elliptic orbit to a circular orbit. One reason of using a non-rotating tether is that the tether is perpendicular to Jupiter for longer duration than the case of rotating. Because decelerating force is related to spacecraft's attitude and deceleration section of Jovian circles orbit, orbital parameters and attitude motion should be considered to obtain appropriate attitude change resulting from Lorentz force and torque.

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Erosive burning occurs in solid rocket motors with high-speed internal flow. Large-amplitude velocity-coupled oscillations have sometimes been observed when erosive burning has existed in solid rocket motors. These oscillations have sometimes been caused by the limit cycles of small-amplitude velocity oscillations. In this study, we analyzed the limit cycles by using a linear stability analysis. In order to evaluate the effectiveness of the present analysis, we performed the cold flow tests. These results were compared with our analysis

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Oscillatory combustion has often occurred in hybrid rocket motors. Therefore, it is desired to develop the method to suppress the oscillatory combustion. One of the simple and effective methods is to control the regression rate of hybrid rocket fuels using external radiant heating. In this study, we performed many tests of hybrid rocket motors fueled by paraffin wax and gaseous oxygen in order to obtain the regression rate characteristics with irradiation.

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