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A unique solar thermal electric system is proposed and tested in the present study. In this system, an organic working fluid, which is suitable for a temperature range appropriate for solar energy, is adopted. We call this system as "solar organic Rankine cycle system" (SORCS). In order to improve the thermal efficiency by using solar energy, a displacement-type scroll expander and compound parabolic concentrator (CPC) solar collector are used. This system consists of very simple components that are similar to the ones used in an air conditioner and is very cost effective. The present paper reports on the experimental results of the scroll expander unit and the practical operation of the proposed SORCS under actual solar radiation input. The total thermal efficiency of the present SORCS attains 7% (42% when cooling water is used for the cogeneration system).

In this paper ， 丘 h曲 er evaluations of peribrmances of prototype Mg −alloy micro ve 質ical axis wind turbine were conducted ． In addition ， a comparative study of airfbils fbr ve 而 cal wind turbine was conducted ； they are a prototyped airfbil based on the Clark − Y airfbi1 ， a numerically optimized airfbi1 ；NUT airf( )U ， and NACAOO18airfbi1 ， At first ， aerodynamics coe 伍 cients of liR ， drag and momentum centered at

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In this report, numerical analyses of performances of prototype Mg-alloy micro vertical axis wind turbine (VAWT) were conducted. It has three wings with usual NACA0018 wing section. Typical Reynolds number based on the wind speed and the wing chord length were set around 3.3×10 4 with consideration of use as a portable-type micro VAWT system for engineering educations. In such low Reynolds number cases, somewhat different way of design would be required because of flow separation and reattachment, short bubbles etc. We also examined a torque variation generated from the wings using 3-D unsteady CFD analysis and compared the results and flow patterns for higher performance.