In this study, the year-round hydrogen balance and the heat input required for temperature control of this air heat exchanged hydrogen storage alloy system are simulated for an independent electric power utilization system using photovoltaic power generation with hydrogen energy storage system assuming arbitrary regions and electric power demand patterns in Japan. As a new method for controlling alloy’s temperature, the authors have developed the air heat exchanged hydrogen storage alloy system that is supplying an air temperature for hydrogen storage alloy. Since hydrogen storage alloy’s characteristics of absorption and desorption heavily depends on operating temperature, temperature control is one of the critical issues in the design of the hydrogen storage alloy system. While there are several hydrogen storage methods, hydrogen storage alloy is one of the most suitable methods for stationary hydrogen storage. In recent years, hydrogen has been attracting attention as a long-term energy storage that can absorb fluctuations of the output of variable renewable energy sources. Therefore, it is possible to change the flow characteristics and vortical structures of the rectangular jet by adding tapered triangular tubes with different angles. However, the overall spread of the jet is almost the same as that without the tapered triangle tubes due to the diffusion of the jet along the nozzle span length. On the other hand, in the case of the jet with convergent tapered triangular tubes with α = −6°, the jet maintains a relatively rectangular jet shape upstream due to the local increase in vorticity on the long side of the nozzle and the increase in turbulent kinetic energy along the nozzle shape. As a result, the jet becomes a circular jet shape until relatively downstream, and the jet spread was smaller than that of the other jets. In the case of jet with divergent tapered triangular tubes with α = +6°, the local vorticity and turbulent kinetic energy increase at the corners of the jet were suppressed and the profile followed the jet shape. The spread of the jet is larger than that of other jets. In the case of the jet without tapered triangular tubes, the three–dimensional deformation of the vortex ring produces strong positive and negative vorticity around each axis and also increases the turbulent kinetic energy at the jet corners. The Reynolds number Re (= U 0 H/ ν ν, kinematic viscosity of air) of the jet was 9,000. The mean bulk velocity U 0 from the nozzle exit was about 4.5 m/s. The angles of tapered triangular tubes were changed α = +6° and −6°. The purpose of this study is to clarify the effect of the tapered triangular tubes added to the four corners of a 2:1 rectangular nozzle on the flow characteristics and vortical structures of a rectangular jet. It was found that the anisotropy of deflection also became smaller at the inclination angle of the trapezoidal patterns at which the deflection of the panel became minimal. Moreover, the anisotropy of deflection of the sandwich panel, which is the difference in the deflection depending on the selected two sides of the panel when the relative two sides are fixed and loaded, was investigated. It was found that these synergistic effects cause the minimal inclination angle occur. On the other hand, the shear stress developed in the plates and the core increased with decrease in the inclination angle, which had the effect of reducing the deflection of the sandwich panel. The deflection of the corrugated core itself increased with decrease in the inclination angle of the trapezoidal patterns. It was found that there is an inclination angle of the patterns at which the deflection of the sandwich panel becomes minimal. The analysis was performed by changing the inclination angle of the trapezoidal patterns of the core. The deflection always became maximum at the center of the panel. The four sides of the sandwich panel were rigidly fixed, and a uniformly distributed load was applied to the surface of the top plate. The models for finite element method were created by taking into account the geometrical limitations of the corrugated core due to the space between both plates and the manufacturing condition. The size of the top and bottom plates were 200 mm square, and the height of the sandwich panel was fixed at 13.6 mm. This paper reports the deflection behavior of the sandwich panel with corrugated core of trapezoidal cross section.
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