Daido University

About: Daido University is a education organization based out in Nagoya, Japan. It is known for research contribution in the topics: Ultimate tensile strength & Proton exchange membrane fuel cell. The organization has 209 authors who have published 423 publications receiving 3223 citations.

Internal strain measurement for Nb3Sn wires using synchrotron radiation

Abstract: The internal strain of the practical Nb3Sn wires under tensile strain were measured by synchrotron radiation. The x-ray energy of 72 keV was selected to obtain the diffraction from the Nb3Sn in the composite wire. The axial and lateral strains of the as-reacted and prebent wire were investigated. The Nb3Sn 321 and 320 diffraction peaks were measured to obtain accurate strain data because of their high intensity. It was found that the relationship between internal and external strain under the tensile strain is slightly different. The strain of the Nb3Sn 321 plane reveals the similar total strain applied to the Nb3Sn wire. The ratio of lateral/axial strain for the as-reacted and prebent wires is 0.34 and 0.30, respectively.

Control of leading edge separation on airfoil using DBD plasma actuator with signal amplitude modulation

Abstract: In this study, the separation control of an airfoil when a dielectric barrier discharge (DBD) plasma actuator is mounted on its leading edge was examined. Experiments were performed at a Reynolds number of approximately 67,000 with an external airflow of 10 m/s. The DBD plasma actuator was installed on an NACA 0015 airfoil with a 100 mm chord and 150 mm width at x/c = 0.025, where x was the vertical distance measured from the leading edge and c was the chord length. Lift force measurements, flow visualization and velocity measurements were conducted to investigate the performance of the DBD plasma actuator, which was driven by either pulse modulation with amplitude modulation (PM + AM) or pulse modulation only (PM). The PM + AM case was designed to consume the same amount of power as the PM case. The result showed that the PM + AM case improved the lift coefficient compared to the PM case for both St = 0.6 and St = 4.0. Under the stall control condition (angle of attack, α = 16°) and high angle of attack condition (α = 18°), the PM + AM case always demonstrated improved lift over the PM case; the improvement in lift was greater at α = 18° than at α = 16°. Flow visualization confirmed larger and stronger vortex shedding for the PM + AM case over the PM case.

Influence of a plasma-treated nutrient solution containing 2,4-dichlorobenzoic acid on the growth of cucumber in a hydroponic system

Abstract: Allelochemicals are organic compounds exuded from the roots of plants, which have autotoxic effects on plant growth. In this study, the decomposition of 2,4-dichlorobenzoic acid (DCBA), an allelochemical of cucumber, by plasma generated in an air bubble in solution is examined, and the influence of plasma treatment of the solution on cucumber growth in a hydroponics system is investigated. Air gas is injected into water through a vertically positioned glass tube, into which a high-voltage wire electrode is placed to generate plasma. The concentration of DCBA decreases and the concentration of chloride ion produced by the dichlorination of DCBA increases with increasing discharge treatment time. Consequently, most DCBA has decomposed after 24 h of treatment. The discharge-treated solution is used as a nutrient solution for cultivating cucumber plants in a rockwool hydroponic system. The results show that the growth of most plants is inhibited by adding DCBA, as well as by the decrease in pH during discharge treatment; in contrast, plants subjected to discharge treatment with pH adjustment grow healthily.