Bend radius

About: Bend radius is a research topic. Over the lifetime, 3303 publications have been published within this topic receiving 35415 citations. The topic is also known as: minimum bend radius.

Dependence of the critical current of YBa2Cu3O7−δ coated conductors on in-plane bending

Abstract: A new method to measure the effect of in-plane bending on the critical current of YBa2Cu3O7−δ coated conductors is presented. Such a bending mode can be important in transmission cables, saddleback magnets, and double-pancake windings. A linear strain distribution over the width of the conductor develops in this bending mode, where one half of the conductor is under axial compressive strain and the other half is under axial tensile strain. A reversible reduction in critical current of up to 5% is measured in 4 mm wide conductors at a critical bending radius of 0.25–0.28 m. The critical current degrades irreversibly for bending radii less than this because the strain at the edge of the conductor that is under tension irreversibly damages the conductor. The results are described by use of a model that calculates the critical current as a function of in-plane bending radius by taking into account the strain gradient over the width of the sample and the measured dependence of the critical current on axial strain. A similar approach can be used to calculate the degradation of the critical current n of other deformation modes, such as torsion, or other more complex geometries.

Fabrication of flexible thermopile generator

Abstract: A thermoelectric power generation system is developed with a flexible structure. Its micro fabrication has the advantage of miniaturization and integration. Thermoelectric materials are fabricated by using micro fabrication technology. The developed structure is composed of a polyimide sheet as a substrate, thermoelectric materials deposited on the substrate, a heat absorber sheet and a heat sink sheet. The flexibility of this structure depends on the wavy form of the substrate and slits in the substrate, and the heat absorber and heat sink sheets. Because of the characteristic evaluation, open-circuit voltage of 16 µV K−1 per thermocouple was obtained. In addition, the thermopile generator does not break till a bending radius of curvature of 9 mm is reached. A prospect for practical application of the thermoelectric power generator for a curved surface was confirmed.

Device for organizing optical fibers and the like

Abstract: A device for organizing optical fibers and the like at splice or slack points is provided. The device comprises a plurality of stacked tray-like supports having partially turned-up edges, with each separately hinged at one side thereof to a carrier. Each tray-like support is adapted to retain a looped fiber portion without damage by having a width at least equal to twice the minimum bending radius specified for that fiber.

Beam propagation modeling of polarization rotation in deeply etched semiconductor bent waveguides

Abstract: A rigorous study of polarization rotation in deeply etched semiconductor optical waveguide bends has been carried out and results are presented, using the finite element-based fully vectorial beam propagation method. It has been shown that by careful adjustment of the waveguide width, the slant sidewalls and the bending radius, a very compact polarization rotator design, only 60 /spl mu/m long, with extremely low overall loss, and nearly 100% polarization conversion ratio can be achieved.

High-Sensitivity Displacement Sensor Based on a Bent Fiber Mach–Zehnder Interferometer

Abstract: A simple, low-cost, and high-sensitivity optical fiber displacement sensor is presented and fabricated by concatenating two core-offset joints (COJs) with a separation length of 13 mm using a commercial fusion splicer. The two COJs construct an in-line Mach-Zehnder interferometer (MZI). When the MZI is bent to have a bending radius of ~ 17 mm, the interference pattern of the MZI depends strongly on the bending radius. According to this character, we scheme the bent MZI as a displacement sensor in two ways providing two different bending types of the bent MZI. The displacement sensitivities obtained are up to 0.835 and 0.227 nm/μm in the large displacement variation ranges of 350 and 1000 μm, respectively.