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.

Influence of channel aspect ratio and curvature on flow, secondary circulation, and bed shear stress in a rectangular channel bend.

Abstract: Flow within an alluvial channel bend is significantly affected by channel geometry, including curvature ratio (bend radius/channel width, R/B) and aspect ratio (channel width/flow depth, B/H). High curvature bends (R/B≤3) can experience substantially more erosion than milder curvature bends. This study employs a three-dimensional Reynolds-Averaged Navier-Stokes (RANS) model to investigate the effects of curvature ratio and aspect ratio on bend flow with respect to a high curvature (R/B=1.5) base case in a 135° bend. Experimental data are used to validate the RANS model predictions for the high curvature base case with a flat bed (FB) and an equilibrium deformed bed (DB). Five curvature ratios (1.5, 3, 5, 8, and 10) and four aspect ratios (5.00, 6.67, 9.09, and 12.50) are investigated. Results show that a decrease in R/B or B/H for the FB cases results in a strong increase in total circulation of the regions associated with the primary cell of cross-stream circulation (Γ+), an increase in maximum b...

Cable clip with segregator and method

Abstract: A cable clip with cable segregator includes ends and a side defining an open space, a series of open ended slots for holding and organizing telecommunications cables defined in the open space and outer grooves for mounting the cable clip with segregator into a mounting opening. The slots can be deep enough to hold two cables and may have an interior profile with a narrow opening, a nominal width, and one or more widened portions for receiving cables of different sizes and shapes. The cable clip with cable segregator can also include trumpet flares around the edges of the ends and side to provide bend radius protection for cables passing through the clip. The present invention also relates to a cable riser with cable clips with segregators mounted in a wall of the riser to hold and organize telecommunications cables that pass into the riser. The present invention also relates to a cable riser with cable clips with segregators mounted in a wall of the riser to hold and organize telecommunications cables that pass into the riser, and cable routing clips mounted within the riser defining a plurality of vertical cable paths within the rises. The present invention also relates to a method of loading cable in the riser into a specific cable path based on the entry location through which the cable enters the riser.

Constant-curvature loss in monomode fibers: an experimental investigation.

Abstract: A new technique for the measurement of constant-curvature (bend) loss as a function of bend radius is described, and it is shown that the influence of transition (microbend) losses can be essentially eliminated. Based on this technique and via the application of curve-fitting procedures and the Newton-Raphson method for two variables, a sensible equivalent step index can be obtained if stress-induced changes in the bent fiber are taken into account. However, the prediction of bend losses at other wavelengths is coarse, and it is shown that, for our fiber, agreement between theory and experiment can be considerably improved via an empirically deduced stress-induced dependence that is far stronger than predicted by published theory.

Bending loss analyses of photonic crystal fibers based on the finite-difference time-domain method

Abstract: This is a report on an effective simulation method for the bending loss analyses of photonic crystal fibers. This method is based on the two-dimensional finite-difference time-domain algorithm and a conformal transformation of the refractive index profile. We observed the temporal dynamics of light waves in a bent fiber in a simulation and obtained the bending loss as a function of bend radius and optical wavelength for the commercial photonic crystal fibers. The accuracy of this method was verified by good agreement between the simulation and experimental data.

Bend-limiting apparatus for a cable

Abstract: A bend-limiting apparatus 20 for attachment to an optical connector 10 has a generally cylindrical shape and includes an axial bore 28 along its central axis for holding an optical cable 30. The front end 22 of the bend-limiting apparatus attaches to the optical connector and has an outside diameter which is comparable in size to the connector. The back end of the bend-limiting apparatus has an outside diameter which is comparable in size to the optical cable. The bend-limiting apparatus is made from a flexible material which is sufficiently stiff to accommodate heavy side loads, but includes a number of grooves 23 that are exclusively positioned on its back half to accommodate light side loads. These grooves preferably extend from an outside surface 29 of the apparatus into the axial bore, and also extend in a circumferential direction at least part way around the apparatus. Such a design effectively limits the minimum bend radius of an optical cable over a wide range of side loads.