Contact between the outer surface of a fuel pellet and the inner surface of the fuel rod cladding can result in several kinds of undesirable behavior. As the pellet swells outward and the cladding creeps down, large stresses are generated in both the pellet and the cladding. This contact may exacerbate chemical degradation of the cladding and the stress may enable rapid propagation of cracks. B...

Characteristics of cladding modes in a photonic crystal fiber (PCF) are numerically analyzed using the plane wave expansion method. The presence of the outer silica ring in the PCF tends to push the optical fields of the cladding modes toward the rim of the PCF, which creates 'ring modes' whose fields are tightly confined in the outer ring. The dispersion of the cladding modes are determined ma...

In this study, the dissimilar metal cladding from a pressure vessel pipe–nozzle mockup for PWR was studied using an optical microscope, scanning electron microscopy, energy-dispersive X-ray spectrometry, back-scattering diffraction, and micro-hardness measurement. The microstructure of SA508 side is non-uniform along fusion boundary, especially at concave convex areas. Martensitic layer (type I...

The pressure and temperature histories on cladding inner and outer surfaces during of LBLOCA (Large Break Loss of Coolant Accident) are considered as boundary conditions for the structural analyses of three cladding materials. Since SiC (Silicon Carbide) has higher yield and ultimate strengths than Zry-4 (Zircaloy-4) under the same primary stresses, SiC has higher primary safety margin than Zry...

The atomic layer deposition (ALD) technology is introduced to enhance the sensitivity of optical fiber cladding mode to surrounding refractive index (SRI) variation. The highly uniform Al2O nanofilm was deposited around the double cladding fiber (DCF) which presents cladding mode resonant feature. With the high refractive index coating, the cladding mode resonant spectrum was tuned. And the sen...

An orientation-dependent displacement sensor based on grating inscription over a fiber core and inner cladding has been demonstrated. The device comprises a short piece of multi-cladding fiber sandwiched between two standard single-mode fibers (SMFs). The grating structure is fabricated by a femtosecond laser side-illumination technique. Two well-defined resonances are achieved by the downstrea...

In this investigation, a laser cladding process with a powder feeding was used to deposit stainless steel 410L (high strength, excellent resistance to abrasion and corrosion, and great laser compatibility) onto railhead (higher strength, heat treated hypereutectoid rail grade manufactured in accordance with the requirements of European standard EN 13674 Part 1 for R400HT grade), to investigate ...

We examine the tuning effect a liquid crystal (LC) cladding has on the lateral leakage loss of TM-like modes in shallow-etched waveguides. For such waveguides with an air cladding, the guided TM-like mode and the unguided cladding TE-like mode can only be phase matched at precisely one angle. We find that for an anisotropic cladding such as an LC, this phase matching is now possible for a range...

The phenomenon of destruction of silica fiber cladding by the fiber fuse effect has been observed for the first time to the authors' knowledge. Experiments on the optical discharge propagation along a fiber were conducted with fibers of decreased cladding thickness. The destruction of fiber cladding led to expansion of the optical discharge plasma and to a decrease of its density. This resulted...