Analysis, Design and Validation of a Vaned Diffuser for Improved Fish Friendliness

The primary cause of mechanical-related fish injury and mortality in turbomachinery is blade strike. Fish contained in the flow may strike with the rotor blades and the fixed diffuser vanes, the latter being a non-negligible factor causing fish damage in the pump system. In this study, an experiment-based correlation of fish mutilation ratio acts as critical strike velocity. The relation between strike damage in a vaned diffuser and the theoretical pump head is presented as a function of specific speed. As an example, a vaned diffuser is designed for a single-bladed, mixed-flow impeller with the purpose of improving fish friendliness. This pump can be scaled to operate with a head up to 14 m at peak efficiency, without fish damage in the diffuser. Subsequently, experiments are conducted to show the retained pump performance as well as the great improvement of fish friendliness

Nanoscale characterization and magnetic property of NiCoCu/Cu multilayer nanowires

NiCo/Cu multilayer nanowires have been successfully fabricated by a pulse electrodeposition technique using anodic aluminum oxide templates, and their chemistry, crystal structure andmagnetic properties characterized at the nanoscale. It was found that each individual nanowirehad a regular periodic structure. The NiCo/Cu nanowires also displayed a continuousmorphology, smooth surface and polycrystalline fcc structure. EDX elemental mappingsconfirmed the presence of nickel, cobalt and copper, which appear clearly with a periodicdistribution throughout the samples. Both the NiCo and Cu layers were polycrystalline and theaverage length of the interlayers between NiCo and Cu layers was approximately 3–4 nm. TheNiCo/Cu nanowire arrays had an easy axis parallel to the length of wire and exhibited acurling magnetization reversal mechanism. This study highlights the basis morphological,structural and chemical information for NiCoCu/Cu multilayer nanowires, which is critical fortheir applications in nanodevices and nanoelectronics