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In this work, an attempt is made to study the effect of heat input on mechanical and metallurgical properties of Tungsten Inert Gas (TIG) welded Hastelloy C-276 sheets. Hastelloy C-276 sheets of thickness 1.6mm were used throughout this study. Three butt joints were made by varying the values of welding current in the steps of 1 Ampere. The weld quality was assessed by measuring bead geometry, tensile strength and microhardness. From the experimental results, it was found that the hardness proportionally varied with the change in welding current whereas tensile strength first increased and then decreased with increase in welding current. The weld property variation is discussed with the aid of microstructures taken from Scanning Electron Microscope (SEM), Energy Dispersion Spectroscopy (EDS) and X-ray Diffractometer (XRD).

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The dynamic behaviour of the straight–type Darrieus turbine with leading-edge protuberance (LEP) was analysed under various solidity ratios at several tip speed ratios through experiments. The Darrieus turbine is a type of Vertical Axis Wind Turbine (VAWT) which uses wind energy to generate electricity. This type of turbine was subjected to vortex-induced and buffeting types of vibrations. These vibrations were more sensitive to the number of blades and tip speed ratios. Based on the experimental measurements, the results revealed that, at a low tip speed ratio, the four-bladed turbine exhibits lesser vortex-induced vibrations than those of the three and five-bladed turbines. However, at a high tip speed ratio, the three-bladed configuration operates well against the vortex-induced vibrations. In the case of buffeting, a three-bladed turbine diminishes the dynamic oscillations at both low and high tip speed ratios, whereas the four and five-bladed turbines induce dynamic oscillations at slightly higher amplitudes. However, the amplitude of buffeting is smaller than those of vortex-induced vibrations.