The performance of an aerofoil depends upon the angle of attack, leading-edge radius, surface modifications, etc. The aerofoil which has a broader range of attack angle and surface area is responsible for the upliftment in the performance of the aerofoil. The present work deals with the evaluation of the aerofoil spread with dimples over the active surface. The positions and area of spread are modified accordingly and evaluated for the velocity and pressure lineation. The aerofoil with 30% dimples over the active surface is found to possess higher values for the required intents of velocity and pressure at an inlet velocity of 9 m/s. The optimum model with better lineation values is further evaluated for the co-efficient of lift and drag to propose the best design. The best result is obtained at an aerofoil of NACA 8412 series with 30% dimples extension at the rear end placed at 15° angle of attack and the regression analysis is done for the coefficient of lift values.

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The application of wireless electronic devices is increasing nowadays; hence, there is a necessity for electromagnetic wave-absorbing material, which is mechanically stable. Polymer composites with magnetic wood as filler material were fabricated by hand lay-up methods of 6 mm thickness. For the proposed immersion duration, magnetic wood was developed by in situ chemical co-precipitation methods. The microwave absorbing phenomenon is evaluated based on the complex permeability, complex permittivity, dielectric tangent, and magnetic tangent losses. The experimentation was done by vector network analyzer in the frequency range of 8.2–12.4 GHz by X-band and Through-reflect-line (TRL) calibration. It was observed that the reflection losses increase as the immersion time increases from −8.70 dB to −9.30 dB at the frequency range of 10.2 GHz. A similar trend is also followed for the mechanical properties like tensile strength, bending strength, and impact strength with respect to the immersion time. The results revealed that the best mechanical and electromagnetic absorption properties are obtained for the specimens with immersion time of 72 hours. Validation is done for the electromagnetic wave-absorbing properties and mechanical properties by regression analysis, and the experimental data are in close agreement with the regression data.

The design of the spear plays a key role in the Pelton wheel. In general, the spear is useful for increasing the velocity outlet of the nozzle. The maximum amount of the output velocity of the nozzle is mainly controlled by the spear. In this paper, the flow analysis in the Pelton wheel nozzle has been performed by varying the surface design of the spear with different dumps in different shapes and placed at different distances and with different sizes. The simulation in the paper is performed to obtain the optimal shaper and the optimal position for the complexity of the problem. We used the Taguchi design optimization method to obtain the optimal shaper to create the nozzle's higher velocity output. The flow simulation is performed in the ANSYS fluent software and the simulation is performed in fluent with the k-ε; the flow simulation is performed in the two-dimensional analysis. Taguchi optimization is performed in the Minitab software. The most optimal condition for the spear to obtain the maximum velocity is at the following aspect the model is inside a triangle and the overall length of the bump is 1mm and the number of bumps is 4 and the distance between the bumps is 1.75 mm from each other.