This critical review explores the surface erosion of numerous hydroturbines materials and coatings. This paper provides various aspects of erosion in hydroturbines components. Moreover, it covers the evolution of coating techniques used in different industries such as hydropower plant and materials handling industry. The effect of influencing factors on silt erosion was assessed. However, the evolution of various coating processes was explored comprehensively. Furthermore, the properties of various coatings namely WC, Cr2C3, and Ni/Co coatings were reported. A number of comparative analyses were carried out that can help in selection of coatings on the basis of their mechanical as well as chemical properties. The applications of artificial neural networks (ANN) in the spray industry were explained extensively. The role and implementation of ANN in plasma, high velocity oxy fuel and cold spray coatings are highlighted.

Wire electrical discharge machining (W-EDM) has proven to an appropriate choice for machining hard-to-cut material for obtaining difficult and complex geometries with excellent surface characteristics. The present work investigates the effect of different wire materials, viz. Copper, brass, and Nb-coated brass wire, along with the investigations of W-EDM input factors, viz. pulse-on-duration (Ton), pulse-off-duration (Toff), and current on material removal rate (MRR) and surface roughness (SR). Taguchi’s L9 design has been employed to perform the trials. The maximum MRR of 31.03 mm3/min has been obtained for Nb-coated brass wire as compared to the copper and brass. SR was observed to be least using the brass wire with a value of 3.19 µm. However, the optimum SR value obtained using a Nb-coated brass wire wire was 4.87 µm. Finally, scanning electron microscopy (SEM) for various wire materials revealed the machined surface topography. The Nb-coated wire machined surface shows fewer microcracks, pores, and globule sizes. As per this study, the current work can significantly benefit commercial applications.

With the advancement of the technology the scientist and researcher have come up with the techniques that can analyse and mitigate the climatic data in a favourable picture. Among this techniques, trend analysis has achieved a great appreciation from the researches society. The present study incorporates one of such techniques namely “MANN- KENDALL and Sen’s Slope test performed on the outputs obtained from the hydrological modelling. Specifically, the annual and monthly values of evapotranspiration and runoff as obtained from Arc SWAT hydrological model made to run on the Shetrunji river watershed are used as an input data for M-K test. After the successful run of the M-K test, the annual and monthly plots of ET and runoff are represented and their respective significance values are reported. The result shows the significant changes in the trend of both the parameters. Rainfall ranges from 179.5 mm to 1240.2mm. The value of runoff ranges from 2.56 mm to 503.786mm for annual and for ET ranges from 178.57 mm to 391.19mm for annual . Also, the M-K test shows the range of significance value Zc from 2.58 to -0.03 for ET and 3.44 to -0.83 for Runoff. The present study could help the planners and policy makers to take appropriate decisions in accordance to the welfare of watershed management.

The objective of the presented work is to improve the machining parameters of Multi-Walled Carbon-Nanotube-Reinforced PMMA Nanocomposites using Taguchi's robust design technique. Many variables impact the quality of the completed component throughout the machining process. The quality of machined PNC components is greatly influenced by the surface roughness. Manufacturers can make sure that the finished product fulfils the necessary quality requirements and is cost-effective by optimizing machining settings to achieve the specified surface roughness. Optimizing machining parameters for achieving the desired surface roughness can help reduce production costs by minimizing waste, improving tool life, and reducing the need for post-processing operations. To optimize the process, Three levels of each parameter were chosen for investigation for each such adjustable process parameter. The nanocomposite samples were prepared by dispersing varying concentrations of MWCNTs (0.1 wt.%, 0.5 wt.%, and 1 wt.%) within the PMMA matrix via a 3D mixing approach, followed by injection molding/compression molding Machining was performed on a CNC milling machine using a carbide end mill. Experiments were conducted utilizing Taguchi's technique to generate an experiment design (L27 orthogonal array). Analysis of variance was used to determine the impact of each parameter (ANOVA). The recommended control factor values for the best possible surface finish of PNC are 1.64 m, 400 rpm spindle/cutting velocity, 1.5 mm depth of cut and 0.3 millimeter/revolution feed rate. Surface roughness was shown to be most impacted by cutting speed, followed by feed rate and depth of cut. To determine the relationship between process parameters and quality attributes and regression analysis was used.