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The purpose of this study is to numerically investigate the effect of jet impingement, magnetic field and nanoparticle shape (sphericity) on the hydrodynamic/heat transfer characteristics of nanofluids over stationary and vibrating plates.

A two-dimensional finite volume method-based homogeneous heat transfer model has been developed, validated and used in the present investigation. Three different shapes of non-spherical carbon nanoparticles namely nanotubes, nanorods and nanosheets are used in the analysis. Sphericity-based effective thermal conductivity of nanofluids with Brownian motion of nanoparticles is considered in the investigation. Moreover, the ranges of various comprehensive parameters used in the study are Re = 500 to 900, St = 0.0694 to 0.2083 and Ha = 0 to 80.

The hydrodynamic/heat transfer performance of jet impingement in the case of vibrating plate is 298 per cent higher than that of stationary plate at Re = 500. However, for the case of vibrating plate, a reduction in the heat transfer performance of 23.35 per cent is observed by increasing the jet Reynolds number from 500 to 900. In the case of vibrating plate, the saturation point for Strouhal number is found to be 0.0833 at Re = 900 and Ha = 0. Further decrement in St beyond this limit leads to a drastic reduction in the performance. Moreover, no recirculation in the flow is observed near the stagnation point for jet impingement over vibrating plate. It is also observed that the effect of magnetic field enhances the performance of jet impingement over a stationary plate by 36.18 per cent at Ha = 80 and Re = 900. Whereas, opposite trend is observed for the case of vibrating plate. Furthermore, at Re = 500, the percentage enhancement in the Nuavg values of 3 Vol.% carbon nanofluid with nanosheets, nanorods and nanotubes are found to be 47.53, 26.86 and 26.85 per cent when compared with the value obtained for pure water.

The present results will be useful in choosing nanosheets-based nanofluid as the efficient heat transfer medium in cooling of high power electronic devices. Moreover, the obtained saturation point in the Strouhal number of the vibrating plate will help in cooling of turbine blades, as well as paper and textile drying. Moreover, the developed homogeneous heat transfer model can also be used to study different micro-convection phenomena in nanofluids by considering them as source terms in the momentum equation.

Impingement of jet over two different plate types such as stationary and vibrating is completely analyzed with the use of a validated in-house FVM code. A complete investigation on the influence of external magnetic field on the performance of plate type configuration is evaluated. The three fundamental shapes of carbon nanoparticles are also evaluated to obtain sphericity based hydrodynamic/heat transfer performance of jet impingement.

The purpose of this study is to identify Offshore Wind Energy (OWE) as a key technology that could drive countries toward achieving climate goals. However, there are multiple challenges that this sector faces.

This study aims to identify the challenges faced by the sector globally by systematically reviewing the existing literature in global context and portraying it in the Indian context. Factors are identified using content analysis.

Results suggest high levelized cost of energy as the most discussed challenge for the growth of OWE. Insufficient financial support and policy, initial capital and inadequate technology formed the second, third and fourth most discussed challenges respectively.

To reduce the cost of OWE, the distribution companies in India could adopt feed-in tariffs (FiTs) in the early stages of development and make OWE procurement mandatory. The renewable purchase obligation (RPO) in India is specific to solar and non-solar; policy should accommodate offshore wind-specific RPO targets for each state to reach the 2030 target of 30 GW from OWE.

To the best of the authors’ knowledge, this is the first attempt to study the challenges of OWE development from a global perspective and portray these major challenges in the Indian context and uses content analysis from the existing literature to ascertain the major roadblocks for the development of OWE.

The study identifies the unexplored gap in literature that includes futuristic challenges for OWE from climate change. Future studies can explore the possibilities of forecasting based on climate change scenarios and rank the challenges based on their relevance caused by possible damages.