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Wind energy is one of the supremely renewable energy sources and has been widely established worldwide. Due to strong seasonal variations in the wind resource, accurate predictions of wind resource assessment and appropriate wind speed distribution models (for any location) are the significant facets for planning and commissioning wind farms. In this work, the wind characteristics and wind potential assessment of onshore, offshore, and nearshore locations of India—particularly Kayathar in Tamilnadu, the Gulf of Khambhat, and Jafrabad in Gujarat—are statistically analyzed with wind distribution methods. Further, the resource assessments are carried out using Weibull, Rayleigh, gamma, Nakagami, generalized extreme value (GEV), lognormal, inverse Gaussian, Rician, Birnbaum–Sandras, and Bimodal–Weibull distribution methods. Additionally, the advent of artificial intelligence and soft computing techniques with the moth flame optimization (MFO) method leads to superior results in solving complex problems and parameter estimations. The data analytics are carried out in the MATLAB platform, with in-house coding developed for MFO parameters estimated through optimization and other wind distribution parameters using the maximum likelihood method. The observed outcomes show that the MFO method performed well on parameter estimation. Correspondingly, wind power generation was shown to peak at the South West Monsoon periods from June to September, with mean wind speeds ranging from 9 to 12 m/s. Furthermore, the wind speed distribution method of mixed Weibull, Nakagami, and Rician methods performed well in calculating potential assessments for the targeted locations. Likewise, the Gulf of Khambhat (offshore) area has steady wind speeds ranging from 7 to 10 m/s with less turbulence intensity and the highest wind power density of 431 watts/m2. The proposed optimization method proves its potential for accurate assessment of Indian wind conditions in selected locations.

Control of Mach 1.8 circular jet with slanted perforated tabs is studied experimentally. Two sets of perforated tabs were used for this study. The perforation angles were 0° and 30° with respect to axis of the nozzle. The blockage areas of the tabs were 5 %. The mixing enhancements caused by these tabs were studied in the presence of adverse and favorable pressure gradients, corresponding to nozzle pressure ratio (NPR) of 4, 5.74 and 8. For Mach number 1.8, jet NPR 4 corresponds to 30 % adverse pressure gradients and NPR 8 corresponds to 39.37 % favorable pressure gradients. The pressure decay characteristics and shadowgraph images of perforated tabs at different NPR were compared. There is 45 % and 65 % reduction in jet core length were observed for the 0° and 30° perforated tabs respectively in both pitot and shadowgraph experiments in comparison to uncontrolled jet. [ABSTRACT FROM AUTHOR]

AbstractA numerical study was conducted to explore the effective usability of prismatic triangular channel solar air heaters integrated with longitudinal fins and quadrilateral rib turbulators. Using the matrix inversion technique and MATLAB-developed code, the governing equations of the system were solved. The analytical model is confirmed, showing commendable agreement with an average discrepancy of 4.2%. For the constant value of quadrilateral rib conditions, the first law and the thermohydraulic performance of the novel air heating system are analyzed by considering the design and operating conditions of Reynolds number, fin height ratio, fin thickness ratio, and number of fins. The achieved results reveal that the provision of fins with rectangular rib roughness enhances the thermal and effective thermal performance by optimizing fin design parameters, leading to a maximum value of 85.48% and 78.58%, respectively. The comparison results reveal that the present work improves the effective thermal performance by 5.14% to 20.2% up to the Reynolds number of 21600. It is an attractive design, achieving a rise in temperature parameter up to 0.012 W/m2K. [ABSTRACT FROM AUTHOR]

Aim: Transcatheter mitral valve-in-valve (TMViV) replacement for degenerated surgically implanted bioprosthetic valves has been described by both transseptal and transapical approaches. The balloon-expandable Myval transcatheter valve (Meril Life Sciences, Vapi, India) is commonly used for transcatheter valve-in-valve procedures in India. This study aimed to report in-hospital, 30-day, and 1-year outcomes of Myval patients who underwent TMViV in a single tertiary care centre in India., Methods: Symptomatic patients with surgical bioprosthetic mitral valve failure with New York Heart Association (NYHA) class III-IV symptoms, despite optimal medical therapy and high or very high risk for redo surgery, were assigned to TMViV following heart team discussions. Data were retrospectively collected and outcomes assessed., Results: Twenty patients were treated, with mean age 64.4 years, 60% were female, and mean Society of Thoracic Surgeons (STS) predicted risk of operative mortality score was 8.1. The failure mechanism was combined stenosis and regurgitation in 60% of patients. Technical success was achieved in 100% of patients. The mean postprocedure and 30-day gradients were 4.6±2.7 and 6.3±2.1, respectively. None of them had significant valvular or paravalvular leaks or left ventricular outflow tract obstruction. All-cause mortality at 1 year was 10%, and all survivors were in New York Heart Association (NYHA) class I or II., Conclusion: TMViV replacement with a Meril Myval can be safely performed with high technical success, and low 30-day and 1-year mortality., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)