AbstractRecently, wind power is rapidly gaining attention as one of the major contributors to the global renewable energy industry. Being a non-polluting source of energy generation, wind energy can be harvested using many economic measures. Based on the global cumulative installed capacity, wind power is growing at roughly about 27% since the past decade. This immense growth is majorly driven by intensive research on wind turbines as energy harvesting systems both industrially and domestically. Based on the axis of rotation, wind turbines are classified as horizontal axis wind turbines (HAWTs) and vertical axis wind turbines (VAWTs). Based on the efficiency, HAWTs are superior to VAWTs but relatively more expensive. Savonius-style wind turbines are one of the most studied VAWTs owing to multiple advantages like compact design, simple assembly, excellent self-starting ability at low wind speed and insensitivity to wind direction. However, to address the bottleneck of low efficiency, many researchers are endeavoring to enhance their design.In this study, optimization techniques to improve various design parameters like overlap ratio, end plate diameter and rotor aspect ratio to maximize the efficiency of Savonius-style wind turbine rotor profiles have been investigated. Initially, a two-dimensional numerical model was developed and validated with experimental results. The two-dimensional analysis was conducted using k-ꙍ shear stress transport model. Unsteady Reynold's averaged Navier Stoke's equations have been solved to simulate the flow field of the Savonius-style rotor. This analysis has been performed using the finite volume approach in Fluent 17.2 version. A grid independence study has been performed to minimize the effect of grid size on the flow field characterizations. Subsequently, genetic algorithm (GA) has been used to optimize design variables having discrete values and discontinuous and non-differentiable objective functions. The optimization procedure using a genetic algorithm used the following steps: initialization, evaluation, selection, crossover and lastly mutation. Once the genetic algorithm was initialized, the subsequent evaluation process followed, where each parametric value was evaluated based on the fitness function expressed as the objective function. Then the GA operators i.e., selection,&nbsp; cross over and mutation are then applied. At the end of the GA operation procedure, a new set of values of the design parameter, also known as population, was generated. This procedure was continuously iterated until the convergence criteria were met.&nbsp; The optimization technique implemented on the Savonius-style wind turbine generated design parameters that were able to yield a coefficient of performance value of 0.46.&nbsp; Additionally, contributions of various forces like drag, lift and static pressure have been evaluated to understand the contribution of each type of force on the operation of the Savonius-style rotor profile considered here. It has been observed that a larger lift force and torque were generated by the optimal design of the blade at 0O &lt; θ &lt; 90O, when compared to their conventional non-optimized counterparts. Overall an efficiency gain of 21 % is achieved using the optimized design.Keywords: Savonius-style wind turbine, Reynold's averaged Navier Stoke's equations, genetic algorithms, coefficient of performance, optimization

Genetic Algorithm Based Optimization Technique for Savonius-Style Wind Turbine

Paper Proceedings: https://asmedigitalcollection.asme.org/GTINDIA/GTINDIA2021/volume/85536

ASME 2021 Gas Turbine India Conference (GTINDIA2021)

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.