An asymmetric blade vertical-axis wind turbine (VAWT) is one of the emerging technologies for harvesting power in the built environment, which has low wind speed. Although asymmetric blade improves VAWT’s performance, the effect of blade pitch angle on its design is hardly ascertained. In this paper, unsteady 2D Reynolds-averaged Navier–Stokes CFD simulations are carried out to investigate the effect of blade pitch angle on the aerodynamic performance of a NACA 63-415 asymmetric blade H-Darrieus VAWT at a low wind speed of 6.0 m/s. Its detailed flow physics at different operating and pitch angle conditions is investigated, and important performance insights are obtained to elucidate its desired blade pitch for performance improvement. The present study shows that positive pitch angle (+ 5°) improves the turbine performance in upwind position, whereas negative pitch angle (− 5°) augments the turbine performance in downwind position as well as causes less wake effect than positive pitch angle. Further, optimal pitch angle (+ 5°) is found out at which the maximum power coefficient of 0.271 is obtained for an operating tip speed ratio 2.4. The present study delineates how desired blade pitch improves the performance of asymmetric blade VAWT for sustainable power generation in the built environment.

不对称叶片垂直轴风力涡轮机（VAWT）是在风速低的建筑环境中收集电力的新兴技术之一。尽管非对称叶片提高了VAWT的性能，但几乎无法确定叶片俯仰角对其设计的影响。在本文中，进行了二维非稳态雷诺平均Navier-Stokes CFD仿真，以研究叶片俯仰角对NACA 63-415非对称叶片H-Darrieus VAWT在低风速6.0 m /时的空气动力性能的影响。 s。研究了其在不同工作角度和桨距角条件下的详细流动物理特性，并且获得了重要的性能见解，以阐明其所需的桨距以改善性能。本研究表明，正俯仰角（+ 5°）改善了涡轮在迎风位置的性能，负俯仰角（− 5°）增强了涡轮在顺风位置的性能，并且比正俯仰角产生的尾流影响小。此外，找到最佳俯仰角（+ 5°），对于操作尖端速度比2.4，可获得0.271的最大功率系数。本研究描述了所需的叶片间距如何提高不对称叶片VAWT的性能，以在建筑环境中实现可持续发电。