Creative Turbulence for Improving Energy Efficiency and Engineering Safety

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Flow turbulence is omnipresent in many engineering applications including solar photovoltaic panels, wind turbines, and bridge stay cables. Despite more than a century of intensive research on flow turbulence, a comprehensive understanding of this ‘mysterious creature' remains elusive. Among the myriad of papers published, especially the more recent ones, many are largely theoretical, hindering the direct exploitation of these advances in practical engineering systems. Pragmatically, to a solar photovoltaic panel, strong atmospheric wind, even though it may be a challenge to the supporting structures, is a welcome guest for cooling the panel and thus, improves the energy conversion efficiency. This calls for simple, functional, ingenious means to manipulate the wind over these panels to effectively augment heat convection. Through rigorous investigations powered by NSERC Discovery, ribs and ribbons have emerged as promising candidates. On this pursuit, the endeavour to better understanding of the turbulent flow with the proper convective features is a must. Thus, the practically oriented, fundamental engineering uncovering of good turbulence is the thrust of the proposed Discovery. Improving wind turbine performance under atmospheric turbulent wind shear is the second practical objective. The primary goal is to unearth the details concerning the wind turbulence in homogenizing the wind shear, and the resulting largely constructive effect on the performance of the wind turbine. Furthermore, the underlying mechanisms involved in wind turbulence in breaking down the well-organized, vortical flow structures of the incoming wake from an upstream turbine are sought. This knowledge is critical to engineering mitigation of the adverse effects of the wake on multiple wind turbines downstream. To this end, improved insights on the aerodynamic stall delay and lift enhancement by wind turbulence are needed. The third turbulence objective is alleviation of turbulent wind induced stay cable vibrations. We recently discovered that detrimental galloping necessitates the to and fro swinging of the dry cable across the critical drag valley. The perplexing opposing role of wind turbulence in promoting and yet, demoting this damaging dry cable galloping is both fundamentally intriguing and practically important.