Advances in the Quantification of Turbulence: a Wind Resource Characteristic

Wind resource assessment is a critical parameter in a diverse range of considerations within the built environment. Engineers and scientists, engaging in building design, energy conservation/application and air-quality/air-pollution control measures, need to be cognisant of how the associated wind resource imposes increased complexities in their design and modelling processes. In this regard, the topographical heterogeneities within these environments, present significant challenges to quantifying the resource and its turbulent characteristics. Indeed, from the perspective of assessing the wind resource within the built environment, topographical heterogeneity is the primary proponent of turbulence and the main inhibitor to acquiring meaningful measurements. This paper presents two aspects of turbulence assessment within the built environment. Firstly, an analysis of how turbulence is quantified is considered. The industry standard, turbulent intensity (TI) [1] is compared with a proposed alternative metric described as Fourier Dimension modelling (Df). Secondly, the application of the turbulence assessment is considered with respect to how it affects the productivity of small/micro wind turbines in complex environments. The TI metric is the only metric utilised in the consideration of wind turbine productivity though Gaussian distribution analysis [2]. The TDf model has yet to be developed sufficiently to apply it in this regard. [1] IEC, "International Standard 61400-2. Wind Turbines - Part 2: Design requirements for small turbines," ed, 2006. [2] A. Albers "Turbulence Normalisation of Wind Turbine Power Curve Measurements," Deutsche WindGuard Consulting GmbH,2009.