Urban wind energy potential: Impacts of building corner modifications
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Figure 3.11. Contours of dimensionless power density for case with chamfer length of 0.05B in (a) a vertical plane at y/B = 0 (midplane), (b) a horizontal plane at z/H = 1.03 (just above the roof), (c) and in a vertical plane at y/B = 1.1 (besides the buildings). (d-f) same for case with chamfer length of 0.2B. Note that the high turbulence region (Iref > 0.16) is masked with white, signaling its unsuitability for turbine installation. The black arrow indicates the flow direction. Table 3.4. Ratio of high-turbulence area (Iref > 0.16, unsuitable for turbine installation) over the total area of the planes shown in Fig. 3.11 for different chamfer lengths.
Case ID
Chamfer length, l
Case C1 Case C2 Case C3 Case C4
0.05B 0.10B 0.15B 0.20B
3.5.3
Along the passages between the buildings (y/B = 0) 25% 28% 45% 56%
Selected area Above the roofs (z/H=1.03) 24% 9% 0% 0%
Beside the buildings (y/B = 1.1) 51% 45% 43% 26%
Impact of corner radius
To assess the impact of the corner radius on the wind power density, four radii are studied: r = 1 m, 2 m, 3m, and 4 m (i.e., 0.05B, 0.10B, 0.15B, and 0.20B). Figure 3.12 shows the contour plots of the predicted PD/PDref, with high turbulence regions with Iref > 0.16 masked with white color, over three possible areas for r = 0.05B, and 0.20B. The URAR values are listed in Table 3.5.
