1.4 Thesis outline

Introduction 9

performed to validate the predictions with the wind tunnel experiments in a generic 2×2 high-rise building array placed in close proximity in Chapters 2 - 4. 2- Parametric analysis of urban wind energy potential: A comprehensive CFD analysis of the generic 2×2 high-rise building array is performed to assess the influences of various parameters on the mean wind speed, turbulence intensity and wind power density in Chapters 2. 3- Parametric analysis of urban wind energy potential: A comprehensive CFD analysis of the generic 2×2 high-rise buildings array is performed to assess the influences of various building corner modifications on the mean wind speed, turbulence intensity and wind power density in Chapters 3. 4- Parametric analysis of urban wind energy potential: A comprehensive CFD analysis of the generic 6×6 high-rise buildings array is performed to assess the influences of various morphological parameters on the mean wind speed, turbulence intensity and wind power density in Chapters 4. 5- CFD simulation on urban wind energy potential for a realistic high-rise urban area as the case study: High-resolution CFD of urban wind energy potential in the Central district, Hong Kong will be performed to evaluate the urban wind resource assessment for this realistic compact high-rise urban area in Chapters 5. The accuracy of CFD simulations is validated by on-site measurements in both winter and summer periods.

This thesis is composed of four main chapters (Chapter 2-5). The limitations and future research perspectives pertaining to the work presented in these chapters are further discussed in Chapter 6 (Discussion). The conclusions are provided in Chapter 7 (Conclusions). The thesis outline is given below.

Chapter 2: Juan YH, Rezaeiha A, Montazeri H, Blocken B, Wen CY, Yang AS, CFD assessment of wind energy potential for generic high-rise buildings in close proximity: Impact of building arrangement and height. Submitted.

To estimate the urban wind energy potential over generic high-rise urban areas, full-scale CFD simulations are conducted of the wind field for a 2×2 array of generic high-rise buildings in close proximity. Wind-tunnel experimental data are used for validation of the CFD simulations. This chapter presents a systematic parametric analysis of mean wind speed, turbulence intensity and wind power density as influenced by some main geometrical parameters of the building arrangement, including (i) the passage width between the upstream buildings, (ii) the streamwise distance between the upstream and downstream buildings, (iii) the height difference between the upstream and downstream buildings, and (iv) wind turbine type and orientation on the available wind energy potential along the passage between the buildings and on the roofs.

Chapter 3: Juan YH, Rezaeiha A, Montazeri H, Blocken B, Yang AS, CFD assessment of wind energy potential for generic high-rise buildings: Impacts of building corner modifications. Submitted.

In Chapter 3, the urban wind energy potential is assessed for the aforementioned 2×2 highrise building array as a function of different building corner modification parameters, including (i) the impacts of the building corner shape (i.e. sharp, chamfered, and rounded shapes), (ii) the impact of the chamfered corner length, (iii) the rounded corner radius, (iv) the impact of the wind

10 Chapter 1

turbine type and orientation on the available wind power density and reference turbulence intensity along the passage between the buildings, on the roofs and beside the buildings.

Chapter 4: Juan YH, Wen CY, Li ZT, Yang AS, Impacts of urban morphology on improving urban wind energy potential for generic high-rise building arrays, Applied Energy, 299, 117304, 2021.

In Chapter 4, the urban wind energy potential is assessed for a 6×6 array of generic high-rise buildings. It demonstrates a systematic parametric analysis to explore the impact of different morphological parameters, including (i) urban density altered from compact to sparse urban layouts, (ii) building corner shapes of sharp and rounded corners, (iii) urban layouts of in-line and staggered patterns, and (iv) wind directions on the available wind power density and reference turbulence intensity on the roofs and beside the buildings.

Chapter 5: Juan YH, Wen CY, Chen WY, Yang AS, Numerical assessments of wind power potential and installation arrangements in realistic highly urbanized areas, Renewable and Sustainable Energy Reviews, 135, 110165, 2021.

In Chapter 5, the urban wind energy potential applied for a realistic compact high-rise urban area in Central, Hong Kong, is evaluated using CFD simulations. On-site measurements of mean wind speed, wind direction, and turbulence intensity have been conducted for the validation of the CFD simulations in both winter and summer periods. The wind resource assessment is focused on different building features of existing high-rise buildings, including (i) building shape, (ii) roof shape, (iii) presence or absence of upstream obstacles, (iv) arrangements of the integrated building complex, and (v) layouts of parallel high-rise buildings to explore the urban wind energy harvesting around the existing high-rise buildings.