Wind Tunnel Experiment
Computational Fluid Dynamics
Machine Learning
Images: Experiments in campus of Sun Yat-Sen University in ZhuHai, China.
Video：Wind tunnel laboratory
Images：Wind tunnel
Designing green walls to mitigate fine particulate pollution in an idealized urban environment
Leeward planting scheme with LAD = 4 m2/m3, Vd = 0.05 m/s, and 100% wall area coverage was the most efficient green wall design, which reduced up to 50% of the fine particulate concentrations at the pedestrian level (2 m height) in the downstream street.
Images: Designing green walls to mitigate fine particulate pollution in an idealized urban environment (Qian et al., 2024, Read more)
Videos：Droplet transmission in three-dimensional street canyon（Fan et al. 2024）
Indoor-Outdoor droplet dispersion in three-dimensional urban areas with different plan area densities
Droplets exhaled by a patient on the upper and middle floors can enter the apartments on one or two floors below under single-sided ventilation. Although pedestrians and building occupants pose no infection risk to each other in urban areas with λp = 0.25, they are both exposed to high droplet concentrations in dense urban areas with λp = 0.69 and 0.82.
Images: Simulation-based Suggestions for Lockdown Rules in Dense Urban Areas considering Indoor-Outdoor Droplet Transmission under Natural Ventilation Conditions.(Fan et al.2024, Read more)
A venturi-shaped roof（Ye et al. 2024）
Optimum design parameters for a venturi-shaped roof
This study pro-poses integrating all optimum design parameters into a venturi-shaped roof design to alleviate the adverse effects of support structures, which are essential for a stable roof design.
Images: Optimum design parameters for a venturi-shaped roof to maximize the performance of building-integrated wind turbines.(Ye et al.2023,Read more)
Numerical investigation of effects of trees on cross-ventilation of an isolated building
Cross ventilation rates vary with w and d non-linearly despite their minor impact. Moreover, conical or oval foliage with a narrow upper part affects cross ventilation less than cuboidal or V-shaped foliage with a wider upper section. This study recommends trees shorter than 0.25H, and thinner than 0.168H with sparse and conical foliage to be planted upstream of a building, but not within 1H–3.5H, to minimize adverse effects on cross ventilation.
Images: Numerical investigation of effects of trees on cross-ventilation of an isolated building(Zhang et al.2023,Read more)
Videos：Droplet transmission（Fan et al. 2022）
High ambient wind speeds exacerbate the risk of infection
Number of small to medium-sized droplets inhaled by a healthy person under high ambient winds is nearly nine times larger than in low wind speeds.
Images: Numerical investigation of the effects of environmental conditions, droplet size, and social distancing on droplet transmission in a street canyon.(Fan et al.2022,Read more)
Images: Typical PTI (Public Transport Interchange) in Hong Kong(Zhang et al.2022)
Cross-ventilation of a generic PTI (Public Transport Interchange) with various configurations
The two-opening configuration and variants with a large opening are efficient for cross-ventilation; Three- and four-opening configurations need more than one large opening to enhance cross-ventilation; Cross-ventilation rate steadily decreases as internal blockage ratio increases and narrow vertical internal walls and horizontal ones above the opening height limit the decrease in ventilation rate.
Images: Cross-ventilation of a generic building with various configurations ofexternal and internal openings(Zhang et al.2022,Read more)
Images: The lift-up area in Hong Kong(Weerasuriya & Zhang et al. 2020)
Applying ANN model, Genetic Algorithm and CFD simulation for building design: exploring the optimized design for various objectives
By adjusting eight parameters of the ‘lift-up’ building, the proposed framework enlarges, by more than 46% and 37% for ‘hot-calm’ and ‘cold-windy’ climates respectively, the area near a lift-up building where there is pedestrian wind comfort, and by 18% and 10% respectively for the two climates, the area where there is thermal comfort.
Images:Performance evaluation of population-based metaheuristic algorithms and decision-making for multi-objective optimization of building design(Weerasuriya & Zhang et al. 2021, Read more)
Images:Optimizing Lift-up Design to Maximize Pedestrian Wind and Thermal Comfort in ‘Hot-Calm’ and ‘Cold-Windy’ Climates(Weerasuriya & Zhang et al. 2020,Read more)