Abstract
Ensuring adequate ventilation of exterior and interior urban spaces is essential for the safety and comfort of inhabitants. Here, we examine how angled features can steer wind into areas with stagnant air, promoting natural ventilation. Using Large Eddy Simulations (LES) and wind tunnel experiments with particle image velocimetry (PIV) measurements, we first examine how louvers, located at the top of a box enclosed on four sides, can improve ventilation in the presence of incoming wind. By varying louver scale, geometry, and angle, we identify a geometric regime wherein louvers capture free-stream air to create sweeping interior flow structures, increasing the Air Exchange Rate (ACH) significantly above that for an equivalent box with an open top. We then show that non-homogeneous louver orientations enhance ventilation, accommodating winds from opposing directions, and address the generalization to taller structures. Finally, we demonstrate the feasibility of replacing louvers with lattice-cut kirigami (“cut paper”), which forms angled chutes when stretched in one direction, and could provide a mechanically preferable solution for adaptive ventilation. Our findings for this idealized system may inform the design of retrofits for urban structures – e.g. canopies above street canyons, and “streeteries” or parklets – capable of promoting ventilation, while simultaneously providing shade.
| Original language | English (US) |
|---|---|
| Article number | 105667 |
| Journal | Journal of Wind Engineering and Industrial Aerodynamics |
| Volume | 246 |
| DOIs | |
| State | Published - Mar 2024 |
Funding
The authors are grateful to Lingxiao Yuan for help with finite element simulations of kirigami, to Luc Deike and Claudia Brunner for helpful discussions, to Cam My Nguyen for help with architectural drawings, to Joseph Vocaturo and Larry McIntyre for help with the experimental setup, and to Michael Vocaturo for access to the wind tunnel. LSM acknowledges financial support from the Princeton Presidential Postdoctoral Research Fellowship and the Momental Foundation. LSM & EBZ acknowledge support from the Army Research Office under contract W911NF-20-1-0216. The simulations presented in this article were performed on computational resources managed and supported by Princeton Research Computing, a consortium of groups including the Princeton Institute for Computational Science and Engineering (PICSciE) and the Office of Information Technology's High Performance Computing Center and Visualization Laboratory at Princeton University. The authors are grateful to Lingxiao Yuan for help with finite element simulations of kirigami, to Luc Deike and Claudia Brunner for helpful discussions, to Cam My Nguyen for help with architectural drawings, to Joseph Vocaturo and Larry McIntyre for help with the experimental setup, and to Michael Vocaturo for access to the wind tunnel. LSM acknowledges financial support from the Princeton Presidential Postdoctoral Research Fellowship and the Momental Foundation . LSM & EBZ acknowledge support from the Army Research Office under contract W911NF-20-1-0216 . The simulations presented in this article were performed on computational resources managed and supported by Princeton Research Computing, a consortium of groups including the Princeton Institute for Computational Science and Engineering (PICSciE) and the Office of Information Technology’s High Performance Computing Center and Visualization Laboratory at Princeton University.
Keywords
- Large Eddy Simulations
- Natural ventilation
- Particle image velocimetry
- Urban flows
- Urban geometry
- Urban ventilation
- Wind steering
- Wind tunnel experiments
ASJC Scopus subject areas
- Civil and Structural Engineering
- Renewable Energy, Sustainability and the Environment
- Mechanical Engineering