Research

Large-scale open-jet testing

Most wind-tunnel tests use small models, typically 1:500 to 1:100 for large structures, in flows that lack the large, low-frequency eddies of real storms, which can understate the peak loads that damage roofs and cladding. The group's earlier studies identified geometric scale and inflow turbulence as key factors in that gap, which led to the LSU WISE open-jet facility (built in two phases): a wall-free jet with a 4 m by 4 m test section that reproduces complete atmospheric boundary-layer turbulence at Reynolds numbers up to 2.3 × 10⁶, depending on the test model, with integral length scales about ten times those of conventional small-scale testing. It supports testing of buildings, solar arrays and other renewable energy installations, wind turbines, bridges, and power transmission lines.

What we found

• Velocity spectra agree well with established formulations, showing both small and large eddies, and surface pressures agree closely with full-scale field data while running 25–300% higher than small-scale tests (Physics of Fluids, 2024).
• On a 1:50 high-rise model, mean cladding pressures matched conventional wind-tunnel values while peak pressures ran higher (ASCE Journal of Structural Design and Construction Practice, 2022).
• Large-scale tests of the Silsoe cube introduced open-jet testing as a tool for structural wind engineering (Engineering Structures, 2022).
• Parapets change roof pressures on low-rise and large industrial buildings, with proposed modifications to ASCE pressure coefficients (Engineering Structures, 2021; Advances in Aerodynamics, 2021; Architectural Science Review, 2023).

Also in this area

Boundary-layer wind tunnel testing; the effect of model scale and inflow turbulence on peak loads (Solar Energy, 2016); internal pressures in buildings with openings and sudden breaching (Wind and Structures, 2013); wind-induced response of tall buildings by pressure integration (Alexandria Engineering Journal, 2013); aerodynamic and aeroelastic wind tunnel studies of Milan's CityLife towers at Politecnico di Milano; and wind-tunnel and full-scale tests of trees for vegetated building envelopes (Wind and Structures, 2013). Before LSU, Dr. Aly calibrated the flow-production machines of Florida International University’s Wall of Wind for full-scale hurricane testing and first-authored its design paper (ASCE-EMI Special Publication, 2013).

In pictures

Aerodynamics, CFD, and machine learning

We use large-eddy simulation (LES) and Reynolds-averaged (RANS) models to compute wind flow around buildings, bridges, solar arrays, and airfoils, and machine learning to make those simulations faster and more accurate. Part of this work began during Dr. Aly's U.S. Air Force Research Laboratory Summer Faculty Fellowships (2022 and 2023), computational residencies that integrated machine learning with OpenFOAM.

What we found

• Machine learning coupled with CFD predicts wind loads on solar panels up to 10,000 times faster than conventional CFD, with accuracy preserved, and identified −15° as the optimal stow angle for a single-axis solar tracker during wind events (Sustainable Cities and Society, 2023).
• A deep-learning model trained on LES data improves eddy-viscosity predictions in RANS simulations of wind pressures on bluff bodies, especially in separation zones; the trained model ran in about 6 minutes, against about 24 minutes for k-ε, 45 minutes for k-ω SST, and 182 hours for LES (Journal of Applied Fluid Mechanics, 2024).
• For pitching and plunging airfoils, higher motion frequencies increase thrust, thinner airfoils generate more thrust, pivot locations near the leading edge are favorable, and an upstream vortex produces sharp lift transients (AIAA Journal, 2026).
• An interpolation approach that reuses inflow data across grids lowers the cost of LES without loss of fidelity (Journal of Building Engineering, 2021).
• A sole-authored perspective on how machine learning is reshaping CFD accuracy and speed (Fluids, 2025).

Also in this area

Large-eddy simulation of peak roof pressures on low-rise buildings, compared with full-scale and wind-tunnel data (Wind and Structures, 2020); CFD of scour countermeasures, in which flow attachments such as a delta vane reduced bed shear stress at bridge piers and monopile foundations (Ocean Engineering, 2021), and LES of pier scour (Journal of Applied Fluid Mechanics, 2023); and urban heat island mitigation through building geometry (Theoretical and Applied Climatology, 2022).

Structural dynamics, smart structures, and control

Tall buildings, wind turbines, and slender structures can vibrate excessively under wind and earthquakes. We design passive, semi-active, and active control systems, from tuned mass dampers to magneto-rheological (MR) smart dampers, and develop the theory to tune them.

What we found

• A tuned pendulum pounding mass damper, with a pounding surface near static equilibrium, is more robust than conventional tuned mass dampers; experiments showed reductions of 55.7% in base shear, 41% in base moment, and 40% in inter-story drift ratio (Soil Dynamics and Earthquake Engineering, 2023).
• A physics-based theory of semiactive control gains, built on a Lyapunov function, tunes smart dampers in multi-degree-of-freedom structures analytically, without iterative numerical simulation (ASCE Journal of Structural Engineering, 2019).
• A pendulum pounding damper proposed for wind turbines (Engineering Structures, 2021), with automated controller tuning and probabilistic frameworks that extend wind-turbine fatigue life under multiple hazards.
• Structural control and vibration issues in wind turbines: a review (Engineering Structures, 2020).
• Bracing stiffness and viscoelastic damping for vibration control in buildings (ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, 2025).

Also in this area

An energy-based probabilistic approach to smart-damper efficacy (Smart Materials and Structures, 2008); fast hybrid testing of controlled smart dampers on nonlinear structures (Arabian Journal for Science and Engineering, 2014); MR dampers with lever mechanisms and bracing for tall buildings (The Structural Design of Tall and Special Buildings, 2011); robust tuned mass dampers under multidirectional wind (The Structural Design of Tall and Special Buildings, 2014); and vibration control of traffic mast arms (Experimental Techniques, 2021).

Wind-resilient solar, agrivoltaics, and wind energy

Solar arrays, solar trackers, agrivoltaic systems, and wind turbines are being built in hurricane-prone regions where design guidance for wind loads is limited. We measure and model their wind loads and dynamic response so they can be designed to survive.

What we found

• Rooftop PV arrays reduced total wind-induced forces on a low-rise gable roof by 45–63% (Sustainable and Resilient Infrastructure, 2023).
• In a solar-farm case study from Hurricane Maria, rebuilding raised costs by 50%, while accounting for accurate wind loads in the original design would have raised initial costs by only 2% (white paper, 2025).
• In large-scale open-jet tests on a mono-slope roof building, a rooftop solar panel did not increase wind forces and reduced the pressure at the roof’s leading edge by 40%.
• Geometric scale is a primary source of discrepancies in measured peak wind loads on solar panels (Solar Energy, 2016).
• A review of agrivoltaic systems (Sustainability, 2024) and a structural and wind-dynamics approach to agrivoltaic resilience (Frontiers in Horticulture, 2026).

Also in this area

Doctoral research on torsional galloping, an aeroelastic instability, of single-axis solar trackers (2026) and machine-learning prediction of wind-turbine blade fatigue (Structural Durability & Health Monitoring, 2024); vibration and fatigue mitigation for wind turbines; and hydro-aero coupling in floating offshore wind turbines (Journal of Structural Design and Construction Practice, 2024), building on Dr. Aly's offshore wind turbine experiments at Western University's Boundary Layer Wind Tunnel Laboratory (2012–2013).

Wind, waves, and water

Offshore wind turbines and coastal infrastructure face wind and water together. At Western University’s Boundary Layer Wind Tunnel Laboratory, Dr. Aly designed and ran experiments on offshore wind turbines (2012–2013), and the group’s CFD work extends to the water flows that scour foundations.

What we found

• A review of hydro-aero coupling shows how waves and platform motion, including surge, change the aerodynamic performance of floating offshore wind turbines (Journal of Structural Design and Construction Practice, 2024).
• Flow attachments such as a delta vane reduce bed shear stress, and with it scour, at bridge piers, elevated buildings, and monopile wind-turbine foundations (Ocean Engineering, 2021); large-eddy simulation captures the scour-driving flow better than RANS (Journal of Applied Fluid Mechanics, 2023).

Also in this area

Vibration of wind turbines under combined wind, wave, and earthquake loading, under Structural dynamics.

Transportation infrastructure

• An overheight vehicle impact avoidance and incident detection system (U.S. Patent 12,049,233 B2, 2024), which grew out of a case study on protecting bridges against overheight vehicles; in that study, a sandwich sacrificial cushion of high-impact rubber reduced the girder's lateral deflection by 89% and cut stresses in the girder's bottom flange and the vehicle's top by 82% and 25% (Steel and Composite Structures, 2022).
• Wind-induced vibration of traffic mast arms (Experimental Techniques, 2021) and wind loads on overhead sign structures (Applied Sciences, 2023).
• Bridge aerodynamics with open-jet testing, Reynolds-number effects, and green-energy integration (Wind, 2025).