Publications related to Magnus effect

Enhancing Wind Farm Performance through Axial Induction and Tilt Control: Insights from Wind Tunnel Experiments

Fernando Porté Agel, Guillem Armengol Barcos

Static axial induction control and tilt control are two strategies that have the potential to increase power production in wind farms, mitigating wake effects and increasing the available power for downstream turbines. In this study, wind tunnel experiment ...

MDPI2024

Experimental investigation of surface roughness effect on a free-flight sphere in a Ludwieg tube

Seong-Hyeon Park

Understanding the aerodynamic coefficients of meteoroid fragments, deorbiting space debris, or launch vehicle stages through atmospheric reentry is essential for ground risk assessments. In high enthalpy flow, surface roughness is a crucial factor affectin ...

KOREAN SOC MECHANICAL ENGINEERS2022

Wind turbine wakes on escarpments: A wind-tunnel study

Fernando Porté Agel, Arslan Salim Dar

In this study, the wake behind a wind turbine located on an escarpment is investigated using particle-image velocimetry in a wind tunnel. Five different escarpment models are used, which vary in the windward side shape from forward facing steps (FFS) with ...

Pergamon-Elsevier Science Ltd2022

Lidar measurements of yawed-wind-turbine wakes: characterization and validation of analytical models

Fernando Porté Agel, Peter Andreas Brugger, Haohua Zong

Wake measurements of a scanning Doppler lidar mounted on the nacelle of a full-scale wind turbine during a wake-steering experiment were used for the characterization of the wake flow, the evaluation of the wake-steering set-up, and the validation of analy ...

2020

A point vortex transportation model for yawed wind turbine wakes

Fernando Porté Agel, Haohua Zong

In this study, stereo particle imaging velocimetry measurements are performed at multiple streamwise locations behind a yawed wind turbine to reveal the formation mechanisms of the counter-rotating vortex pair (CVP), and a point vortex transportation (PVT) ...

Cambridge University Press2020

A bioinspired Separated Flow wing provides turbulence resilience and aerodynamic efficiency for miniature drones

Stefano Mintchev, Matteo Di Luca

Small-scale drones have enough sensing and computing power to find use across a growing number of applications. However, flying in the low-Reynolds number regime remains challenging. High sensitivity to atmospheric turbulence compromises vehicle stability ...

AMER ASSOC ADVANCEMENT SCIENCE2020

Large-Eddy Simulation of Yawed Wind-Turbine Wakes: Comparisons with Wind Tunnel Measurements and Analytical Wake Models

Fernando Porté Agel, Mou Lin

In this study, we validated a wind-turbine parameterisation for large-eddy simulation (LES) of yawed wind-turbine wakes. The presented parameterisation is modified from the rotational actuator disk model (ADMR), which takes account of both thrust and tange ...

2019

Characterization of Wind Turbine Wakes with Nacelle-Mounted Doppler LiDARs and Model Validation in the Presence of Wind Veer

Fernando Porté Agel, Peter Andreas Brugger, Fernando Carbajo Fuertes, Corey Dean Markfort, Mohsen Vahidzadeh

Accurate prediction of wind turbine wakes is important for more efficient design and operation of wind parks. Volumetric wake measurements of nacelle-mounted Doppler lidars are used to characterize the wake of a full-scale wind turbine and to validate an a ...

2019

Understanding turbulent free-surface vortex flows using a Taylor-Couette flow analogy

Giovanni De Cesare

Free-surface vortices have long been studied to develop an understanding of similar rotating flow phenomena observed in nature and technology. However, a complete description of its turbulent three-dimensional flow field still remains elusive. In contrast, ...

Nature Publishing Group2018

Dynamics of falling films on the outside of a vertical rotating cylinder: waves, rivulets and dripping transitions

François Gallaire, Nicolas Igor Jacques Kofman

Falling liquid films on the underside of a plate or on the outside of a rotating cylinder are subject to a destabilizing body force. The evolution of the film topology is determined by interactions between the Kapitza and the Rayleigh-Taylor instability, l ...

Cambridge University Press2017

Numerical simulation of 3D flow in right-angled confluences with bed elevation discordance in both converging channels

Ivan Stojnic

The paper studies a combined effect of bed steps (BS) in both converging channels on the 3D flow in a confluence with alpha = 90 degrees. Nine combinations of bed elevation discordance ratio values in the two channels are analysed. It is shown that: 1) a p ...

Elsevier Science Bv2016

Experimental and theoretical study of wind turbine wakes in yawed conditions

Fernando Porté Agel, Majid Bastankhah

This work is dedicated to systematically studying and predicting the wake characteristics of a yawed wind turbine immersed in a turbulent boundary layer. To achieve this goal, wind tunnel experiments were performed to characterize the wake of a horizontal- ...

Cambridge University Press2016

Second-order sensitivity of parallel shear flows and optimal spanwise-periodic flow modifications

François Gallaire, Edouard Boujo, Andrea Fani

The question of optimal spanwise-periodic modification for the stabilisation of spanwise-invariant flows is addressed. A second-order sensitivity analysis is conducted for the linear temporal stability of parallel flows U-0 subject to small-amplitude spanw ...

Cambridge University Press2015

Stability analysis of boundary layers controlled by miniature vortex generators

Lorenzo Siconolfi

It is currently known that Tollmien–Schlichting (TS) waves can be attenuated by the introduction of spanwise mean velocity gradients in an otherwise two-dimensional boundary layer (BL). The stabilizing effect, associated with an extra turbulence production ...

Cambridge University Press2015

A wind-tunnel investigation of wind-turbine wakes in yawed conditions

Fernando Porté Agel, Majid Bastankhah

Wind-tunnel experiments were performed to study the performance of a model wind turbine and its wake characteristics in a boundary layer under different operating conditions, including different yaw angles and tip speed ratios. High-resolution particle ima ...

Journal of Physics2015

Adjustment of Turbulent Boundary-Layer Flow to Idealized Urban Surfaces: A Large-Eddy Simulation Study

Fernando Porté Agel, Wai Chi Cheng

Large-eddy simulations (LES) are performed to simulate the atmospheric boundary-layer (ABL) flow through idealized urban canopies represented by uniform arrays of cubes in order to better understand atmospheric flow over rural-to-urban surface transitions. ...

Springer2015

Relations between roughness, temperature and dry sliding friction at the atomic scale

Jean-François Molinari, Guillaume Anciaux, Peter Spijker

We investigate the friction of deformable bodies, with nano-scale self-affine fractal rough surfaces, at the atomic scale using molecular dynamics. Different temperatures (0-400 K) are studied, while roughness and applied load are changed. During sliding, ...

Elsevier Sci Ltd2013

Characterization of the Flow Generated in an Annular Test Facility

Peter Ott, Elia Colombo, Dominique Charbonnier, Cécile Deslot

Annular cascades are particularly useful to study the three dimensional phenomena encountered in turbomachines. The Non-Rotating Annular Test Facility of the Swiss Federal Institute of Technology in Lausanne (EPFL) consists in a radial-axial inlet nozzle a ...

2011