Andrea Freda

Andrea Freda
Università degli Studi di Genova | UNIGE · Dipartimento di Ingegneria civile, chimica e ambientale (DICCA)

PhD

About

54
Publications
6,169
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
554
Citations
Citations since 2016
19 Research Items
447 Citations
2016201720182019202020212022020406080
2016201720182019202020212022020406080
2016201720182019202020212022020406080
2016201720182019202020212022020406080

Publications

Publications (54)
Article
A vaulted free-standing canopy roof to be built in a University Campus is investigated by wind tunnel experiments to address the lack of information for this structural shape. First set of tests investigates the model in isolated configuration; second set reproduces the nearby buildings as well as the topography of the surroundings; third set is ca...
Article
Full-text available
Lattice towers are used in several fields such as radio and television broadcasting, wireless communication or mobile networking. These are lightweight structures which are used to support specific equipment to certain heights such as for examples antennas needed for signal transmission. The purpose of this paper is to investigate the influence of...
Article
This paper aims to investigate the innovative design of a ducted horizontal-axis wind turbine and to compare its energy production with a traditional free turbine for energy harvesting, both at laboratory and on relevant environment scales. The ducted wind turbine was designed considering a convergent-divergent duct, with the turbine in the throat...
Article
Full-text available
In operational conditions wind is the main environmental source of measurement biases for catching-type precipitation gauges. The gauge geometry induces a deformation of the surrounding airflow pattern, which is generally characterized by relevant updraft zones in front of the collector and above it. This effect deviates the trajectories of the lig...
Chapter
Due to their natural location, ports are very exposed to extreme weather conditions. Considering in particular terminal containers, the piled containers can fall and get damaged under strong wind. This paper describes a wide research activity aimed at the evaluation of wind effects on containers stability. The analytical formulation of stability co...
Article
Wind flow modeling in urban areas is usually performed by means of Wind-Tunnel (WT) testing or Computational Fluid Dynamics (CFD) simulations. Results obtained with both techniques can be affected by the boundary conditions. This study aims at investigating how two sets of inflow conditions, termed set 1 and set 2 and calculated respectively using...
Article
A Fluid-Structure Interaction (FSI) conventional case study is proposed to be used as a benchmark for numerical analyses. Experimental tests were carried out to provide targets for comparisons; in particular, the study regarded the estimate of the deformed configuration ("flying shape" in the sailing field) of a square sail under a uniform flow reg...
Conference Paper
Electrical energy production by wind energy has assumed more and more relevance in the last years. This paper presents the design of a ducted horizontal axis wind turbine, in order to enhance the performance. The study compares the energy production of a ducted turbine to a traditional free turbine, highlighting the different features. In the first...
Article
Wind flow in urban areas is strongly affected by the urban geometry. In the last decades most of the geometries used to reproduce urban areas, both in wind-tunnel (WT) tests and Computational Fluid Dynamics (CFD) simulations, were simplified compared to reality in order to limit experimental effort and computational costs. However, it is unclear to...
Article
This paper presents the results of an experimental study aimed at investigating the urban boundary layer in a district of Livorno city, in Tuscany. The wind flow over this area has been measured in the wind tunnel of the University of Genova using a physical model in scale 1:300. Two sets of measurements have been carried out, aimed at measuring th...
Conference Paper
In the present study the relative importance of several model parameters related to RANS simulation of urban wind flow was investigated, using a district of Livorno city (Italy) as a case study for which earlier wind tunnel tests were performed. CFD simulations were performed at the same reduced scale (1:300) and for the same inflow wind direction...
Conference Paper
Wind flow modeling in urban areas is influenced by many uncertainties, such as geometric detailing, inflow and boundary conditions, numerical approach (RANS, LES, and DNS) and turbulence model. This study aims to investigate how the different inflow conditions that are usually adopted to simulate urban wind flows may affect the accuracy of the resu...
Conference Paper
Full-text available
The generation of aerodynamic forces of oscillating bodies is the result of several physical phenomena interacting each other. The classification of Vortex-Induced Excitation (VIE) and Motion-Induced Excitation (MIE), together with their modeling, is only partially satisfactory mostly due to the mentioned interactions. In this paper, we describe th...
Article
This study discusses the uncertainties inherent in the galloping onset conditions of wind-excited structural elements using error propagation techniques. The problem is dealt with considering two different technical situations: the estimate of the critical wind velocity for engineering applications and the assessment of the galloping factor derived...
Conference Paper
In the present study the relative importance of several model parameters related to RANS simulation of urban wind flow was investigated, using a district of Livorno city (Italy) as a case study for which earlier wind tunnel tests were performed. CFD simulations were performed at the same reduced scale (1:300) and for the same inflow wind direction...
Conference Paper
Wind flow modeling in urban areas is influenced by many uncertainties, such as geometric detailing, inflow and boundary conditions, numerical approach (RANS, LES, and DNS) and turbulence model. This study aims to investigate how the different inflow conditions that are usually adopted to simulate urban wind flows may affect the accuracy of the resu...
Conference Paper
This paper presents the monitoring campaign carried out over a small size vertical axis wind turbine in the experimental facility of the Savona Harbour. The monitoring activity integrates the wind field and power production records with the structural response parameters. The dynamic response is acquired by servo-accelerometers positioned at the to...
Conference Paper
The aim of this study is to assess wind flow modelling capabilities for a selected urban area-"Quartiere la Venezia" in Livorno city (Italy)-by means of wind tunnel tests and CFD simulations. Both wind tunnel tests and CFD simulations were performed on a reduced-scale model. In addition, in the CFD simulations two levels of detail were tested. A co...
Conference Paper
The aim of this study is to assess wind flow modelling capabilities for a selected urban area-"Quartiere la Venezia" in Livorno city (Italy)-by means of wind tunnel tests and CFD simulations. Both wind tunnel tests and CFD simulations were performed on a reduced-scale model. In addition, in the CFD simulations two levels of detail were tested. A co...
Article
The practice of reproducing wind tunnel tests by means of CFD numerical simulations, which is known as numerical wind tunnel (NWT), is becoming quite common in many research fields of wind engineering. Wind tunnel tests can provide the indispensable validation data needed for CFD numerical simulations; at the same time, CFD can be considered a comp...
Conference Paper
Full-text available
In the present study, the wind flow in the urban boundary layer and within the canopy layer of a complex urban area in Livorno city has been investigated numerically and experimentally. In particular, the quarter " La Venezia " has been selected as case study and a model of this area at the reduced scale 1:300 has been studied. Wind tunnel tests on...
Article
Full-text available
Lighting poles and antenna masts are typically high, slender and light structures. Moreover, they are often characterized by distributed eccentricities that make very complex their shape. Experience teaches that this structural type frequently suffers severe damage and even collapses due to wind actions. To understand and interpret the aerodynamic...
Conference Paper
A square sectional model immersed in a homogeneous and smooth flow can undergo two main aeroelastic phenomena: Vortex-Induced Vibrations (VIV) and galloping. The former takes place in a limited range of flow velocities, and its amplitude is self-limiting. The galloping phenomenon develops over a critical velocity, with amplitudes increasing with th...
Conference Paper
Full-text available
Unsteady aerodynamic forces on moving bodies are often classified as Vortex Induced Excitation and Motion Induced Excitation. These two classes of forces coexist and interact with each other in rather complicated manner. In order to shed some light on this phenomenon an experimental campaign involving pressure measurements of a square prism with co...
Conference Paper
Full-text available
This study aims at evaluating the efficiency of a three-blade Savonius small vertical axis wind turbine (VAWT), surrounded by a power augmentation guide vane (PAGV). The PAGV system is designed to improve the wind rotor performance by increasing the oncoming wind speed and steering it to an optimum flow angle before it interacts with the rotor blad...
Conference Paper
Full-text available
This paper presents the results of an experimental study aimed at investigating the urban flow in a canopy layer. A quarter of Livorno city, placed in Tuscany, has been selected as test case and reproduced in scale 1:300 in the wind tunnel of the Department of Civil, Chemical, and Environmental Engineering (DICCA) of the University of Genova. Two s...
Article
The influence of corner shaping and turbulence intensity on the aerodynamic stability of square cylinders is studied with a quasi-static approach. Beside the sharp-edge corner condition, two different rounded-corner radii (r/b=1/15 and 2/15) are considered. The stability analyses are based on aerodynamic coefficients derived through static wind tun...
Article
The influence of corner shaping on the aerodynamic behavior of square cylinders is studied through wind tunnel tests. Beside the sharp-edge corner condition considered as a benchmark, two different rounded-corner radii (r/b=1/15 and 2/15) are studied. Global forces and surface pressure are simultaneously measured in the Reynolds number range betwee...
Conference Paper
Wind tunnel tests on sectional models are largely used to derive both aerodynamic forces and flutter derivatives of long-span bridge decks. The most common situation for this typology of bridges is to be far from the ground. Wind tunnel tests on sectional models are therefore generally carried out in a homogeneous and smooth flow. However, due to t...
Article
This paper concerns the study of galloping critical conditions on square cylinders with an arbitrary attitude in the wind flow. It is based on a consistent theoretical model of wind actions, which permits the analysis of a generic-shaped cross-section. A generalized definition of the aerodynamic damping matrix as function of both the angle of incid...
Article
The safety of railway operations under wind actions has recently become a topical matter due to the development of high-speed trains, which are very sensitive to crosswind conditions. For this reason, RFI (the Italian railway network) has entrusted the University of Genoa with a study of the wind hazard of the Rome–Naples High Speed (HS)/High Capac...
Article
The safety of railway operation under wind actions has recently become a topical matter due to the development of high-speed trains, which are very sensitive to crosswind conditions. For this reason, RFI (the Italian railway network) has entrusted the University of Genoa with a study of the wind hazard of the Rome–Naples High Speed (HS)/High Capaci...
Conference Paper
This paper concerns the study of galloping critical conditions on square cylinders having an arbitrary attitude in the wind flow. It is based on a consistent theoretical model of wind actions which permits the analysis of a generic-shaped cross-section. The availability of specific experimental data allows a sound definition of aerodynamic actions....
Conference Paper
Strong winds are a relevant issue in the management of several transportation and power generation infrastructures. The short-term wind speed forecast is considered an important tool for the reduction of the operation risk and of the economical loss due to possible operation outages. In last decades, the short-term forecast of wind speed has been a...
Conference Paper
Full-text available
Due to their very light structural weight, high-speed trains are very sensitive to the action of cross-winds. A common tool for the estimation of the safety of trains against cross-winds is provided by the Characteristic Wind Curves (CWC), that are evaluated in wind-tunnel tests and depend on the wind speed and direction at the railway line. The es...
Conference Paper
The construction of high-speed railway lines has led to the development of trains that – due to a very light weight – are sensitive to the action of cross winds. The present paper summarizes the main aspects of a new methodology to perform the cross wind risk analysis on railway lines, and its application to the Rome-Naples high-speed/high capacity...
Conference Paper
Full-text available
This paper describes a new methodology to perform the cross wind risk analysis on railway lines. This study consists in the evaluation of the probability of rail vehicle's overturning when it is running on a railway line under the action of cross wind. According to the new methodology described in this paper, the cross wind risk analysis is based o...
Conference Paper
La previsione a breve termini dei fenomeni eolici di maggiore intensità è uno strumento sempre più diffuso nella gestione di grandi infrastrutture, sia in ambito dei trasporti sia nella produzione di energia, poiché consente un'efficace riduzione sia dei rischi a cose e persone sia delle perdite economiche legate a improvvise interruzioni delle att...
Conference Paper
A wide research project is currently carried out by the University of Genova and Rete Ferroviaria Italiana in order to analyse the wind climate of a pilot high-speed/high-capacity railway line, namely the Rome-Naples railway line in Italy. The project, aimed at developing an efficient procedure that can be applied to any railway line, involves two...
Article
Full-text available
Quasi-steady approaches have been often adopted to model wind forces on moving cylinders in cross-flow and to study instability conditions of rigid cylinders supported by visco-elastic devices. Recently, much attention has been devoted to the experimental study of inclined and/or yawed circular cylinders detecting dynamical phenomena such as gallop...
Conference Paper
Quasi-static hypotheses have often been adopted both to model wind forces on moving cylinders in cross-flow and to study instability conditions of rigid cylinders supported by visco-elastic devices. Recently, much attention has been devoted to the experimental study of inclined and/or yawed circular cylinders. detecting peculiar dynamical phenomena...
Conference Paper
Quasi-steady hypotheses have been often adopted to model wind forces on moving cylinders in cross-flow and to study instability conditions of spring-supported rigid cylinders. Recently, much attention has been paid to the experimental study of inclined and/or yawed circular cylinders detecting peculiar dynamical phenomena such as galloping-like ins...
Conference Paper
Quasi-static hypotheses have been often adopted to model Wind forces on moving cylinders in cross-flow and to study instability conditions of rigid cylinders supported by visco-elastic devices. Recently, much attention has been devoted to the experimental study of inclined and/or yawed circular cylinders detecting peculiar dynamical phenomena such...
Conference Paper
The present paper studies the wind-excited response of harbor crane structural elements by applying the gust effect factor technique. Since this coefficient has been defined for slender-line vertical structures, the study of the response of this particular structural typology requires a new definition of the element geometry and kinematics and of t...
Conference Paper
La presente memoria studia la risposta all’azione del vento di elementi di gru portuali mediante la tecnica del fattore di raffica degli effetti. Poiché questo coefficiente è stato definito per strutture snelle verticali, lo studio della risposta di questa particolare tipologia richiede modifiche sia sulla geometria e sulla cinematica dell’elemento...

Network

Cited By

Projects