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Faced with environmental and economic challenges, the transition to renewable energies is a priority, particularly in the maritime transport sector, which is subject to increasingly strict regulations. For ships, this adaptation remains complex due to space constraints and the rapid pace of technological advances, sometimes making certain solutions quickly obsolete and generating losses for shipowners. This work explores the use of rotating cylinders, based on the Magnus effect, as an auxiliary propulsion solution for ships. This effect occurs when air circulating around a rotating object creates a pressure difference, generating a force perpendicular to the airflow and the cylinder’s axis of rotation. Compared to other wind technologies, this method has promising potential to reduce emissions and improve energy efficiency. The results of this study highlight the economic and environmental benefits of rotating cylinders, positioning them as a clean and renewable energy for ship propulsion. These findings, consistent with previous work, highlight the rationale of this technology, already adopted by some modern commercial vessels, such as bulk carriers, oil tankers and cruise ships, which seek to optimize their energy efficiency. Thus, despite the challenges, the benefits related to fuel savings and reduced emissions make Flettner cylinders a promising solution for the future of maritime transport.

Dynamic response control of a wind-excited tall building installed with distributed multiple tuned mass dampers (d-MTMDs) is presented. The performance of d-MTMDs is compared with those of single tuned mass damper (STMD) and MTMDs installed at top of the building. The modal frequencies and mode shapes of the building are first determined. Based on the mode shapes of the uncontrolled and controlled building, the most suitable locations are identified for the dampers, in that the TMDs are placed where the modal amplitude of the building is the largest/larger in a particular mode, with each tuned to the modal frequency of the first five modes. The coupled differential equations of motion for the system are derived for the cases with the STMD, MTMDs, and d-MTMDs and solved numerically. Extensive parametric studies are conducted to compare the effectiveness of the three control schemes using STMD, MTMDs, and d-MTMDs by examining the variations in wind-induced responses. The mass ratios, damping ratios of the devices, number of TMDs, and robustness of the TMDs are the parameters of investigation. It is concluded that the MTMDs exhibit improved performance when compared with the STMD. The use of d-MTMDs is most efficient among the three schemes because it can effectively control wind-induced response of the building, while reduced space is required in the installation of the TMDs, as they are placed at various floors.

In this paper, we propose an innovative structural health monitoring (SHM) system for large transmission towers that are frequently subjected to strong winds. The system is based on the strategy of using a static force equilibrium equation to calculate the whole structure’s real-time stress distribution according to its real-time behavior, as captured by the global positioning system (GPS). The reason for adopting this approach is that large transmission towers are fundamentally quasi-static structures and they are not prone to resonance under wind excitations. A case study is used to present the SHM system, then its effectiveness is validated by comparing the simulated SHM results with the exact solution obtained by a realistic time-history dynamic analysis. Additionally, we discuss the use of a new reliability analysis method based on the Ditlevsen’s bounds to assess the real-time structural conditions.

Membranes have been popularly used in the fields of civil engineering and aerospace engineering. When wrinkled, a membrane loses its stiffness in the direction perpendicular to wrinkles and is more sensitive to wind loads. This paper numerically studied the wind-induced responses of a wrinkled membrane and their variations with respect to wind speed, wind direction and wrinkling deformation. Based on the stability theory of plates and shells, the wrinkling deformation of a rectangular membrane under shear was obtained by post-buckling analysis. Then, by using the wind load derived from a wind tunnel test, the dynamic responses of the wrinkled membrane were numerically analyzed for different wind speeds, wind directions and wrinkling deformations. The results indicate the following: (1) the displacement and extreme stresses of a membrane are gradually intensified with an increase in the wind speed; (2) the wind direction plays an important role in the displacement, but it has little effect on the stresses and (3) the displacement increases with the wrinkling deformation, and the extreme stresses are intensified with an increase in the pre-tension. This study on the wind-induced responses of a wrinkled membrane is helpful to the understanding of the complex behavior of a wrinkled membrane under wind loads while reducing the adverse effects of wrinkling deformation and ensuring the dynamic stability of membrane structures.

Under strong winds, bridges may exhibit large dynamic responses. Wind may also endanger the safety of moving vehicles on the roadways as well as on bridges. For regular aerodynamic study of long-span bridges, traffic loads are not typically considered, assuming that bridges will be closed to traffic at high wind speeds. Therefore, bridges are usually tested in wind tunnels or analyzed numerically without considering moving vehicles on them. However, there are numerous possible scenarios under which vehicles may still be on the bridge when higher wind speeds occur. These scenarios include unexpected increase in hurricane forward speed or intensity, evacuation traffic gridlock, accidents/stalled vehicles or rainfall flooding blocking the road ahead, etc. Wind, together with vehicles, will also cause serviceability and bridge fatigue damage issues. The present study will present the framework of wind–vehicle–bridge interaction analysis and its applications, developed in the last decade by the authors' group, focused on the vehicle and bridge safety issues. It consists of the following five parts: (1) A three dimensional finite element analysis framework considering the interaction of wind, bridge and vehicles; (2) experimental facilities development and studies for both static and aerodynamic tests of bridge section models and vehicles; (3) Computation fluid dynamic (CFD) prediction of loading on vehicles; (4) performance evaluation of vehicle safety and bridge fatigue; and (5) bridge vibration mitigations. Case study will also be presented and future research needs are discussed.

This paper proposes a trajectory planning and control strategy to optimally visit a given set of waypoints in the presence of wind. First, aerodynamic properties of quadrotors which affect trajectory planning and tracking performance are investigated. Blade flapping, induced and parasitic drag are derived and an extended method to identify all coefficients from flight test data is developed. Then, a three-step approach is suggested to optimize the trajectory. These steps reduce the size of the optimization problem and thereby increase computational efficiency while still guaranteeing near optimal results. The trajectories are optimized for minimal aerodynamic drag and minimal jerk. The derived smooth trajectory generation is compared with traditional trajectory planning consisting of discrete point to point tracking followed by low-pass filtering. The new trajectories yield a clear reduction in maximal needed thrust and in Euler angle aggressiveness. A thrust vectoring controller is designed, which exploits the a priori trajectory information and identified aerodynamic properties. Its performance is compared to a standard PID controller and results show a reduction in tracking delay and an increase in thrust and attitude angle margins, which overall enable faster flight.

The informational properties of hourly wind data measured in one site in northern Italy from April 1996 to December 2007 were investigated. The data were recorded by a Sodar Rass system, which measures the speed and the direction of the wind at several heights above the ground level. The Fisher-Shannon method was applied to allow discriminating dynamical features in complex time series. The findings point out to height-dependent informational properties of the wind speed. The obtained results shed light on a new perspective which contributes to a better understanding of the complex dynamics of wind phenomenon.

This chapter discusses the different types of the modern controller such as linear quadratic regulator (LQR) and observer designs, which are based on the state-space model for a wind-driven doubly fed induction generator (DFIG)-based system. The control approaches for these controllers are based on the states/outputs feedback system in which the controllers guarantee the closed-loop stability of the system. In this concern, first a comprehensive nonlinear, as well as a linearized mathematical model for each component of the wind-driven DFIG system, is formulated in the d–q axes synchronous frame of reference. Further, the concept of small-signal analysis has been discussed for the linearized model by using eigenvalues method. The simulation studies of the proposed controller performances have been done on the MATLAB/SIMULINK software.

This chapter describes how economic models are used to answer questions about policy changes, specifically in the context of a carbon fee-and-dividend system. A carbon fee-and-dividend is a price on carbon dioxide emissions that returns the revenues gained to ordinary households in the form of a monthly check. The chapter describes, in nontechnical terms, the economic models and modeling processes involved and how they are similar and different from climate models…

BloombergNEF is a leading provider of primary research on clean energy, advanced transport, digital industry, innovative materials, and commodities…

Wind turbines and Solar Photovoltaic (PV) electric energy generators are the lowest cost producers of electricity available in 2019, costing about half as much as a new coal plant’s electric energy (Lazard’s Levelized Cost of Energy Analysis, 2018). They have the important characteristic of delivering electricity without releasing greenhouse gases like carbon dioxide (CO₂). Yet, almost all experts and plans for the future say that wind and solar will not be dominant contributors to electricity generation for the next couple of decades. They say we must continue fossil fuels with their associated greenhouse gases because of problems with renewable generators…

The Atlantic County Utilities Authority (ACUA), located in southern New Jersey, is responsible for treating and managing waste in Atlantic County. At both its solid waste facility (Egg Harbor Township) and wastewater treatment facility (Atlantic City), the ACUA has successfully implemented initiatives including renewable energy projects to reduce emissions. These projects have also saved the Authority money. ACUA’s ability to carry out these projects as a government entity demonstrate that opportunities are available for businesses of all types to have an impact.