Simulation of vorticity wind turbines

Abstract

There are a wide variety of devices behaving essentially as flexible and elastic systems while interacting dynamically with fluids, usually water or air, under normal operating conditions. Interactions of this kind involve a double complexity of the dynamics, as the systems go through large deformation due to the flow actions, and simultaneously, the flow dynamics is strongly influenced by the shape adopted by the systems. The present research adapts mathematical methods, still new to the field, to represent ways of dealing with flows of fluid in bidirectional interactions with those new technologies, and particularly applies them to the exploration of vorticity wind turbines (VWT), a new kind of vertical blade-less turbine that gathers energy from the vortex induced vibrations (VIV) of a relatively short and scalable mast. This research presents a framework for such modeling by coupling the discrete element method (DEM) with the Immersed Boundary Method (IBM), for the representation of VWT; and with the finite volume method (FVM), for solving the Navier-Stokes equations. Simulations show that the VWT achieves the lock-in effect for wind velocities between 9 and 15 m/s, with efficiency values between 20 and 30%. The preliminary results together with logistic and cost-related reasons, make these devices very promising, especially when considering the difficulties of implementing new approaches in developing countries.

Experimental Modeling of Water-Wave Interactions With a Flexible Beam

“…the focus is solely on the response of the flexible mast to water-wave loading and the concomitant changes in fluid flow due to the mast's deformations. Such a rotorless setup will hopefully admit extensions aimed at broadening the application of the experimental data to other FSI problems; for example, in the design of vortex bladeless wind turbines [10]. Fixed-bottom OWTs occur in three forms, defined by their foundations, as shown in Fig.…”

“…10) from which the logarithmically interpolated kL/EI is 7.13 ± 0.24. Finally, the stiffness or torsional spring constant k is then computed as k = (7.13 ± 0.24) EI L(11)= (12.24 ± 0.41) × 10 3 Nm/rad.…”

A co-rotational formulation for quasi-steady aerodynamic nonlinear analysis of frame structures

“…Nonlinear structural dynamic problems are formulated in a vast and diverse set of applications such as: developing new wind turbines systems [2] , [39] , designing suspended bridges or aircraft wings [47] , [6] , predicting failures in power transmission lines [41] , reducing fruit production losses [8] or even studying the movement of aquatic plants [20] . In all of these applications, structures can be modeled using frame elements, and are also submitted to loads caused by the interaction with fluid flows.…”

“…In [28] , a formulation considering nonlinear internal forces with a lumped mass matrix for linear inertial terms was used for modeling wind turbine blades. In [39] a vorticity wind turbine was modeled using the discrete element method concluding that, large displacements must be considered to emulate states of maximum output power. Regarding the nonlinear geometric analysis of wind turbine blades, the linearized equations of motion were solved in [16] , obtaining a good level of agreement between the exact beam theory and formulations using shell elements.…”

Predicting the Parameters of Vortex Bladeless Wind Turbine Using Deep Learning Method of Long Short-Term Memory

“…The results of the numerical solution of the equations demonstrate that high amplitudes occur only in vibration resonance. Sassi et al [9] have utilized the discrete element method with the immersed boundary method to solve Navier-Stokes equations. By analyzing different vibrational parameters and solving differential equations by the Runge-Kutta method, they have concluded that the efficiency values are between 20% and 30% in the lock-in range.…”