Hydrodynamic analysis of flapping-foil thrusters operating beneath the free surface and in waves

Filippas, E.S.; Belibassakis, Kostas

doi:10.1016/j.enganabound.2014.01.008

Cited by 68 publications

(34 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[12]) is applied to obtain the performance of flapping wing sections operating in random head waves, propagating in constant depth H. The studied configuration is schematically shown in Fig. 4.…”

Section: Response Of Flapping Foil In Head Wavesmentioning

confidence: 99%

“…To this aim the 2D panel method developed by Filippas and Belibassakis [12] is applied to numerically model the flapping foil sections in finite submergence. The above solution is shown to be compatible with unsteady linearised theory at low amplitudes, and provides satisfactory comparisons with experiments at higher amplitudes and frequencies, as well as with RANS solvers for the cases of low and medium angles of attack and large Reynolds numbers.…”

Section: Performance In Random Wavesmentioning

confidence: 99%

“…For the detailed investigation of the effects of the free surface on the oscillating body hydrodynamics, in Filippas and Belibassakis [12], a potential-based boundary element method has been developed and applied to the hydrodynamic analysis of a 2D hydrofoil operating beneath the free surface, undergoing flapping motion in harmonic waves. The results are found to be in good agreement with numerical predictions from other methods and experimental data.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Ship propulsion in waves by actively controlled flapping foils

Belibassakis

Filippas

2015

Applied Ocean Research

Self Cite

View full text Add to dashboard Cite

Section: Response Of Flapping Foil In Head Wavesmentioning

confidence: 99%

Section: Performance In Random Wavesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Ship propulsion in waves by actively controlled flapping foils

Belibassakis

Filippas

2015

Applied Ocean Research

Self Cite

View full text Add to dashboard Cite

“…In deep water, the profile of a regular wave can be modelled using linear wave theory, from which the velocity potential is differentiated to derive the horizontal and vertical wave orbital particle velocities, u and v respectively. Further research has incorporated the analysis of fixed foils submerged beneath a surface vessel [16]. Coupling the wave induced vessel motions with that of a spring-loaded foil activates the flapping characteristics required for thrust generation.…”

Section: Flapping Foil Thrust and Power Generationmentioning

confidence: 99%

“…Isshiki uses the term 'wave devouring propulsion' to describe the mechanism of submerged flapping foils generating thrust in waves [13]. Wave devouring propulsion suitably describes the field of research from the initial theory presented by Wu and the theory developed by Grue et al through to recent studies that investigate their application on-board ships [14][15] [16]. Power generation from flapping foils is a more recent body of research, which has seen increased levels of interest due to its potential application as a more efficient flow energy harvesters when compared to their rotary counterparts such as tidal turbines [17].…”

Section: Flapping Foil Thrust and Power Generationmentioning

confidence: 99%

Experimental study of a wave energy scavenging system onboard autonomous surface vessels (ASVs)

Bowker

Townsend

Tan

et al. 2015

OCEANS 2015 - Genova

View full text Add to dashboard Cite

Abstract-Autonomous Surface Vehicles (ASV) have many potential applications in the maritime industry and ocean science. To subsist in the ocean space, an ASV must have the ability to scavenge energy from the surrounding environment. Waves are an abundant source of energy on the ocean surface and a suitable resource for an ASV to scavenge. Flapping foils have been shown to generate thrust in a wavy flow and power in a uniform flow. The aim of this experimental study is to investigate the relationship between flapping foil propulsion and power generation in the context of ASVs. Initial experiments incorporating fully passive flapping foils submerged at the bow and stern of a surface vessel in head waves were performed in a towing tank. The spring-loaded foils were located at the end of rigid pivot arms protruding at the bow and abaft of the vessel. The pivot arms were free to rotate about a location beneath the keel line and restrained by adjustable rotational dampers. In this free condition, wave energy is recovered in the form of work applied by the flapping foils through the rotary dampers which were used to simulate the damping effects of a power take-off device. Thrust was generated under conditions when the pivot arm was fixed. This system, referred to as the Flapping Energy Utilization and Recovery (FLEUR) system, could serve as a dualpurpose wave energy scavenging propulsor and power generator for long-endurance ASVs.

show abstract

Boundary‐Element Methods and Wave Loading on Ships

Κώστας¹,

Kaklis

Politis

et al. 2017

Encyclopedia of Computational Mechanics Second Edition

View full text Add to dashboard Cite

The hydrodynamic problem of a ship moving with constant forward speed while undergoing small‐amplitude oscillatory motions about its mean steady‐state position is modeled as a boundary‐integral equation (BIE) involving surface distributions of the fundamental solution of Laplace's equation and its derivatives and alternative Green functions. The chapter reviews the various low‐order and higher order boundary‐element methods (BEMs) developed for the numerical solution of these BIEs via collocation or Galerkin techniques involving finite‐dimensional bases for representing the involved geometric configuration and approximating the unknown physical quantities. Then, we focus on presenting and discussing recent experience gained from embedding BEMs into isogeometric analysis (IGA) for the linear wave‐resistance problem. Two IGA‐BEM solvers, based on nonuniform rational B‐spline (NURBS) and T‐spline representations of the ship hull, are presented and compared for the so‐called Neumann–Kelvin formulation of this problem. The local refinement capabilities of the adopted T‐spline representation of the ship geometry leads to a solver with higher accuracy and efficiency as compared to the corresponding NURBS‐based solver. Furthermore, the developed hydrodynamic solvers, along with the corresponding ship‐parametric models, are integrated within an optimization environment, which is tested in two optimization problems. The first problem, of local optimization character, focuses on the optimization of the bulbous shape of a container ship against the criterion of minimum wave resistance. The second case performs a global hull‐shape optimization of a container ship targeting the minimization of both the total resistance and the deviation from a target deadweight. The chapter ends with a brief discussion for further research toward broadening the coverage of IGA‐BEM methods in application areas related to ship wave loads.

show abstract

Hydrodynamic analysis of flapping-foil thrusters operating beneath the free surface and in waves

Cited by 68 publications

References 33 publications

Ship propulsion in waves by actively controlled flapping foils

Ship propulsion in waves by actively controlled flapping foils

Experimental study of a wave energy scavenging system onboard autonomous surface vessels (ASVs)

Boundary‐Element Methods and Wave Loading on Ships

Contact Info

Product

Resources

About