Experimental Flow Control on a Simplified Ship Helideck

Gallas, Quentin; Lamoureux, Murielle; Monnier, Jean-Claude; Gilliot, Anne; Verbeke, Christophe; Delva, Jérôme

doi:10.2514/1.j055902

Cited by 19 publications

(5 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is because the vectored jet flow with the 𝐶 𝜇 of 0.01 enhances the turbulent mixing and guides it towards the base and deck. The high-TKE region with the mitigated size and length is more likely to avoid intercepting the helicopter path, which reduces the perceived pilot workload (Gallas et al, 2017).…”

Section: Flow Control Resultsmentioning

confidence: 99%

“…The ship air wake downstream the superstructure is characterized by large unsteadiness, massive separation, and complex shear layer interactions. It is therefore acquiring increasing attentions and has been studied numerically and experimentally (Syms, 2008;Forrest and Owen, 2010;Herry et al, 2011;Kääriä et al, 2013;Gallas et al, 2017;Crozon et al, 2018). Due to such complicated flow structures, an uncontrolled ship air wake can lead to detrimental effects on helicopter operations, sailing safety, vessel comfort, and power consumption of propulsion.…”

Section: Introductionmentioning

confidence: 99%

“…For the active flow control methods studied on ships, Gallas et al (2017) implemented steady blowing jet along the hanger sides of Simplified Frigate ONERA (SFO) model. It is found that the blowing jet reduced the re-circulation zone by enhancing mixing activities and entrainment.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Drag reduction of ship airflow using steady Coanda effect

Bensow

et al. 2022

Ocean Engineering

View full text Add to dashboard Cite

Section: Flow Control Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Drag reduction of ship airflow using steady Coanda effect

Bensow

et al. 2022

Ocean Engineering

View full text Add to dashboard Cite

“…Nowadays, aerodynamic flow control is an intensive field of research (Gad-el-Hak 2000). Previously, many research programs around the world were oriented to flow (Greenwell and Barrett 2006, Gallas et al 2017, Shukla et al 2017. The majority of these researches are based on passive flow control devices such as vortex generators.…”

Section: Introductionmentioning

confidence: 99%

Model of the flow on Columnar vortex generator

Bardera¹,

García²

2020

Fluid Dyn. Res.

View full text Add to dashboard Cite

Flow control devices are one of the most commonly studied fields of aerodynamic research in the world. This is because improvements in the aerodynamic performance of any vehicle lead directly to save fuel and money and reduce their operational costs. Another reason is that flow control can reduce the risk of aerial vehicles operating near complex structures which can generate high turbulence intensity levels, supposing a risk for its maneuvers. A passive flow control device used for improving the flow on the ramp of an aircraft carrier is the columnar vortex generator (CVG). Using this device, encouraging results to improve the flow for aerial vehicles which operate on those ships, have been obtained. However, CVG detailed working and vortex generation is not fully known. For that reason, the aim of this paper is to present the results obtained in wind tunnel tests of this passive flow control device. The flow behavior at the front, rear and especially inside it, was analysed. A smoke visualization has been made to the CVG model as a first approach to the flow structure surround and inside the CVG. Flow inside the CVG and specifically its vortex generated has been also analysed using velocity maps obtained by particle image velocimetry (PIV). Tangential and axial PIV planes have been obtained to characterise the vortex and its movement inside the device. These resultant velocity maps have been used to compare the vortex with theoretical models (Rankine and Oseen-Lamb vortex) and establish a new model that predicts the velocity profiles of the vortex generated inside the CVG. Finally, new possible applications using the CVG to improve the flow over a building roof and over the flight deck of a frigate under stern wind is tested by means of PIV in the wind tunnel.

show abstract

“…The flow topology of a frigate's flight deck is critical for flight operations; especially for quick take-off and landing of naval helicopters at various headwind conditions (see NATO (2017) guidelines). In this regard, several studies have been performed numerically and experimentally to predict the air-wake of ships and frigates (Wakefield et al (2002); Syms (2008); Forrest and Owen (2010); Herry (2010); Herry et al (2011); K€ a€ ari€ a et al (2013); Van Muijden et al (2013); Rui et al (2015); Mora (2014); Mora and Meseguer (2015); Vidales (2016); Orbay and Sezer-Uzol (2016); Gallas et al (2017); Shi et al (2017); Crozon et al (2018) and others). The flow past a frigate wake is analogous to that of a finite-width double-backward facing step (Tinney and Ukeiley (2009)), with the region behind the superstructure and the flight deck forming the top step, and the region behind the stern forming the bottom step.…”

Section: Introductionmentioning

confidence: 99%

Qualitative assessment of the bi-stable states in the wake of a finite-width double backward facing step

Rao

Zhang

Minelli

et al. 2019

Journal of Wind Engineering and Industrial Aerodynamics

View full text Add to dashboard Cite

A B S T R A C TThe flow past a simplified frigate shape model which is analogous to a finite-width double backward facing step is investigated numerically using well-resolved large eddy simulations at Re ' 8 Â 10 4 . The geometric configuration of this model permits the occurrence of bi-stable flow states, with an asymmetrical flow topology being observed in the lateral midplane behind each step. In each flow state, the flow at the top step is anti-symmetrical to that observed on the bottom step, and the two flow states are anti-symmetrical to each other. Furthermore, incorporating a base cavity on the top step leads to the suppression of the asymmetrical flow topology on both the steps. The recirculation bubble formed by the downwash at each step is elongated when the base cavity is used, as compared to that observed in either of the two flow states, resulting in a decrease of the drag coefficient. In each of the two flow states, the unequal strength of the streamwise vortices close to the lateral edges on the top step has been identified as the likely cause of the asymmetrical flow on the bottom step.

show abstract

Experimental Flow Control on a Simplified Ship Helideck

Cited by 19 publications

References 13 publications

Drag reduction of ship airflow using steady Coanda effect

Drag reduction of ship airflow using steady Coanda effect

Model of the flow on Columnar vortex generator

Qualitative assessment of the bi-stable states in the wake of a finite-width double backward facing step

Contact Info

Product

Resources

About