Vortex generator jets - Means for flow separation control

Johnston, J. P.; Nishi, Michihiro

doi:10.2514/3.25155

Cited by 262 publications

(81 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The principle of flow control is the same as for vane-type VGs: momentum transfer between the free-stream and the near-wall region. Johnston and Nishi (1990) appear to be the first to demonstrate that VG jets do indeed generate streamwise vortices and also showed that they could reduce turbulent flow separation when the jet-to-free-stream velocity ratio was above 0.8. Compton and Johnston (1992) showed that the vortices produced were similar to vane-type VGs, but decayed faster downstream.…”

Section: Introductionmentioning

confidence: 99%

Dielectric-barrier-discharge vortex generators: characterisation and optimisation for flow separation control

Jukes

Choi

2011

Exp Fluids

View full text Add to dashboard Cite

We investigated the use of dielectric-barrierdischarge plasma actuators as vortex generators for flow separation control applications. Plasma actuators were placed at a yaw angle to the oncoming flow, so that they produced a spanwise wall jet. Through interaction with the oncoming boundary layer, this created a streamwise longitudinal vortex. In this experimental investigation, the effect of yaw angle, actuator length and plasma-induced velocity ratio was studied. Particular attention was given to the vortex formation mechanism and its development downstream. The DBD plasma actuators were then applied in the form of co-rotating and counter-rotating vortex arrays to control flow separation over a trailing-edge ramp. It was found that the vortex generators were successful in reducing the separation region, even at plasma-to-freestream velocity ratios of less than 10%.

show abstract

Section: Introductionmentioning

confidence: 99%

Dielectric-barrier-discharge vortex generators: characterisation and optimisation for flow separation control

Jukes

Choi

2011

Exp Fluids

View full text Add to dashboard Cite

show abstract

“…The contour levels are identical for all three cases. As the jet velocity was increased, dominant streamwise structures developed, as was observed in numerous experimental studies of turbulent VGJ control (Johnston and Nishi 1990, Compton and Johnston 1992, Khan and Johnston 2000. These structures have great potential for enhancing the momentum exchange between the near-wall and outer regions of the flow.…”

Section: Steady Vgjsmentioning

confidence: 77%

“…Johnston and Nishi (1990) considered spanwise arrays of pitched and skewed steady VGJs and reported the formation of streamwise vortices in the boundary layer. Compton and Johnson (1992) investigated the streamwise development of such longitudinal structures and concluded that skew angles of 450 to 900 created the strongest vortices.…”

Section: Vortex Generator Jets (Vgjs) For Active Flow Control (Afc)mentioning

confidence: 99%

Control of Separation for Turbulent Boundary Layers Subjected to Wall Curvature and Streamwise Pressure Gradients

Fasel¹

2005

View full text Add to dashboard Cite

“…By combining MJVGs, various vortex fields can be generated and an array of MJVGs might have similar control effects as ordinary solid-type VGs. Various research has been done on flow control by jets 8,9) and synthetic jets, 10) but the fundamental processes in forming a longitudinal vortex by using multiple jets have not been examined in detail. This paper reports some basic characteristics of MJVG actuators under development.…”

Section: Introductionmentioning

confidence: 99%