Mitigation of Pusher-Propeller Installation Effects by Pylon Trailing-Edge Blowing

Sinnige, Tomas; Ragni, Daniele; Eitelberg, G.; Veldhuis, L.L.M.

doi:10.2514/1.c034000

Cited by 10 publications

(13 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among the possible flow-control strategies, the active technique of pylon blowing has shown to successfully eliminate the noise penalty due to the wake-impingement effects in various experimental 4-6, 8, 9 and numerical 7,10 studies. The work by Sinnige et al 9 confirmed that the achieved noise reductions are due to the abatement of the unsteady blade-load fluctuations, which is a direct result of the improved uniformity of the propeller inflow with blowing enabled.…”

Section: Introductionmentioning

confidence: 94%

“…11 For the latter, the short mixing length available between the trailing edge of the pylon and the propeller causes wake profiles characterized by a velocity overshoot on the wake centerline with velocity deficits on both sides. 9 The chordwise blowing approach, on the other hand, provides increased mixing length, and thinner boundary layers at the positions of the blowing slots. Experiments have shown that a high degree of uniformity of the pylon wake can be achieved using the chordwise blowing approach.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical Analysis of Pylon-Blowing Systems for Pusher-Propeller Applications

Jindal

Sinnige

Hulshoff

et al. 2017

35th AIAA Applied Aerodynamics Conference

Self Cite

View full text Add to dashboard Cite

Pylon-blowing systems provide an effective way of minimizing the interaction effects due to pylon-wake impingement experienced by pusher propellers. This paper presents a numerical study of the uniformity of the blown pylon wake as a function of blowing-slot geometry and blowing momentum coefficient. The flow around the pylon was simulated by solving the steady-state Reynolds-averaged Navier-Stokes equations. The numerical setup was validated using experimental data for both trailing-edge blowing and chordwise blowing configurations. If experimental error is neglected, the model error for the chordwise blowing layout was 15-17%. It was shown that maximal wake uniformity was achieved for a chordwise blowing configuration with the blowing slots positioned at x/c = 0.7. This location provided the best compromise between boundary-layer thickness upstream of the blowing slot, available mixing length, and boundary-layer development downstream of the slot. The corresponding optimal blowing coefficient resulted in a slight velocity overshoot in the boundary layer at the pylon trailing edge. This overshoot then mixed with the deficit associated with the boundary layer formed downstream of the blowing slot to arrive at a nearly uniform velocity profile in the pylon wake. Under asymmetric inflow conditions, the chordwise blowing approach provided effective wake filling if the blowing coefficients on upper and lower surfaces were separately matched with the local boundary-layer thickness at the blowing slot. A linear relation between required blowing rate and boundary-layer thickness was found. Following this approach, the resulting wake was made nearly uniform at an angle of attack of 9 • .

show abstract

Section: Introductionmentioning

confidence: 94%

Section: Introductionmentioning

confidence: 99%

Numerical Analysis of Pylon-Blowing Systems for Pusher-Propeller Applications

Jindal

Sinnige

Hulshoff

et al. 2017

35th AIAA Applied Aerodynamics Conference

Self Cite

View full text Add to dashboard Cite

show abstract

“…More details about this experiments can be found in the Refs. [3,4]. The test combined several objectives into one experiment, such that several test and measurement techniques were combined.…”

Section: Project#2 For the Llf Wind Tunnel: New Mexico Wind Turbine Imentioning

confidence: 99%

ESWIRP: European Strategic Wind tunnels Improved Research Potential program overview

Boyet

2018

CEAS Aeronaut J

View full text Add to dashboard Cite

aiming at improving the performance capabilities of three strategic wind tunnels in Europe, by strengthening the cooperation between these wind tunnels in a new consortium. The research consortium members are Office National d'Etudes et de Recherches Aérospatiales (operating the S1MA as its largest sonic wind tunnel), German-Dutch wind tunnels [operating the large low-speed facility (LLF) as its largest low-speed wind tunnel], and European transonic wind tunnel (ETW) (operating its cryogenic wind tunnel). Together, these wind tunnels cover a wide range of experimental capabilities of relevance to civil aviation and aeronautical research in general. The project started in October 2009 for a period of 5 years. The European financial contribution was €7.2 million. The project consist of two major parts: (1) improvements to the testing infrastructure; and (2) the provision of wind tunnel access to research groups which do not usually have the means to access such large-scale test facilities. These topics also involved public dissemination and information activities. Although the tunnels covered in this project are of a complementary nature, the infrastructure activities were joined together, by a common representation of, and approach to, the tunnel performance characteristics. To this end, a generic model of a virtual wind tunnel was developed, enabling operators to assess the effect of the control parameters upon the testing conditions. The final aim of all participants was to provide the user community with an improved set of capabilities to test their innovative ideas. To provide better access to these three major wind tunnels, mainly research groups from European universities were contacted. The approach taken has included maximum transparency of the process and support of the researchers by the organizations responsible for the tunnels. In addition, when possible, we encouraged research groups to work together, to obtain the full benefit of economies of scale in research projects. ESWIRP responded to the targeted approach of the Integrating Activities of the FP7 Capacities Work Program: Networking activities, essentially focused around four topics: (1) organization of information campaigns, lectures and workshops to disseminate knowledge between the partners and future users. (2) Opening of a website for the consultation of wind tunnel standards. (3) Exchange of personnel between the Consortium partners, to foster the spread of good practices and the exchange of technical know-how. (4) Joint development of a reference wind tunnel parameter database. Trans-national access and/or testing services: after the call for proposals by the facility providers, groups of researchers had the opportunity to benefit from free wind tunnel services, including technical assistance to support the corresponding scientific research team(s). Joint research activities, innovative modeling of wind tunnels has helped designers to make better decisions, before the implementation of any novel hardware. Based on a generic finite volume t...

show abstract

“…The NACA 0010 cross section was modified to obtain a trailing-edge thickness of 0.008c. This was required to fit a blowing system into the aft part of the model [23]. The current paper only discusses results obtained without application of the blowing system.…”

Section: Methodsmentioning

confidence: 99%

APIAN-INF: an aerodynamic and aeroacoustic investigation of pylon-interaction effects for pusher propellers

et al. 2017

Self Cite

View full text Add to dashboard Cite

Advanced propellers promise significant fuelburn savings compared to turbofans. When installed on the fuselage in a pusher configuration, the propeller interacts with the wake of the supporting pylon. This paper presents an experimental analysis of the aerodynamic and aeroacoustic characteristics of this pylon-propeller interaction. An isolated propeller was operated in undisturbed flow and in the wake of an upstream pylon at the large low-speed facility of the German-Dutch wind tunnels (DNW-LLF). Measurements of the pylon-wake characteristics showed that the wake width and velocity deficit decreased with increasing thrust due to the suction of the propeller. The installation of the pylon led to a tonal noise penalty of up to 24 dB, resulting from the periodic blade-loading fluctuations caused by the wake encounter. The noise penalty peaked in the upstream direction and became increasingly prominent with decreasing propeller thrust setting, due to the associated reduction of the steady blade loads. The integral propeller performance was not significantly altered by the pylon-wake encounter process. However, at sideslip angles of ±6°, the effective advance ratio of the propeller was modified by the circumferential velocity components induced by the pylon tip vortex. The propeller performance improved when the direction of rotation of the propeller was opposite to that of the pylon tip vortex. Under this condition, a reduction was measured in the noise emissions due to a favorable superposition of the angular-inflow and pylon-wake effects.Keywords Propulsion integration Á Pusher propellers Á Propeller noise Á Pylon-installation effects List of symbols BNumber of blades

show abstract

Mitigation of Pusher-Propeller Installation Effects by Pylon Trailing-Edge Blowing

Cited by 10 publications

References 13 publications

Numerical Analysis of Pylon-Blowing Systems for Pusher-Propeller Applications

Numerical Analysis of Pylon-Blowing Systems for Pusher-Propeller Applications

ESWIRP: European Strategic Wind tunnels Improved Research Potential program overview

APIAN-INF: an aerodynamic and aeroacoustic investigation of pylon-interaction effects for pusher propellers

Contact Info

Product

Resources

About