Noise of a model high speed counterrotation propeller at simulated takeoff/approach conditions (F7/A7)

Woodward, Richard P.

doi:10.2514/6.1987-2657

Cited by 31 publications

(31 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While turbofan engines have been the most commonly used aircraft engines since the early 1950s, as a result of the increased fuel prices of the 1970s, the development of other economically feasible propulsion technologies has been investigated [1]. Due to its superior propulsive efficiency, one of the main contenders as an alternative to the currently used turbofan technology is the Counter-Rotating Open Rotor (CROR) [1,2]. Applying them on certain categories of aircraft would lead to a considerable reduction in fuel consumption.…”

Section: Introductionmentioning

confidence: 99%

Investigation of a Pylons Effect on the Character of Counter-Rotating Open Rotor Noise Using Beamforming Technology

Fenyvesi¹,

Tokaji²,

Horváth³

2019

Acta Acustica united with Acustica

View full text Add to dashboard Cite

Phased array microphones and beamforming technology are applied herein in order to better understand the noise sources associated with the installation effects of a counter-rotating open rotor propulsion system. The study compares an installed (equipped with a pylon) and an uninstalled (standalone) engine for takeoff nominal flight conditions, using beamforming results to investigate the far-field acoustic character and to localize noise sources, sorting them into various components accordingly. The study demonstrates how the various noise sources falling in the blade passing frequency bins can be separated into those components which are truly associated with the blade passing frequency and those which are associated with blade-wake interactions. This is done by taking into consideration the nature of the noise sources, and distinguishing between rotating coherent and stationary coherent noise sources. The paper also demonstrates that the impact of the pylon wake on the rotating coherent noise sources (such as blade passing frequency tones and interaction tones) and on the rotating incoherent noise sources (such as rotating broadband noise sources and shaft order noise sources) is small. Though the paper presents the results of a specific comparison, the methodology for separating apart the various components noise presented herein is generally applicable in other investigations.

show abstract

Section: Introductionmentioning

confidence: 99%

Investigation of a Pylons Effect on the Character of Counter-Rotating Open Rotor Noise Using Beamforming Technology

Fenyvesi¹,

Tokaji²,

Horváth³

2019

Acta Acustica united with Acustica

View full text Add to dashboard Cite

show abstract

“…The prominence of self-noise over interaction noise depends on the flight condition [2,3]; self-noise is largely dominating at cruise condition, whereas interaction noise is significant if not dominant at takeoff condition.…”

Section: Introductionmentioning

confidence: 99%

Influence of Torque Ratio on Counter-Rotating Open-Rotor Interaction Noise

Delattre

Falissard

2015

AIAA Journal

View full text Add to dashboard Cite

This paper investigates the influence of the torque ratio, at constant total thrust, on the interaction noise of a generic counter-rotating open rotor in pusher configuration. It is shown that torque ratio has a small influence on the openrotor aerodynamic performance but a strong impact on interaction noise at takeoff condition. The noise source mechanisms are investigated in detail and linked with the characteristics of the front rotor blade-tip vortices. Tip vortex characteristics are detailed and compared with analytical vortex models. It is verified that torque ratio variation has no strong impact on the open-rotor aerodynamic performance at cruise condition.

show abstract

“…In the 1980's, this effect was documented with an earlier set of blades. The same 2-forward blade count plus 1-aft blade count shaft order tone was found to be most sensitive to rotor spacing, see Figure 16 of [19].…”

Section: Figure 7 Effect Of Aft Rotor Phase On Inter-rotor Velocity mentioning

confidence: 83%

Effect of Aft Rotor on the Inter-Rotor Flow of an Open Rotor Propulsion System

Slaboch

Stephens

Zante

et al. 2016

Journal of Engineering for Gas Turbines and Power

View full text Add to dashboard Cite

The effects of the aft rotor on the inter-rotor flow field of an open rotor propulsion rig were examined. A Particle Image Velocimetry (PIV) dataset that was acquired phase locked to the front rotor position has been phase averaged based on the relative phase angle between the forward and aft rotors. The aft rotor phase was determined by feature tracking in raw PIV images through an image processing algorithm. The effects of the aft rotor potential field on the inter-rotor flow were analyzed and shown to be in reasonably good agreement with Computational Fluid Dynamics (CFD) simulations. The aft rotor position was shown to have a significant upstream effect, with implications for front rotor interaction noise. It was found that the aft rotor had no substantial effect on the position of the forward rotor tip vortex but did have a small effect on the circulation strength of the vortex when the rotors were highly loaded.

show abstract

Noise of a model high speed counterrotation propeller at simulated takeoff/approach conditions (F7/A7)

Cited by 31 publications

References 1 publication

Investigation of a Pylons Effect on the Character of Counter-Rotating Open Rotor Noise Using Beamforming Technology

Investigation of a Pylons Effect on the Character of Counter-Rotating Open Rotor Noise Using Beamforming Technology

Influence of Torque Ratio on Counter-Rotating Open-Rotor Interaction Noise

Effect of Aft Rotor on the Inter-Rotor Flow of an Open Rotor Propulsion System

Contact Info

Product

Resources

About