A Multidisciplinary Approach to Mixer-Ejector Analysis and Design

Hendricks, Eric S.; Seidel, Jonathan A.

doi:10.2514/6.2012-4224

Cited by 3 publications

(2 citation statements)

References 4 publications

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“…Another promising technical option to reduce jet noise is the so-called mixer ejector nozzle, which enables the virtual increase of the takeoff bypass ratio by injecting air from outside the engine into the jet through a variable opening to efficiently reduce the jet velocity. Variable mixer ejectors were investigated by NASA [30] and in the EU FP6 project HISAC with an expected benefit of approximately 7 EPNdB. Here, the identified drawback is an increased drag coefficient and extra weight.…”

Section: Sustainable Supersonic Transport: Technical Challenges and Noise Certificationmentioning

confidence: 99%

Future Aircraft and the Future of Aircraft Noise

Knobloch

Manoha

Atinault

et al. 2022

Aviation Noise Impact Management

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In order to cope with increasing air traffic and the requirement to decrease the overall footprint of the aviation sector—making it more sustainably and acceptable for the whole society—drastic technology improvements are required beside all other measures. This includes also the development of novel aircraft configurations and associated technologies which are anticipated to bring significant improvements for fuel burn, gaseous and noise emissions compared to the current state and the current evolutionary development. Several research projects all over the world have been investigating specific technologies to address these goals individually, or novel—sometimes also called “disruptive” —aircraft concepts as a whole. The chapter provides a small glimpse on these activities—mainly from a point of view of recent European funded research activities like Horizon2020 projects ARTEM, PARSIFAL, and SENECA being by no-way complete or exhaustive. The focus of this collection is on noise implications of exemplary novel concepts as this is one of the most complicated and least addressed topics in the assessment of aircraft configurations in an early design stage. Beside the boundary layer ingestion concept, the design process for a blended wing body aircraft is described, a box-wing concept is presented and an outlook on emerging supersonic air transport is given.

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Section: Sustainable Supersonic Transport: Technical Challenges and Noise Certificationmentioning

confidence: 99%

Future Aircraft and the Future of Aircraft Noise

Knobloch

Manoha

Atinault

et al. 2022

Aviation Noise Impact Management

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“…Results showed that the central plug increased the pumping ratio about 60-70% and the total pressure prior to flow entry into circularly lobed nozzle increased about 0.8-1.0% over the same lobed nozzle without a central plug. Besides, some researchers had made investigations on the applications of lobed mixer-ejector [33][34][35][36][37][38]. It is noticed that the above investigations on the mixer-ejector are featured to the straight mixing ducts.…”

Section: Introductionmentioning

confidence: 98%

Parametric Effects on Internal Aerodynamics of Lobed Mixer-Ejector With Curved Mixing Duct

Pan

Shan

Zhang

2014

Journal of Engineering for Gas Turbines and Power

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The internal flow characteristics inside lobed mixer-ejector with curved mixing duct and the parametric effects on the lobed mixer-ejector performance are investigated numerically and validated by experimental test. The cwved mixing duct ajfects the development of the streamwise vortices induced by the lobed mixer. When the mixing process undergoes the transition from the straight section to the bent section, the flow inside the cwved mixing duct is dominated by the impinging and centrifugal ejfects. In general, the pumping ratio is decreased approximately 20%-30% once the bent section is mounted on the straight duct. The mixer-ejector performance could by improved by increasing the straight section length, due to more fully momentum utilization of primary jet and weaker influence of bent section on the back pressure near nozzle exit. The mixer-ejector pumping capacity is also augmented with the increase of mixing duct area ratio until the area ratio is reached to 3.5. And the fully-utilization of primary jet momentum inside mixing duct with big area ratio needs long mixing distance. The pumping ratio is decreased as the increase of bent angle of curved mixing duct in approximately linear relationship. When the bent angle exceeds 45 deg, the thermal mixing efficiency is decreased rapidly as the increase of bent angle.

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