Forced mixer lobes in ejector designs

Presz, Walter M.; Morin, Bruce Kl.; Gousy, Robert G.

doi:10.2514/3.23073

Cited by 74 publications

(26 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Then they made further investigation on the applications of lobed mixerejector in noise suppression and thrust augment [27,28]. Skebe et al [29] and Presz et al [6] made experimental investigations of the effects of geometric and operating parameter variations, such as the lobe penetration angel and height, the mixing duct diameter and length, the diffuser expand angle, pressure ratio, etc., on the mixer-ejector pumping performance of a representative low pressure ratio jet engine exhaust system. Their results suggested guidelines for designing mixer-ejector geometries to achieve optimum pumping efficiency.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

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

View full text Add to dashboard Cite

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.

show abstract

Section: Introductionmentioning

confidence: 99%

“…In short efficient mixer-ejector systems, the primary nozzle plays an important role on the pumping and mixing capacities. The lobed nozzle is illustrated to be one of the best choices [5,6].…”

Section: Introductionmentioning

confidence: 99%

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

View full text Add to dashboard Cite

show abstract

“…The enhanced mixing of the lobed mixers is believed to be directly attributable to the large mixing scales generated by the streamwise vortices. Application of lobed mixers in the turbofan engine exhausts has been studied by Presz, Blinn and Morin [1J and Presz, Gousy and Morin [2], where the rapid mixing of the core and the bypass flows can achieve noise reduction and thrust enhancement. Paterson [3] measured velocity and turbulence characteristics downstream of a lobed mixer using laserDoppler anemometer and concluded that both the lobe shape and lobe penetration were the important parameters to determine the effectiveness of mixer performances.…”

Section: Introductionmentioning

confidence: 99%

Computational studies of lobed forced mixer flows

1998

J. of Therm. Sci.

View full text Add to dashboard Cite

Full Navier Stokes Analyses have been conducted for the flows behind the trailing edge of a lobed forced mixer. The governing equations are derived from the time-dependent compressible Navier-Stokes equations and discretized in the finite-difference form. A simple two-layer eddy viscosity model has also been used to account for the turbulence. Computed results are compared with some of the velocity measurements using a laser-Doppler anemometer (Yu and Yip (1997)). In general, good agreement can be obtained in the streamwise mean velocity distribution but the decay of the streamwise circulation is underpredicted. Some suggestions to the discrepancy are proposed.

show abstract

“…Ventilation air is therefore required to keep the nacelle and engine wall surface temperatures at acceptable levels. One means of providing this ventilation air is an exhaust ejector [1][2][3][4].…”

Section: Introductionmentioning

confidence: 99%

Investigations of flows in a new infrared suppressor

Suo-fang

2006

Applied Thermal Engineering

View full text Add to dashboard Cite

Forced mixer lobes in ejector designs

Cited by 74 publications

References 5 publications

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

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

Computational studies of lobed forced mixer flows

Investigations of flows in a new infrared suppressor

Contact Info

Product

Resources

About