Boeing N+2 Supersonic Experimental Validation Phase II Program

Magee, Todd; Fugal, Spencer R.; Fink, Lawrence E.; Shaw, Stephen G.

doi:10.2514/6.2014-2137

Cited by 13 publications

(5 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…NASA contracted Boeing [8,9] and Lockheed Martin [24] to conduct design of N+2 supersonic airplane. Both the designs have good aerodynamic performance, but the sonic boom levels are at about 80-85dBPL [9,10,11], still quite distanced from the targeted 65 to 70 dBPL. Welge et al [8,9] present Boeing's projected supersonic civil transports up to N+3 in 2040, which indicates that their configurations for the next 3 decades will be mostly the same tube-wing configuration with the difference in the details and refinement.…”

Section: Sonic Boommentioning

confidence: 99%

See 1 more Smart Citation

Analysis of a Low Boom Supersonic Flying Wing Preliminary Design

Gan

Zha

2015

53rd AIAA Aerospace Sciences Meeting

View full text Add to dashboard Cite

This paper presents the numerical analysis of a low boom supersonic bi-directional flying wing (SBiDir-FW) preliminary design to demonstrate the advantages of the concept. The mission requirements include cruise Mach number of 1.6, cruise altitude around 50kft, payload of 100 passengers, and a range of 4000nm. The gross takeoff weight is about 197kLb. The configuration is a flying wing symmetric about both the longitudinal and span axes. The sweep angle varies from 82 • at the very leading edge to 78 • at the tip. Two designs with same sweep angles and planform shapes are presented by varying airfoil meanline angle distributions to achieve different overpressure signatures and L/D ratios. The first design D82-78.4 achieves an L/D of 8.16, C L of 0.54, and the ground sonic boom noise level of 71.7PLdB. The second design D82-78.8 increases the C L and L/D with C L =0.60 and L/D = 8.54, while keeping a low level of ground sonic boom at 71.9PLdB by cruising at a little higher altitude of 52kft. A typical near field overpressure signature has a strong shock wave followed by a strong expansion in the overall process of expansion. The strong shockexpansion is mostly canceled out by themselves during the process of the wave propagation to ground. The designs indicate that the overpressure signature and aerodynamic efficiency are very sensitive and controllable by the variation of meanline angle distributions of the airfoils. This is an important relationship between the geometry parameters and the sonic boom/aerodynamic efficiency so that a design optimization strategy can be developed. All the designs with varied meanline angle distributions in this paper are conducted manually. With the encouraging results achieved so far, it is believed that the NASA's N+2 and N+3 goal to have ground sonic boom below 70PLdB for a supersonic civil transport is close to reach if a systematic design optimization is conducted.

show abstract

Section: Sonic Boommentioning

confidence: 99%

“…The aspect ratio increase is hence quite limited. Both the scissor wing and swing wing configurations are not adopted by Boeing and Lockheed Martin for their N+2 and N+3 designs [8,9,10,11,12]. …”

Section: Aerodynamic Efficiencymentioning

confidence: 99%

Analysis of a Low Boom Supersonic Flying Wing Preliminary Design

Gan

Zha

2015

53rd AIAA Aerospace Sciences Meeting

View full text Add to dashboard Cite

show abstract

“…コンコルド以来となる超音速旅客機(SST : Supersonic Transport)として，巡航マッハ数が 1.6 程度の超音速ビジネスジェット機や小型 SST に注目が集まっている [1][2][3][4]…”

Section: 記号の説明unclassified

Performance Evaluation of Compression Ramp for Supersonic Intake in Propulsion/Airframe Integration Design

Miki¹,

Watanabe²,

Kameda³

2015

JOURNAL OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCE

View full text Add to dashboard Cite

Diverter-less intake for supersonic aircraft is examined as a modern design technique of propulsion/airframe integration. In this study, a design guideline for the compression ramp in an external compression supersonic intake mounted on a low diverter or without diverter is examined by CFD analysis. We pursue the optimum configuration of the ramp which minimizes the boundary-layer flowing into intake without failing to decelerate the supersonic flow captured by an intake. The flow field over a single-stage rectangular wedge mounted on a flat surface was investigated under the free stream Mach number of 1.6. The results show that, under a given cross-sectional area of the intake throat, the width and angle of the ramp are important parameters to determine the optimum configuration. In order to decrease the mass flow rate of boundary-layer which flows into an intake, the ramp width should be small as long as the minimum decelerating demand is satisfied. The excessive large angle is not allowed because it induces substantial pressure loss of the main flow. In case of diverter-less configuration, the ramp width should be designed smaller than that in case of configuration with diverter to minimize the incoming boundary-layer.

show abstract

“…Previous work by NASA, such as the Shaped Sonic Boom Demonstrator 1 (SSBD), the Quiet Spike 2 , and the NASA N+2 vehicle studies 3,4 , studied how the sonic boom signatures can be reduced with aircraft shaping. Further work was desired to understand the contribution of the nozzle exhaust plume to the sonic boom signature from the aft portion of a supersonic vehicle.…”

Section: Introductionmentioning

confidence: 99%

Plume and Shock Interaction Effects on Sonic Boom in the 1-foot by 1-foot Supersonic Wind Tunnel

Castner

Elmiligui

Cliff

et al. 2015

53rd AIAA Aerospace Sciences Meeting

View full text Add to dashboard Cite

The desire to reduce or eliminate the operational restrictions of supersonic aircraft over populated areas has led to extensive research at NASA. Restrictions are due to the disturbance of the sonic boom, caused by the coalescence of shock waves formed by the aircraft. A study has been performed focused on reducing the magnitude of the sonic boom N-wave generated by airplane components with a focus on shock waves caused by the exhaust nozzle plume. Testing was completed in the 1-foot by 1-foot supersonic wind tunnel to study the effects of an exhaust nozzle plume and shock wave interaction. The plume and shock interaction study was developed to collect data for computational fluid dynamics (CFD) validation of a nozzle plume passing through the shock generated from the wing or tail of a supersonic vehicle. The wing or tail was simulated with a wedgeshaped shock generator. This test entry was the first of two phases to collect schlieren images and off-body static pressure profiles. Three wedge configurations were tested consisting of strut-mounted wedges of 2.5degrees and 5-degrees. Three propulsion configurations were tested simulating the propulsion pod and aft deck from a low boom vehicle concept, which also provided a trailing edge shock and plume interaction. Findings include how the interaction of the jet plume caused a thickening of the shock generated by the wedge (or aft deck) and demonstrate how the shock location moved with increasing nozzle pressure ratio. Nomenclature D= test nozzle outer diameter, inches NPR = nozzle pressure ratio, Pt / P∞ P = local static pressure, psia Pt = total pressure in nozzle, psia P∞ = free stream static pressure, psia ΔP/P = normalized static pressure, (P -P∞)/ P∞ x = axial distance from jet simulator nozzle exit plane, inches y = vertical distance from nozzle centerline, inches

show abstract

Boeing N+2 Supersonic Experimental Validation Phase II Program

Cited by 13 publications

References 4 publications

Analysis of a Low Boom Supersonic Flying Wing Preliminary Design

Analysis of a Low Boom Supersonic Flying Wing Preliminary Design

Performance Evaluation of Compression Ramp for Supersonic Intake in Propulsion/Airframe Integration Design

Plume and Shock Interaction Effects on Sonic Boom in the 1-foot by 1-foot Supersonic Wind Tunnel

Contact Info

Product

Resources

About