Engine Integration of the Flying V

Engine Integration of the Flying V: Quantification of Engine Integration Effects using Wind Tunnel Experiments

van Empelen, Sjoerd (TU Delft Aerospace Engineering)

Vos, Roelof (mentor)
Veldhuis, Leo (graduation committee)
Timmer, Nando (graduation committee)

Delft University of Technology

Aerospace Engineering

2020-06-02

An experimental investigation was done regarding the propulsion system and airframe integration issues associated with the novel Flying V configuration. The experimental investigations involved a series of wind tunnel tests with a 4.6% scale half model, conducted in the TU Delft OJF low speed wind tunnel. Balance measurements allowed significant interference effects between the wing and engine to be identified. A nacelle mounted total pressure rake enabled the measurement of engine inlet total pressure, both in through-flow nacelle and powered conditions. At landing and take-off velocity (20m/s), an interference drag penalty is observed over the full range of positive incidence angles above 5 degrees, with a maximum of 60 counts (16.5% of isolated wing drag) at an incidence angle of 10 degrees. At incidence angles lower than 5∘ engine operation is somewhat beneficial, with a maximum contribution to thrust due to interference of approximately 20 counts. Engine inflow is shown to be distorted by the presence of the wing, which could contribute to the observed interference drag. Distortion DC(60) values higher than 0.2 are measured in off design conditions, while measurements at cruise condition show a DC(60) value of 0.08. However, distinguishing between loss of engine thrust and increase in airframe drag is not possible with the used setup. Increased suction around the engine intake contributes to added lift and nose down pitching moment at high thrust setpoints and incidence angles between 5 degrees and 12.5 degrees. An increase in nose up pitching moment is observed from 12.5 degrees to 22.5 degrees. To put the measured interference in perspective, the direct effects of the quantified interference on trimmed flight conditions are demonstrated. An increased power requirement of up to +8% is observed in trimmed flight conditions between 22m/s and 31m/s, while a maximum reduction of -11% in power requirement is predicted for velocities higher than 32m/s. The change in required control surface deflection for trim due to engine interference is evaluated to be less than +/ − 2.5 degrees for trimmed level flight. A trimmable flight envelope is demonstrated for maximum climb, level flight and optimum glide with control surface deflections in the range of −10 to 10 degrees.

Flying V
Engine
Interference
Wind Tunnel Experiment
Flight characteristics
flying wing
Stability Analysis

http://resolver.tudelft.nl/uuid:c519caf8-0eba-4633-a4f9-be37684417a8

Student theses

master thesis

© 2020 Sjoerd van Empelen