Aerodynamic Interference Analysis
between Propeller/Wing for High
Performance Electric Aircraft Using
FaSTAR-move○Shota Taniguchi (ISAS/JAXA)，
Kanako Yasue (JAXA), Ryota Fukuchi (SUBARU),
Atsushi Shinozuka, Akira Oyama (ISAS/JAXA)

1Electric aircraft

2

Alternative means of transportation- eVTOL aircraft©Airbus

Eco-friendly airplane- Airplane with DEP

©NASA

©NASA

- Airplane with BLI©NASA

Propeller layout for electric aircraft

3

Propeller layout taking advantage of
aerodynamic interference between propeller/wingWingtip mounted propeller

Distributed electric propulsion (DEP)©NASA©AirbusResearch on aerodynamic interference
Wingtip mounted propeller

4Experiments show smaller drag than mid-span mounted configuration.

[Sinnige et al., 2019]

eVTOL with distributed electric propulsion (DEP)
Experiments show complex aerodynamics due to propeller.

[Geuther et al., 2020]

Lack of understanding of how propellers change theaerodynamic characteristics of the fixed-wing.

Objective
 Clarify the mechanism by which propellers change theaerodynamic characteristics of a wing.
 Verify the URANS accuracy of predicting aerodynamic
characteristics of propeller and fixed-wing .
1. Tip-mounted propeller

2. eVTOL with DEP

5

Tip-mounted propeller Analytical model
Tip-mounted

Mid-span mounted- without propeller- without propeller

Flow conditions

6※Same as Sinnige et al., 2019

Reynolds number

𝑅𝑒𝑐 [-]

640,000

Mach number

𝑀 [-]

0.11

Angle of attack

α[deg]

2.0, 6.0

Propeller advance ratio

𝐽 [-]

0.7

Computational settings
Numerical methods
Unsteady RANS using overset meshsolver : FaSTAR MOVE
Governing equations

3D compressible
Navier-Stokes equations

Time integration

LU-SGS

Convection terms

SLAUReconstruction

MUSCL

Turbulence model

SA-noft2

Computational grid
Consists of fixed-wing grid and four propeller blade grids

7Comparison of URANS and experiment

Withoutpropeller

The results of URANS and experimental results arein good agreement.

8

Propeller effect on drag coefficient of wing and nacelle

AOA=2 [degree]

Mid-span mounted

Tip-mounted

Mid-span mounted propeller increases 𝐶𝐷 of wing and nacelle,
while tip-mounted propeller decreases that.

9Propeller effect on drag distribution
Mid-span mounted

10

Tip-mounted∆𝑐𝑑𝑝 = 𝑐𝑑𝑝 − 𝑐𝑑𝑝 𝑤𝑖𝑡ℎ𝑜𝑢𝑡 𝑝𝑟𝑜𝑝𝑒𝑙𝑙𝑒𝑟

 Propeller downwash increases 𝑐𝑑𝑝 .
➡Larger 𝐶𝐷 for mid-span mounted configuration
 Tip-mounted propeller decrease 𝑐𝑑𝑝 of the nacelle.
➡Smaller 𝐶𝐷 for tip-mounted configuration

eVTOL with DEP analytical model

11

Tandem tilt-wing aircraft model

AR [-]
後翼

5.45

前翼

7.96

Reynolds number

𝑅𝑒𝑀𝐴𝐶 [-]

260,000

Mach number

𝑀 [-]

0.044

Flow field obtained by URANS

12Angle of attack is 4 degree

-1.0

𝐶𝑝0.2

Summary13

We conducted URANS for the wingtip-mounted propeller andeVTOL with DEP to clarify the propeller effect and validate
prediction accuracy.
Wingtip-mounted propeller
・There was a good agreement in 𝐶𝐿 , 𝐶𝐷 with the experiment.
・URANS confirmed drag reduction of the wing.

eVTOL with DEP
 With respect to 𝐶𝐿 , there was qualitative agreement on
the propeller effect on the stall with experiment.
 There was a quantitative agreement on the pressure
coefficient with experiment.

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