TY  - JOUR
A1  - Götten, Falk
A1  - Havermann, Marc
A1  - Braun, Carsten
A1  - Marino, Matthew
A1  - Bil, Cees
T1  - Airfoil drag at low-to-medium reynolds numbers: A novel estimation method
JF  - AIAA Journal
N2  - This paper presents a novel method for airfoil drag estimation at Reynolds numbers between 4×10⁵ and 4×10⁶. The novel method is based on a systematic study of 40 airfoils applying over 600 numerical simulations and considering natural transition. The influence of the airfoil thickness-to-chord ratio, camber, and freestream Reynolds number on both friction and pressure drag is analyzed in detail. Natural transition significantly affects drag characteristics and leads to distinct drag minima for different Reynolds numbers and thickness-to-chord ratios. The results of the systematic study are used to develop empirical correlations that can accurately predict an airfoil drag at low-lift conditions. The new approach estimates a transition location based on airfoil thickness-to-chord ratio, camber, and Reynolds number. It uses the transition location in a mixed laminar–turbulent skin-friction calculation, and corrects the skin-friction coefficient for separation effects. Pressure drag is estimated separately based on correlations of thickness-to-chord ratio, camber, and Reynolds number. The novel method shows excellent accuracy when compared with wind-tunnel measurements of multiple airfoils. It is easily integrable into existing aircraft design environments and is highly beneficial in the conceptual design stage.
Y1  - 2020
U6  - https://doi.org/10.2514/1.J058983
SN  - 1533-385X
VL  - 58
IS  - 7
SP  - 2791
EP  - 2805
PB  - AIAA
CY  - Reston, Va.
ER  - 
TY  - JOUR
A1  - Götten, Falk
A1  - Havermann, Marc
A1  - Braun, Carsten
A1  - Marino, Matthew
A1  - Bil, Cees
T1  - Aerodynamic Investigations of UAV Sensor Turrets - A Combined Wind-tunnel and CFD Approach
JF  - SciTech 2021, AIAA SciTech Forum, online, WW, Jan 11-15, 2021
Y1  - 2021
U6  - https://doi.org/10.2514/6.2021-1535
SP  - 1
EP  - 12
PB  - AIAA
CY  - Reston, Va.
ER  - 
TY  - CHAP
A1  - Geiben, Benedikt
A1  - Götten, Falk
A1  - Havermann, Marc
T1  - Aerodynamic analysis of a winged sub-orbital spaceplane
N2  - This paper primarily presents an aerodynamic CFD analysis of a winged spaceplane geometry based on the Japanese Space Walker proposal. StarCCM was used to calculate aerodynamic coefficients for a typical space flight trajectory including super-, trans- and subsonic Mach numbers and two angles of attack. Since the solution of the RANS equations in such supersonic flight regimes is still computationally expensive, inviscid Euler simulations can principally lead to a significant reduction in computational effort. The impact on accuracy of aerodynamic properties is further analysed by comparing both methods for different flight regimes up to a Mach number of 4.
Y1  - 2020
U6  - https://doi.org/10.25967/530170
N1  - 69. Deutscher Luft- und Raumfahrtkongress 2020, 1. September 2020 - 3. September 2020, online
PB  - DGLR
CY  - Bonn
ER  - 
TY  - CHAP
A1  - Götten, Falk
A1  - Finger, Felix
A1  - Marino, Matthew
A1  - Bil, Cees
A1  - Havermann, Marc
A1  - Braun, Carsten
T1  - A review of guidelines and best practices for subsonic aerodynamic simulations using RANS CFD
T2  - Asia-Pacific International Symposium on Aerospace Technology (APISAT), At Gold Coast, Australia, 04. - 06. Dezember 2019
Y1  - 2019
SN  - 978-1-925627-40-4
ER  - 
TY  - CHAP
A1  - Götten, Falk
A1  - Finger, Felix
A1  - Havermann, Marc
A1  - Braun, Carsten
A1  - Marino, Matthew
A1  - Bil, Cees
T1  - A highly automated method for simulating airfoil characteristics at low Reynolds number using a RANS - transition approach
T2  - Deutscher Luft- und Raumfahrtkongress - DLRK 2019. Darmstadt, Germany
Y1  - 2019
U6  - https://doi.org/10.25967/490026
SP  - 1
EP  - 14
ER  -