TY - JOUR A1 - Havermann, Marc A1 - Seiler, F. A1 - Boller, F. A1 - Mangold, P. T1 - Operation of the ISL transonic shock tube in a high subsonic flow regime / Seiler, F. ; Havermann, M. ; Boller, F. ; Mangold, P. ; Takayama K. JF - Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang Y1 - 2005 SN - 978-3-540-22497-6 SP - 307 EP - 312 PB - Springer CY - Berlin ER - TY - JOUR A1 - Götten, Falk A1 - Finger, Felix A1 - Havermann, Marc A1 - Braun, Carsten A1 - Gomez, Francisco A1 - Bill, C. T1 - On the flight performance impact of landing gear drag reduction methods for unmanned air vehicles JF - Deutscher Luft- und Raumfahrtkongress 2018 N2 - The flight performance impact of three different landing gear configurations on a small, fixed-wing UAV is analyzed with a combination of RANS CFD calculations and an incremental flight performance algorithm. A standard fixed landing gear configuration is taken as a baseline, while the influence of retracting the landing gear or applying streamlined fairings is investigated. A retraction leads to a significant parasite drag reduction, while also fairings promise large savings. The increase in lift-to-drag ratio is reduced at high lift coefficients due to the influence of induced drag. All configurations are tested on three different design missions with an incremental flight performance algorithm. A trade-off study is performed using the retracted or faired landing gear's weight increase as a variable. The analysis reveals only small mission performance gains as the aerodynamic improvements are negated by weight penalties. A new workflow for decision-making is presented that allows to estimate if a change in landing gear configuration is beneficial for a small UAV. Y1 - 2018 U6 - http://dx.doi.org/10.25967/480058 PB - DGLR CY - Bonn ER - TY - JOUR A1 - Havermann, Marc A1 - Moeglin, J.-P. T1 - ISL's Research on Systems with Controlled Effects for Non-Lethal Applications / Moeglin, J.-P. ; Havermann, M. et al. JF - Non-lethal options enhancing security and stability : 3rd European Symposium on Non-Lethal Weapons, May 10 - 12, 2005, Ettlingen, Germany / ICT, Fraunhofer-Institut Chemische Technologie; European Working Group Non-Lethal Weapons Y1 - 2005 N1 - European Symposium on Non-Lethal Weapons ; (3 ; 2005.5.10-12 ; Ettlingen); P 35 PB - ICT CY - Pfinztal ER - TY - JOUR A1 - Havermann, Marc A1 - Kainuma, M. A1 - Takayama, K. T1 - Influence of Physical and Geometrical Parameters on Vortex Rings Generated by a Shock Tube / Havermann, M. ; Kainuma, M. ; Takayama, K. JF - Non-lethal options enhancing security and stability : 3rd European Symposium on Non-Lethal Weapons, May 10 - 12, 2005, Ettlingen, Germany / ICT, Fraunhofer-Institut Chemische Technologie; European Working Group Non-Lethal Weapons Y1 - 2005 N1 - European Symposium on Non-Lethal Weapons ; (3 ; 2005.5.10-12 ; Ettlingen); V 24 PB - ICT CY - Pfinztal ER - TY - JOUR A1 - Lettini, Antonio A1 - Havermann, Marc A1 - Guidetti, Marco A1 - Fornaciari, Andrea T1 - Improved functionalities and energy saving potential on mobile machines combining electronics with flow sharing valve and variable displacement pump JF - IFK 7, 7th International Fluid Power Conference, Efficiency through Fluid Power, 7. Internationales Fluidtechnisches Kolloquium, Workshop Proceedings, Vol. 3, Aachen, DE, 22.-24. Mar, 2010 Y1 - 2010 SN - 978-3-940565-92-1 N1 - IFK, 7, Internationales Fluidtechnisches Kolloquium, 7., Aachen, DE, 2010-03-22 - 2010-03-24 SP - 103 EP - 114 PB - - ER - TY - JOUR A1 - Götten, Falk A1 - Havermann, Marc A1 - Braun, Carsten A1 - Marino, Matthew A1 - Bil, Cees T1 - Improved Form Factor for Drag Estimation of Fuselages with Various Cross Sections JF - Journal of Aircraft N2 - The paper presents an aerodynamic investigation of 70 different streamlined bodies with fineness ratios ranging from 2 to 10. The bodies are chosen to idealize both unmanned and small manned aircraft fuselages and feature cross-sectional shapes that vary from circular to quadratic. The study focuses on friction and pressure drag in dependency of the individual body’s fineness ratio and cross section. The drag forces are normalized with the respective body’s wetted area to comply with an empirical drag estimation procedure. Although the friction drag coefficient then stays rather constant for all bodies, their pressure drag coefficients decrease with an increase in fineness ratio. Referring the pressure drag coefficient to the bodies’ cross-sectional areas shows a distinct pressure drag minimum at a fineness ratio of about three. The pressure drag of bodies with a quadratic cross section is generally higher than for bodies of revolution. The results are used to derive an improved form factor that can be employed in a classic empirical drag estimation method. The improved formulation takes both the fineness ratio and cross-sectional shape into account. It shows superior accuracy in estimating streamlined body drag when compared with experimental data and other form factor formulations of the literature. Y1 - 2020 U6 - http://dx.doi.org/10.2514/1.C036032 SN - 1533-3868 SP - 1 EP - 13 PB - AIAA CY - Reston, Va. ER - TY - JOUR A1 - Havermann, Marc A1 - Salve, M. de A1 - Tin, G. del A1 - Panella, B. T1 - Experimental Study of the Temperature Field along a Density Lock / Salve, M. de ; Tin, G. del ; Panella, B. ; Sansoldo, D. ; Havermann, M. JF - Proceedings : International Conference on New Trends in Nuclear System Thermohydraulics, May 30th - June 2nd, 1994, Pisa / organized by Dipartimento di Costruzioni Meccaniche e Nucleari ... . Ed. by Francesco Oriolo Y1 - 1994 N1 - International Conference on New Trends in Nuclear System Thermohydraulics ; (1994.05.30-06.02 ; Pisa) SP - 623 EP - 630 PB - - CY - Pisa ER - TY - JOUR A1 - Havermann, Marc A1 - Seiler, F. A1 - George, A. A1 - Leopold, F. T1 - Enhanced Doppler Picture Velocimetry (DPV) for Planar Velocity Measurements in High-Speed Shock Tunnel Flow / Seiler, F. ; George, A. ; Leopold, F. ; Havermann, M. ; Srulijes, J. JF - 10th International Symposium on Flow Visualization : Kyōto, Japan, August 26 - 29, 2002 / sponsored by International Flow Visualization Society . [Chairman:] Toshio Kobayashi Y1 - 2002 SN - 4906497829 N1 - International Symposium on Flow Visualization ; (10 ; 2002.08.26-29 ; Kyōto) PB - Visualization Society of Japan CY - Kyoto ER - TY - JOUR A1 - Havermann, Marc T1 - Effects of the shock tube open-end shape on vortex loops released from it / Kainuma, M. ; Havermann, M. ; Sun, M. ; Takayama, K. JF - Shock Waves : Proceedings of the 24th International Symposium on Shock Waves Beijing, China July 11-16, 2004 / edited by Z. Jiang Y1 - 2005 SN - 978-3-540-22497-6 SP - 505 EP - 510 PB - Springer CY - Berlin ER - TY - JOUR A1 - Pichler, A. A1 - George, A. A1 - Seiler, F. A1 - Srulijes, J. A1 - Havermann, Marc T1 - Doppler Picture Velocimetry (DPV) applied to hypersonics JF - Shock Waves [Elektronische Ressource] : 26th International Symposium on Shock Waves, Volume 1 / edited by Klaus Hannemann, Friedrich Seiler Y1 - 2009 SN - 978-3-540-85168-4 N1 - International Symposium on Shock Waves ; (26 ; 2007.07.15-20 ; Göttingen) ; ISSW ; (26 ; 2007.07.15-20 ; Göttingen) SP - 503 EP - 508 PB - Springer CY - Berlin ER -