@misc{DueckershoffBiesoldBerg, author = {D{\"u}ckershoff, Roland and Biesold, Volker and Berg, Heinz Peter}, title = {Einsatz der Laser Patricle Image Velocimetry und der Ammoniak-Diazo-Messtechnik bei der Entwicklung moderner Hochdruckturbinen mit lokalem Druckaufbau und zeitlich begrenzter Str{\"o}mungsabl{\"o}sung}, language = {de} } @inproceedings{FeilerBerg, author = {Feiler, Christoph and Berg, Heinz Peter}, title = {Str{\"o}mungsfeldvermessung und W{\"a}rme{\"u}bergangsmessung an Reynolds-{\"a}hnlichen Turbinenkaskaden}, series = {Motto: Luft- und Raumfahrt - Schmelztiegel der Disziplinen, Deutscher Luft- und Raumfahrtkongress 2002, Stuttgart, 23. bis 26. September 2002, Bd. 3}, booktitle = {Motto: Luft- und Raumfahrt - Schmelztiegel der Disziplinen, Deutscher Luft- und Raumfahrtkongress 2002, Stuttgart, 23. bis 26. September 2002, Bd. 3}, publisher = {DGLR}, address = {Bonn}, pages = {1821 -- 1831}, language = {de} } @inproceedings{BergAntoshkivChenetal., author = {Berg, Heinz Peter and Antoshkiv, Oleksiy and Chen, X.-M. and Liu, F.}, title = {Einsatz von neuartigen Entwicklungswerkzeugen bei der Brennraumgestaltung von Flugmotoren}, series = {Motto: Luft- und Raumfahrt - Schmelztiegel der Disziplinen, Deutscher Luft- und Raumfahrtkongress 2002, Stuttgart, 23. bis 26. September 2002, Bd. 2}, booktitle = {Motto: Luft- und Raumfahrt - Schmelztiegel der Disziplinen, Deutscher Luft- und Raumfahrtkongress 2002, Stuttgart, 23. bis 26. September 2002, Bd. 2}, publisher = {DGLR}, address = {Bonn}, pages = {1499 -- 1506}, language = {de} } @article{ChenLiuBerg, author = {Chen, X.-M. and Liu, Fushui and Berg, Heinz Peter}, title = {Untersuchung der Zylinderinnenstr{\"o}mung an einen BDE - Motor mittels Laser - PIV}, language = {de} } @article{ChenBergKeil, author = {Chen, X. and Berg, Heinz Peter and Keil, M.}, title = {Flexible dynamische Messdatenerfassung an einem Motorpr{\"u}fstand}, language = {de} } @inproceedings{AhlinderBergReile, author = {Ahlinder, Stefan and Berg, Heinz Peter and Reile, E.}, title = {Modelling of compact tube bundle heat exchanger as porous medium using Reynold´s anallgy}, abstract = {Numerische Untersuchung der Str{\"o}mung und der W{\"a}rme{\"u}bertragung in einem kompakten Rohrb{\"u}ndel-W{\"a}rmetauscher, der als por{\"o}ses Medium modelliert ist.}, language = {en} } @inproceedings{AntoshkivKruegerSarradjetal., author = {Antoshkiv, Oleksiy and Kr{\"u}ger, Falko and Sarradj, Ennes and Berg, Heinz Peter}, title = {Acoustical Diagnostic of Spray-Airflow Interaction in a Modern Aero Engine Combustor Chamber}, series = {Deutscher Luft- und Raumfahrtkongress 2009, Bd. Manuskripte}, booktitle = {Deutscher Luft- und Raumfahrtkongress 2009, Bd. Manuskripte}, publisher = {DGLR}, address = {Bonn}, isbn = {978-3-932182-64-8}, language = {en} } @inproceedings{DueckershoffBiesoldBerg, author = {D{\"u}ckershoff, Roland and Biesold, Volker and Berg, Heinz Peter}, title = {Filmk{\"u}hlung bei verz{\"o}gerter Hauptstr{\"o}mung und lokaler Str{\"o}mungsabl{\"o}sung}, series = {Motto: Luft- und Raumfahrt - Made in Germany, Deutsche Technologie im internationalen Wettbewerb, Deutscher Luft- und Raumfahrtkongress 2001, Hamburg, 17. - 20. September 2001, Bd. 3}, booktitle = {Motto: Luft- und Raumfahrt - Made in Germany, Deutsche Technologie im internationalen Wettbewerb, Deutscher Luft- und Raumfahrtkongress 2001, Hamburg, 17. - 20. September 2001, Bd. 3}, publisher = {DGLR}, address = {Bonn}, pages = {1715 -- 1720}, language = {de} } @article{DueckershoffBiesoldBerg, author = {D{\"u}ckershoff, Roland and Biesold, Volker and Berg, Heinz Peter}, title = {Einsatz der Laser-Patricle-Image Velocimetry und der Ammoniak-Diazo-Messtechnik zur Untersuchung der Filmk{\"u}hlung zuk{\"u}nftiger Hochdruckturbinen}, language = {de} } @inproceedings{BergMalenkyAntoshkivetal., author = {Berg, Heinz Peter and Malenky, Uwe and Antoshkiv, Oleksiy and Mattke, Robert}, title = {Kompakte hocheffektive Mikrogasturbine mit integriertem Generator (MTIG): eine Komponente f{\"u}r die seriellen hybriden Antriebssysteme der Elektroflugzeuge von morgen}, series = {Deutscher Luft- und Raumfahrtkongress 2015 Rostock}, booktitle = {Deutscher Luft- und Raumfahrtkongress 2015 Rostock}, publisher = {Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, address = {Bonn}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-20151109556}, pages = {9}, abstract = {Bei der Neugestaltung unserer zuk{\"u}nftigen Lebensr{\"a}ume sucht die Forschung nach neuartigen L{\"o}sungen f{\"u}r die bodengebundene Mobilit{\"a}t. Weiterhin spielt die Erforschung umweltvertr{\"a}glicher Antriebstechnologien f{\"u}r die Luftfahrt der Zukunft eine wichtige Rolle. Neben den rein elektrischen Antrieben stehen insbesondere fortschrittliche hybride Antriebssysteme im Vordergrund. Systeml{\"o}sungen werden kurz- bis mittelfristig f{\"u}r die unbemannten Flugzeuge und die allgemeine Luftfahrt ben{\"o}tigt. Es werden effiziente Flugantriebssysteme ben{\"o}tigt, die gegen{\"u}ber aktuellen Antriebssystemen deutlich weniger Schadstoffe emittieren und Brennstoff-ressourcen schonen. Dabei bietet der Elektroantrieb ein großes Potenzial. Aufgrund des derzeitig ung{\"u}nsti-gen Verh{\"a}ltnisses zwischen Gewicht und Energieinhalt bei Traktionsbatterien ist jedoch die rein elektrische Flugweise nur f{\"u}r einen sehr kleinen Anwendungsbereich interessant. Deshalb m{\"u}ssen Elektroluftfahrzeuge mit zus{\"a}tzlichen Energiewandlern und Speichern ausgestattet werden, um akzeptable Reichweiten und An-triebsleistungen bei moderaten Kosten zu gew{\"a}hrleisten. Als zukunftsf{\"a}higes Antriebskonzept wird u.a. das hybride elektrische Antriebssystem mit Kleinenergieerzeugern zur Reichweitenverl{\"a}ngerung angesehen. F{\"u}r den Einsatz als Range-Extender stehen unterschiedliche Konzepte zur Verf{\"u}gung, die eine Umwandlung von chemischer in elektrische Energie erm{\"o}glichen. Die Spezifikation eines Range-Extenders h{\"a}ngt dabei sehr stark von den Anforderungen an zuk{\"u}nftige Antriebskonzepte ab. Das bedeutet, dass Einbauraum, Gewicht, Kosten und Vielstofftauglichkeit eine neu zu definierende Gewichtung im Auswahlprozess des Energiewand-lers erhalten. Schwerpunkt des Beitrages ist die Entwicklung und Applikation eines alternativen Energieum-wandlungskonzeptes f{\"u}r E-Luftfahrzeuge traditioneller Bauweise (z.B. zur Verl{\"a}ngerung der Reichweite bei E-Kleinflugzeugen) und f{\"u}r innovative Luftfahrzeuge (als systemintegraler Bestandteil). Bei diesem Konzept handelt es sich um eine Mikrogasturbinen-Generator-Einheit, welche durch einen Rekuperator (W{\"a}rmetau-scher zur Abgasw{\"a}rmenutzung) einen hohen Wirkungsgrad erm{\"o}glicht und durch eine weitere Prozesshybri-disierung (z.B. mit eingebetteter SOFC) auch f{\"u}r nicht luftfahrttechnische Bereiche interessant ist. Es werden die Mikrogasturbinen-Generator (MTG)-Basistechnologie beschrieben und die Leistung, der Wirkungsgrad und die Vielstofff{\"a}higkeit diskutiert. Außerdem wird eine kompakte Abwandlung mit integriertem Generator (sogenannte MTiG) dargestellt. Weiterhin wird die Bedeutung der Mikrogasturbinenbauart f{\"u}r ein zuk{\"u}nftiges MTG/MTiG-SOFC-Hochwirkungsgradsystem erkl{\"a}rt und die hohe luftfahrttechnische Tauglichkeit der kom-pakten, rekuperierten MTiG-Mikrogasturbinentechnologie f{\"u}r die seriellen hybriden Flugtriebwerkssysteme aufgezeigt.}, language = {de} } @inproceedings{PrechavutBerg, author = {Prechavut, Nontavut and Berg, Heinz Peter}, title = {An Experimental Study on Structural Characteristics of Cantilever-Type Foil Bearings}, series = {Deutscher Luft- und Raumfahrtkongress 2015}, booktitle = {Deutscher Luft- und Raumfahrtkongress 2015}, publisher = {Deutsche Gesellschaft f{\"u}r Luft- und Raumfahrt - Lilienthal-Oberth e.V.}, address = {Bonn}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-201511275091}, abstract = {Capable of high-speed and high-temperature operation, together with an "oil-free" technology concept, gas foil bearings are a perfect solution for a novel light weight (small scale) turbo machinery. While the gas film geometry and the pressure build-up are similar to other gas lubricated bearings, and as it has been well formulated in the hydrodynamic lubrication theory, the compliant structure of the foil bearings have a variety of forms and characteristics. The cantilever-type of foil bearings are one sort of foil bearings that uses a pattern of small cantilever beams as support structure which is very robust and eases the manufacturing process. The aim of this paper is to present a measurement method and results of structural stiffness and damping characteristics of exemplary 50 mm tree-lobes radial foil bearings. Static structural test result shows that the bearing has a wide range of linear stiffness in the bearing's center area. The ramp of cartridge inner surface contour causes a cross coupling effect which may cause instability by a large rotor orbit. Increasing in bear - ing preload result in slightly increasing in static stiffness. In dynamic excitation test, the result shows that the dynamic stiffness is about three times higher than the static one. With a simple model of dry friction, the result shows that the dry friction coefficient is in a range of 0.4 to 0.7. The result also shows that the dynamic stiffness is more sensitive to vibration amplitude than frequency. While the damping decreases significantly with exciting frequency, especially at the vicinity of the rigid body resonance. The result evidence that the magnitude of displacement has a great effect on damping. As displacement amplitude decreases, the bearing is better in damping.}, language = {en} } @misc{MardiKolurAntoshkivBerg, author = {Mardi Kolur, Mohsen and Antoshkiv, Oleksiy and Berg, Heinz Peter}, title = {Experimental analysis of the effect of nano-metals and novel organic additives on performance and emissions of a diesel engine}, series = {Fuel Processing Technology}, volume = {196}, journal = {Fuel Processing Technology}, issn = {0378-3820}, doi = {10.1016/j.fuproc.2019.106166}, pages = {1 -- 10}, abstract = {The present study focuses on performance and emission characteristics of three emulsion fuels with different additives on a single cylinder CI engine. Each of these emulsified fuels is distinctively engineered to be an alternative fuel for diesel engines. The test fuels are diesel, biodiesel, an emulsion fuel with 86\% biodiesel, 5\% DEE, 3\% Ethanol, 50 ppm CNT, 2\% Water, 2\% Tween 80 and 2\% Span 80 (BD.CNT.DEE.E), an emulsion fuel with 86\% biodiesel, 5\% EHN, 3\% Methanol, 50 ppm Al2O3, 2\% Water, 2\% Tween 80 and 2\% Span 80 (BD.ALO.EHN.M) and an emulsion fuel with 86\% biodiesel, 5\% Glycerine, 3\% Butanol, 50 ppm TiO2, 2\% Water, 2\% Tween 80 and 2\% Span 80 (BD.TIO.GLC.B). Experimental results revealed that BD.CNT.DEE.E has significant improvement compared to diesel and biodiesel in every aspect of performance such as enhanced brake power and brake thermal efficiency by 8.1\% and 4.5\%, respectively along with the most BSFC reduction by 4\%. It also shows exceptional reduction in all emissions compared to biodiesel by 26\%, 7.5\%, 9.2\% and 36\% in CO, UHC, NOx and smoke, respectively. BD.ALO.EHN.M also shows considerable improvement in performance including the highest brake thermal efficiency with 6\% increment and decline in all emissions except UHC, compared to biodiesel. Finally, BD.TIO.GLC.B shows a slight drop in performance with 6.6\% drop in brake thermal efficiency, but on the other hand it has the lowest smoke opacity by a plummet of 74.3\%, 20\% decline in CO and 10.7\% reduction in NOx compared to biodiesel. Therefore, it can be deducted that the emulsion fuels with the proper additives including oxygenated fuels, nano metals, stabilizers, cetane improvers and mixture emulsifiers could ensure clean and renewable alternatives for diesel engines.}, language = {de} } @misc{BergHimmelbergPoojitganont, author = {Berg, Heinz Peter and Himmelberg, Axel and Poojitganont, Thanapol}, title = {Hybrid Turbo Compound Fan Engine an Eco-Efficient Propulsion System for Aviation}, series = {Materials Science and Engineering : Thai Society of Mechanical Engineering, the 10th International Conference on Mechanical Engineering (TSME-ICOME2019) 10-13 December 2019, Pattaya, Thailand}, volume = {2020}, journal = {Materials Science and Engineering : Thai Society of Mechanical Engineering, the 10th International Conference on Mechanical Engineering (TSME-ICOME2019) 10-13 December 2019, Pattaya, Thailand}, edition = {1. Auflage}, publisher = {IOP Science}, address = {Bristol}, issn = {1757-899X}, doi = {10.1088/1757-899X/886/1/012010}, pages = {12}, abstract = {The path to electric propulsion systems depends on the development of powerful, compact and very light energy storage system with a high storage density. In order to create an environment-friendly intermediate solution in the medium term, especially for aircraft engines of medium power classes, it makes sense to use an innovative, electrically parallel hybrid unit based on rotary engines and electric boosters for start and climb phases as a propulsion system. An aero-engine application, based on the HSD concept (HSD = hybrid super-drive - hybrid Wankel rotary engine) for different hybrid-parallel propulsion systems is presented. In this article, the introduced technology is based on a currently produced family of multi-component Wankel rotary engines. The proposed HSD concept uses a chamber volume of 650ccm per rotor. The projected power range (0.8 to 1.36 MW) is covered by an innovative hybrid electric parallel turbo compound concept together with 2x4 rotary engine units. A novel, airbearing turbo engine with integrated electric drive is used as a turbocharger for charging the rotary engine. For the aero-engine technology, the counter-rotating fan (CRF) concept shown as an example for an aircraft technolo¬gy carrier (light jet) leads to a further increase in the efficiency of a complete system.}, language = {en} } @misc{PoojitganontAntoshkivWatjatrakuletal., author = {Poojitganont, Thanapol and Antoshkiv, Oleksiy and Watjatrakul, Boonchai and Berg, Heinz Peter}, title = {Efficiency and Emission Simulations of Hydrogen-Fuel City Buses}, series = {IOP Conference Series: Materials Science and Engineering}, journal = {IOP Conference Series: Materials Science and Engineering}, editor = {Ashton, Anete}, edition = {1. Auflage}, publisher = {IOP Science}, address = {Bristol}, issn = {1757-899X}, doi = {10.1088/1757-899X/886/1/012025}, pages = {1 -- 8}, abstract = {In this study, the AVL Cruise is implemented to simulate driving parameters including the driving path, the power loss on engine accessories, the gear-shifting scheme and the engine's fuel cut-off strategy influencing the bus fuel efficiency and emission. The Mercedes Conecto LF city bus using a diesel engine with Standardised On-Road Test Cycles was firstly simulated and compared with available literature. The application of hydrogen fuel was then examined and its result was compared with the diesel fuel on the specific fuel consumption. In addition, the driving cycles in Bangkok were simulated. The results show the pattern on both driving cycles with different fuel are similar, however, the fuel consumption of H2 is significantly less than in the case of Diesel. Moreover, it is also evident that the SORT driving cycle cannot represent the heavy traffic of Bangkok.}, language = {en} } @incollection{BondarenkoBergAntoshkiv, author = {Bondarenko, Evgeniiy and Berg, Heinz Peter and Antoshkiv, Oleksiy}, title = {Untersuchung des Verbrauchs- und Rekuperationspotentials eines Elektrobusses mit Turbo-Range-Extender mittels AVL Cruise}, series = {W{\"a}rmemanagement des Kraftfahrzeugs IX}, booktitle = {W{\"a}rmemanagement des Kraftfahrzeugs IX}, editor = {Steinberg, Peter}, publisher = {expert Verlag}, address = {Potsdam}, isbn = {978-3-8169-3275-8}, pages = {341 -- 356}, language = {de} } @article{AhlinderBiesoldBerg, author = {Ahlinder, Stefan and Biesold, Volker and Berg, Heinz Peter}, title = {Hot side flow investigation on the exhaust case of a recuperated industrial gas turbine}, language = {en} } @inproceedings{PoojitganontIzweikBerg, author = {Poojitganont, Thanapol and Izweik, Husni Taher and Berg, Heinz Peter}, title = {"Simulation of Flow Field inside the Wankel Combustion Chamber"}, language = {en} } @misc{XieStarickMosgowetal., author = {Xie, Tianxiao and Starick, Tommy and Mosgow, Anatol and Berg, Heinz Peter and H{\"o}schler, Klaus and Schmidt, Heiko}, title = {Thermofluiddynamic pre-design of a primary surface heat exchanger under the influence of heat radiation using 1D/3D coupled simulation method}, series = {NAFEMS World Congress 2021, online, 25-29. Oktober 2021}, journal = {NAFEMS World Congress 2021, online, 25-29. Oktober 2021}, pages = {25}, abstract = {Within the Framework of the "TurboFuelCell (TFC)" a highly integrated and compact energy conversion system based on Micro Gas Turbine Solid Oxide Fuel Cell (MGT-SOFC) hybrid process is being developed by the team at BTU-Cottbus Senftenberg. This work focuses on the extension of the pre-design process of a primary surface heat exchanger (PSHX), which is a key component for the coupling between MGT and SOFC, using an 1D/3D hybrid simulation method for the understanding of its behaviour under the influence of heat radiation. In a MGT-SOFC hybrid process the high temperature heat exchanger plays an important role in preheating the fresh air to a minimum operation temperature necessary for SOFC. Due to the special location of this PSHX in the TFC, it is constantly exposed to heat radiation from the SOFC module, which requires additional consideration of its influence for better model accuracy. A first design, which is later extended through an 1D Flow network model, based on 𝜖 - 𝑁𝑇𝑈 method is presented. A complete 3D-CFD simulation with consideration of heat radiation is initially employed for the whole flow process to examine the first design. However, this approach proves to be highly computationally expensive due to the large dimensional difference between the plenum for cathode exhaust air and the fine channels in the PSHX. To reduce the computational effort, the flow and heat transfer in the PSHX is modelled by 1D elements. The flow in the plenum is simulated by 3D-CFD, which better accounts for convection and thermal radiation. A comparison between 3D-CFD and 1D/3D hybrid model is performed. A significant reduction of simulation time and computing resources can be achieved for well calibrated hybrid model without compromising on accuracy. In the talk, the effect of insulation layer thickness variations on the heat transfer on the plenum side due to heat radiation and their influence on the heat exchanger efficiency are discussed. Consequently, design improvements are realized based on the previous findings. Finally, the 1D/3D hybrid simulation method is evaluated and prepared for the general applications in thermal management of machines based on coupled MGT-SOFC process.}, language = {en} } @misc{XieMathiazhaganBarkowskietal., author = {Xie, Tianxiao and Mathiazhagan, Akilan and Barkowski, Daniel and Starick, Tommy and Berg, Heinz Peter and H{\"o}schler, Klaus}, title = {Comparison of convective heat transfer in metal foam-filled channels of three different cross-sections}, series = {Numerical Heat Transfer, Part A: Applications}, volume = {85}, journal = {Numerical Heat Transfer, Part A: Applications}, number = {2}, issn = {1521-0634}, doi = {10.1080/10407782.2023.2181892}, pages = {222 -- 236}, abstract = {This work introduces a new approach of analyzing convective heat transfer in porous medium by considering the foam structure as a type of fin. It provides the resulting heat transfer characteristics for the design of a longitudinally flowed tube bundle reformer used for the Micro Gas Turbine Solid Oxide Fuel Cell (MGT-SOFC) hybrid process. Owing to a limited experimental database available in literature for the above-mentioned situation, a physical model is initially introduced for a channel flow configuration between two large flat plates using a commercial PDE solver. This model is then validated with experimental results available in literature. A comparison with theoretical solutions is also conducted. Later, this model is modified/adapted for a pipe flow configuration. The physical model for a channel with representative cross-section shape of a longitudinally flowed tube bundle is more complex and is therefore built in a commercial CFD-Solver. A comparative study of the heat transfer behavior in channels of different cross-sections is performed based on a new dimensionless correlation, whose physical coherence with fin efficiency is explained and mathematically proved. The applicability of the heat transfer correlation from one cross-sectional shape to the other are discussed. The proposed new treatment of the porous medium as a fin structure considerably simplifies the heat transfer analysis in porous medium by the clear physical meaning behind fin efficiency and Biot number. This relationship contributes to a better understanding of the heat heat transfer characteristics in porous media in contrast to the correlation between Nusselt number and Reynolds number. Furthermore, this correlation enables a direct comparison between foam structures of different parameters because the fin efficiency is always between 0 and 1. The strong physical background of new correlations also enhances the reliability and plausibility at characterizing and designing the metal foam for heat transfer enhancement.}, language = {en} }