TY - CHAP A1 - Hendler, Marco A1 - Extra, Simon A1 - Lockan, Michael A1 - Bestle, Dieter A1 - Flassig, Peter Michael T1 - Compressor Design in the Context of Holistic Aero Engine Design T2 - 2017 AIAA Aviation Forum, Denver, AIAA-2017-3334, 2017 KW - Holistic Optimization KW - Aero Engines KW - Computational Fluid Dynamics Y1 - 2017 U6 - https://doi.org/10.2514/6.2017-3334 ER - TY - CHAP A1 - Extra, Simon A1 - Lockan, Michael A1 - Bestle, Dieter A1 - Flassig, Peter Michael T1 - A Comparison of Strategies for Efficient Core Engine Optimization with Coupled Subsystems T2 - Proceedings of Montreal 2018, Global Power and Propulsion Forum, 7-9.05.2018 N2 - The present paper compares four different optimization strategies for decoupled optimization in the context of preliminary core engine design for aero engines. An optimization with the AAO (All-At-Once) approach is performed as a baseline and compared against the performance and results of three cascaded optimization strategies: CO (Collaborative Optimization), BLISS 2000 (Bi-Level Integrated System Synthesis) and ISOC (Interface Segmentation Optimization Concept). The optimization problem is based on a thermodynamic core engine model representing an industrial application example. The results are assessed with respect to typical requirements for multidisciplinary core engine design. The impact of the used optimization strategy on the performance of the optimization concept is investigated and discussed. Y1 - 2018 UR - https://gpps.global/documents/events/montreal18/papers/design-modeling/GPPS-NA-2018-0097.pdf N1 - GPPS-NA-2018-0097 ER - TY - CHAP A1 - Extra, Simon A1 - Lockan, Michael A1 - Bestle, Dieter A1 - Flassig, Peter Michael T1 - Coupled Subsystem Optimization for Preliminary Core Engine Design T2 - Evolutionary and deterministic methods for design optimization and control with applications to industrial and societal problems, Sep. 13-15, 2017 in Madrid, Spain, EUROGEN 2017, Book of abstracts Y1 - 2017 SN - 978-84-697-5112-1 PB - Technical University CY - Madrid ER - TY - CHAP A1 - Extra, Simon A1 - Lockan, Michael A1 - Bestle, Dieter A1 - Flassig, Peter Michael ED - Andrès-Pèrez, Esther ED - González, Leo M. ED - Periaux, Jacques ED - Gauger, Nicolas R. ED - Quagliarella, Domenico ED - Giannakoglou, Kyriakos C. T1 - Coupled Subsystem Optimiziation for Preliminary Core Engine Design T2 - Evolutionary and Deterministic Methods for Design Optimization and Control With Applications to Industrial and Societal Problems Y1 - 2018 SN - 978-3-319-89889-6 SN - 978-3-319-89890-2 U6 - https://doi.org/10.1007/978-3-319-89890-2_33 SP - 513 EP - 527 PB - Springer International Publishing CY - Cham ER - TY - CHAP A1 - Lockan, Michael A1 - Bestle, Dieter T1 - Robustheitsaspekte in verteilten Entwicklungsumgebungen T2 - 4. Dresdener Probabilistik Workshop, 06.10. - 07.10.2011, Dresden Y1 - 2011 UR - http://www.probabilistik.de/vortrag/v2011_lockan.pdf ER - TY - CHAP A1 - Lockan, Michael A1 - Bestle, Dieter T1 - A Concept for Collaborative Design and Distributed Optimisation T2 - 5th IC-SCCE International Conference: From Scientific Computing to Computational Engineering, Athen, 2012 N2 - The paper shows a methodology for designing a complex system in a collaborative design environment by sharing information on autonomous subsystems and coupling parameters. Collaborative design is a current issue in aviation industry where intellectual property rights of individual companies prohibit a common evaluation model. State of the art approaches based on nested local optimisation loops are not sufficient if time-consuming component analyses are involved. A new approach for collaborative design is developed where the overall optimisation of a complex system is split into subsystem optimisation problems. Coupling parameters are treated as local design variables and only optimal coupling parameters are exchanged regularly. Application to a test example shows a huge time reduction and improved probability for finding the global optimum. Advantages are also demonstrated for an industrial design task. KW - collaborative design, distributed computation, optimisation Y1 - 2012 UR - http://www.epsmso.gr/all_conf_index/index.html SN - 978-960-98941-9-7 ER - TY - CHAP A1 - Amtsfeld, Philipp A1 - Lockan, Michael A1 - Bestle, Dieter A1 - Meyer, Markus T1 - Accelerated 3D Aerodynamic Optimization of Gas Turbine Blades T2 - ASME Turbo Expo 2014, Turbine Technical Conference and Exposition, Volume 2B: Turbomachinery, Düsseldorf, Germany, June 16–20, 2014 KW - Turbine Blade Optimization Y1 - 2014 SN - 978-0-7918-4561-5 N1 - GT2014-25618 PB - ASME CY - New York, NY ER - TY - CHAP A1 - Lockan, Michael A1 - Amtsfeld, Philipp A1 - Bestle, Dieter A1 - Meyer, Marcus T1 - Non-Linear Sensitivity Analysis Based on Regression Trees with Apllication to 3D Aerodynamic Optimization of Gas Turbine Blades T2 - International Conference on Engineering and Applied Scieces Optimization (OPT-i), Kos, Griechenland, 2014 KW - Sensitivity Analysis, Dimension Reduction, Regression Trees, Response Surface Optimization Y1 - 2014 SN - 978-960-99994-5-8 ER - TY - CHAP A1 - Lockan, Michael A1 - Bestle, Dieter A1 - Janke, Christian A1 - Meyer, Marcus T1 - Optimization of Coupled System Components Using Approximations of Interface Quantities T2 - ASME Turbo Expo 2017, Turbomachinery Conference and Exposition, Volume 2C, Turbomachinery Charlotte, North Carolina, USA, June 26-30, 2017 KW - Optimization KW - Approximation Y1 - 2017 SN - 978-0-7918-5080-0 U6 - https://doi.org/10.1115/GT2017-64135 N1 - GT2017-64135 PB - ASME CY - New York, NY ER - TY - THES A1 - Lockan, Michael T1 - Kooperative Optimierung komplexer Systeme durch Segmentierung des Interface-Raums N2 - Die Auslegung von komplexen technischen Systemen ist ein Prozess, bei welchem Experten verschiedener Disziplinen, Abteilungen oder sogar Firmen sehr eng zusammenarbeiten müssen. Aufgrund der Komplexität oder auch aus politischen Gründen existiert im Allgemeinen eine einzelne System-Analyse nicht und unterschiedliche Subsystem-Analysen müssen in geeigneter Weise gekoppelt werden, um das Verhalten des Gesamtsystems zu bestimmen. Dabei stellt besonders in kooperativen Entwicklungsumgebungen, wenn möglicherweise konkurrierende Firmen zusammenarbeiten müssen, diese Kopplung eine große Herausforderung dar. Die Optimierung von komplexen Systemen findet heutzutage hauptsächlich im Rahmen von automatisierten Subsystem-Optimierungen statt. Die Schnittstellen zwischen den einzelnen Subsystemen werden dabei in frühen Entwurfsphasen auf Grundlage von Erfahrungswerten oder einfacher Abschätzungen festgelegt und nachfolgend nicht mehr wesentlich verändert. Diese Schnittstellen bestimmen jedoch maßgeblich die erreichbare Leistungsfähigkeit des Systems, und sollten daher während des gesamten Optimierungsprozesses unter Verwendung detaillierter Subsystem-Analysen hinterfragt und gezielt angepasst werden. Die dafür benötigten multidisziplinären Optimierungsverfahren müssen dabei alle beteiligten Analysemodelle in effizienter Weise koordinieren, damit eine Anwendung in praktischen Problemstellungen und hohen Entwurfsraumdimensionen erfolgen kann. Der Fokus dieser Arbeit liegt daher auf der Entwicklung eines effizienten Verfahrens zur Optimierung komplexer Systeme unter besonderer Beachtung eines kooperativen Hintergrundes. Es wird gezeigt, wie Antwortflächen-Verfahren verwendet werden können, um die Subsystem-Optimierungen zu beschleunigen und somit auch zeitaufwändige Analysen im Rahmen einer System-Optimierung einzusetzen. Durch die Analyse bestehender Verfahren wird die generelle Struktur kooperativer Optimierungen verdeutlicht und eine Einordnung des entwickelten ISOC-Verfahrens ermöglicht. Dessen ausführliche Herleitung und Darstellung zeigt die einfache Anpassung der vorhandenen Subsystem-Prozesse und demonstriert die Einbindung in die System-Optimierung. Die Anwendungen auf repräsentative Probleme aus der Triebwerkstechnik zeigen zum Einen die Vorteile paralleler und entkoppelter Optimierungen, und zum Anderen, dass das entwickelte ISOC-Verfahren in der Lage ist, praktische Problemstellungen zu lösen. Y1 - 2017 SN - 978-3-8440-5455-2 PB - Shaker Verlag GmbH CY - Aachen ER - TY - RPRT A1 - Bestle, Dieter A1 - Lockan, Michael A1 - Hartwig, Lennard A1 - Martin, Ivo T1 - Q3D Optimierung vielstufiger Verdichter in der Vorauslegung und robuste multidisziplinäre Schaufelauslegung Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:co1-opus4-42225 SN - 978-3-940471-30-7 PB - Brandenburgische Technische Universität Cottbus-Senftenberg, IKMZ-Universitätsbibliothek CY - Cottbus ; Senftenberg ER - TY - GEN A1 - Kriese, Maximilian A1 - Lockan, Michael A1 - Schaffrath, Robert A1 - Stathopoulos, Panagiotis T1 - Quasi-static simulation of a start-up procedure for a multistage centrifugal compression system T2 - Proceedings of ASME Turbo Expo 2025 : Turbomachinery Technical Conference and Exposition, June 16-20, 2025, Memphis, Tennessee : Volume 4 : Controls, Diagnostics & Instrumentation; Cycle Innovations; Education; Electric Power N2 - In order to achieve the European Union’s climate protection targets by 2050, energy use in the private and industrial sectors must be switched from using fossil fuels to renewable energy. For industry, this might require that the production processes itself needed to be changed or new technologies to manufacture in a sustainable way needed to be introduced. One example of the latter mentioned are high-temperature heat pumps (HTHP), which will be capable to generate sustainable process heat up to 300°C e.g. for the pulp and paper or food industry. There are currently only a few HTHPs commercially available that can reach temperatures above 150°C. In order to overcome the technological challenges to reach 300°C, two HTHP prototypes are currently developed at the Institute of Low-Carbon Industrial Processes of the German Aerospace Centre (DLR). One of them is the pilot plant ZiRa which is based on the reversed Rankine process and uses steam as its working medium. Herein three centrifugal compressors are applied to achieve a saturated steam temperature of 200°C at the sink. The safe speed-up of these three compressors, titled as the start-up procedure, from the standstill of each compressors up to their respective nominal speed, is modelled in the flow chart software EBSILON Professional. In addition to the compressors, all necessary components, i.e. the intercoolers, the fittings and valves, the pipes, the separators and the bypasses are modelled so that all parameters influencing the thermodynamic inlet state of the respective compressor are considered. The start-up of the multi-stage compression system of the pilot plan ZiRa is shown as a quasi-static time series. As a first step, the speed increments are defined. Afterwards, absolute pressures between 1.25 and 2 bar upstream of the first compressor and their effect on the operation of the subsequent compressor stages, are analyzed. Therefore, the mass flow rates and rotational speeds are specified manually at first so that an executable, editable model is created. Based on these results, the operation of the compressors are optimized in order to ensure a surge margin of 15 % and to avoid choke in each operating point. KW - High temperature heat pump KW - Compressor startup KW - Reverse Rankine cycle KW - Process simulation Y1 - 2025 SN - 978-0-7918-8880-3 U6 - https://doi.org/10.1115/GT2025-151935 PB - American Society of Mechanical Engineers CY - New York, NY ER -