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Joachim Kurzke - One of the best experts on this subject based on the ideXlab platform.
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Gas Turbine Cycle Design Methodology: A Comparison of Parameter Variation With Numerical Optimization
Journal of Engineering for Gas Turbines and Power, 1999Co-Authors: Joachim KurzkeAbstract:In gas turbine performance simulations often the following question arises : what is the best thermodynamic Cycle Design point? This is an optimization task which can be attacked in two ways. One can do a series of parameter variations and pick from the resulting graphs the best solution or one can employ numerical optimization algorithms that produce a single Cycle that fulfills all constraints. The conventional parameter study builds strongly on the engineering judgement and gives useful information over a range of parameter selections. However, when values for more than a few variables have to be determined while several constraints are existing, then numerical optimization routines can help to find the mathematical optimum faster and more accurately. Sometimes even an outstanding solution is found which was overlooked while doing a preliminary parameter study. For any simulation task a sophisticated graphical user interface is of great benefit. This is especially true for automated numerical optimizations. It is quite helpful to see on the screen of a PC how the variables are changing and which constraints are limiting the Design. A quick and clear graphical representation of trade studies is also of great advantage. The paper describes how numerical optimization and parameter studies are implemented in a Windows-based PC program. As an example, the Cycle selection of a derivative turbofan engine with a given core shows the merits of numerical optimization. The parameter variation is best suited for presenting the sensitivity of the result in the neighborhood of the optimum Cycle Design point.
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Gas Turbine Cycle Design Methodology: A Comparison of Parameter Variation With Numerical Optimization
Volume 2: Aircraft Engine; Marine; Microturbines and Small Turbomachinery, 1998Co-Authors: Joachim KurzkeAbstract:In gas turbine performance simulations often the question arises: What is the best thermodynamic Cycle Design point? This is an optimization task which can be attacked in two ways: One can do a series of parameter variations and pick from the resulting graphs the best solution or one can employ numerical optimization algorithms that produce a single Cycle which fulfills all constraints.The conventional parameter study builds strongly on the engineering judgement and gives useful information over a range of parameter selections. However, when values for more than a few variables have to be determined while several constraints are existing, then numerical optimization routines can help to find the mathematical optimum faster and more accurately. Sometimes even an outstanding solution is found which was overlooked while doing a preliminary parameter study.For any simulation task a sophisticated graphical user interface is of great benefit. This is especially true for automated numerical optimizations. It is quite helpful to see on the screen of a PC how the variables are changing and which constraints are limiting the Design. A quick and clear graphical representation of trade studies is also of great advantage. The paper describes how numerical optimization and parameter studies are implemented in a Windows-based PC program.As an example, the Cycle selection of a derivative turbofan engine with a given core shows the merits of numerical optimization. The parameter variation is best suited for presenting the sensitivity of the result in the neighborhood of the optimum Cycle Design point.Copyright © 1998 by ASME
Gregory A Keoleian - One of the best experts on this subject based on the ideXlab platform.
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LIFE Cycle Design OF A FUEL TANK SYSTEM.
1998Co-Authors: Gregory A Keoleian, Sabrina Spatari, Robb T. BealAbstract:This life Cycle Design (LCD) project was a collaborative effort between the National Pollution Prevention Center at the University of Michigan, General Motors (GM), and the U.S. Environmental Protection Agency (EPA). The primary objective of this project was to apply life Cycle Design tools to guide the improvement of fuel tank systems. Two alternative fuel tank systems used in a 1996 GM vehicle line were investigated: a multi-layer high density polyethylene (HDPE) tank system, and a steel tank system. The Design analysis included a life Cycle inventory (LCI) analysis, performance analysis and preliminary life Cycle cost analysis. The scope of the LCI study encompassed materials production, the manufacturing processes for each tank system, the contribution of each tank system to the use phase burdens of the vehicle, and the end-of-life management processes based on the current vehicle retirement infrastructure. The LCI analysis indicated lower energy burdens for the HDPE tank system and comparable solid waste burdens for both systems. Based on the results of the LCI, streamlined environmental metrics were proposed. While both systems meet basic performance requirements, the HDPE system offers Design flexibility in meeting capacity requirements, and also provided a fuel cost savings. The life Cycle Design framework was useful in evaluating environmental, performance, and cost trade-offs among and between both fuel tank systems. Life Cycle Design of a Fuel Tank System
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Amorphous silicon photovoltaic modules: a life Cycle Design case study
Proceedings of the 1996 IEEE International Symposium on Electronics and the Environment. ISEE-1996, 1996Co-Authors: G Lewis, Gregory A KeoleianAbstract:The life Cycle Design framework was applied to photovoltaic module Design. Two metrics were used to assess life Cycle energy performance of a PV module: energy payback time; and electricity production efficiency. These metrics are based on material production, manufacturing, and transportation energies, and were evaluated for several geographic locations. An aluminum frame was responsible for a significant fraction of the total energy invested in the studied module. Design options to reduce the energy impact of this and other components are discussed.
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Life Cycle Design framework and demonstration projects
1995Co-Authors: Gregory A Keoleian, CurranAbstract:Life Cycle Design is a proactive approach for integrating pollution prevention and resource conservation strategies into the development of more ecologically safe and economically sustainable products. The following key elements are described: a firm`s environmental management system; needs analysis; Design specification requirements; selection of Design strategies for minimizing environmental burden; and evaluation of Design alternatives using environmental analysis tools.
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Life Cycle Design Criteria for Engine Oil Filters: AlliedSignal Case Study
SAE Technical Paper Series, 1995Co-Authors: Gregory A KeoleianAbstract:The life Cycle Design framework developed at the University of Michigan was applied by AUiedSignal to improve the manufacture, use, and end-of-lie management of automobile oil filters. Three oil filter Designs were investigated: a conventional spin-on fdter which is a singleuse producr a cartridge filter consisting of a reusable housing and a replacement Camidge, and a cleanable Design which uses a reusable housing and cleanable fdter element Environmental, cost, performance, and legal requirements were developed using a matrix tool and tradmffs between these requirements were studied. These Design criteria are presented along with results from an analysis of user life Cycle costs and a simplified life Cycle energy analysis. Key elements of the life Cycle Design framework, which is based on systems analysis, multiobjective analysis, and multistakeholder panicipation, are also described
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Life Cycle Design: AT&T demonstration project
Proceedings of 1994 IEEE International Symposium on Electronics and The Environment, 1Co-Authors: Gregory A Keoleian, W.j. Glantschnig, W. MccannAbstract:Summary form only given. The life Cycle Design framework developed at the University of Michigan guides the integration of environmental requirements into the manufacturing, use, and end-of-life states of a product system. Elements of the life Cycle Design framework were applied in AT&T's product realization process for a business phone. This demonstration project tested the use of a multicriteria requirements matrix which includes environmental, performance, cost, cultural, and legal dimensions. Critical requirements that shape the Design of the business phone were identified and life Cycle Design strategies used to resolve conflicts between these requirements are highlighted in this paper. In addition, challenges in implementing life Cycle Design such as insufficient environmental data and lack of consensus on environmental assessment are discussed. >
Yasushi Umeda - One of the best experts on this subject based on the ideXlab platform.
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LC-CAD: A CAD system for life Cycle Design
CIRP Annals, 2012Co-Authors: Yasushi Umeda, Shinichi Fukushige, Eisuke Kunii, Yuki MatsuyamaAbstract:Abstract In product life Cycle Design, a Designer should Design both a product and its life Cycle. Although CAD systems for product Design are popular, there are no CAD systems for life Cycle Design. This paper proposes LC-CAD (Life Cycle-CAD) that represents a product and its life Cycle in an integrated manner, manages consistency between these two models, and describes changes of a product along its life Cycle ( e.g. , a component is shredded into fragments of metal in a recycling process). LC-CAD also evaluates environmental, economic, and other performance of Designed life Cycle using life Cycle simulation.
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product modularity for life Cycle Design
Cirp Annals-manufacturing Technology, 2008Co-Authors: Yasushi Umeda, Shinichi Fukushige, Keita Tonoike, Shinsuke KondohAbstract:Modular Design is an important elemental technique in life Cycle Design for improving, e.g., maintainability, upgradability, reusability, and recyclability. Appropriate modular structure differs according to applied life Cycle options; e.g., while the modular structure for recycling should be based on material kinds, the structure for upgrading should be based on functions to be obsolete. This paper proposes a method for determining modular structure by aggregating various attributes related to a product life Cycle and evaluating geometric feasibility of modules. This paper also illustrates the prototype system that implements the proposed method and a case study of a printer.
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Experiences of Teaching “Life Cycle Design” Course at Tokyo Metropolitan University
Manufacturing, 2003Co-Authors: Yasushi UmedaAbstract:This paper describes the outline of “life Cycle Design” course the author teaches and illustrates some experiences and findings with results of questionnaires to attendees of the lecture. “Life Cycle Design” is a half-year course to third-year students at Tokyo Metropolitan University, Japan. The main subject is environmentally conscious Design focusing on life Cycle thinking. This course intends to establish general and correct viewpoints toward relationship between manufacturing industry and the environmental issues, which are indispensable knowledge as mechanical engineers, rather than to educate environmental specialists. Results of questionnaires indicate that this course succeeded in increasing students’ interest in this area and awareness of importance of the environmental issues. However, some students feel bewildered because of wide variety of topics and, therefore, lack of a central theory.Copyright © 2003 by ASME
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toward a life Cycle Design guideline for inverse manufacturing
International Symposium on Environmentally Conscious Design and Inverse Manufacturing, 2001Co-Authors: Yasushi UmedaAbstract:For achieving the sustainability, it is essential to establish sustainable product life Cycles that minimize resource consumption and discharge of emissions and wastes, while keeping and increasing wealth. This paper discusses fundamental issues of life Cycle Design, which is defined as integrated Design of business strategy, life Cycle strategy; product, and processes. For guiding determination of life Cycle strategy; this paper clarifies applicability of life Cycle options; especially, issues of component reuse are discussed including lifetime, costs, value and quality; and marginal reuse rate. As a result, life Cycle Design is indispensable for making reuse feasible. Finally; this paper points out some future issues for sustainable closed-loop product life Cycles.
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study on life Cycle Design for the post mass production paradigm
Ai Edam Artificial Intelligence for Engineering Design Analysis and Manufacturing, 2000Co-Authors: Yasushi Umeda, Akira Nonomura, Tetsuo TomiyamaAbstract:Environmental issues require a new manufacturing paradigm because the current mass production and mass consumption paradigm inevitably cause them. We have already proposed a new manufacturing paradigm called the “Post Mass Production Paradigm (PMPP)” that advocates sustainable production by decoupling economic growth from material and energy consumption. To realize PMPP, appropriate planning of a product life Cycle (Design of life Cycle) is indispensable in addition to the traditional environmental conscious Design methodologies. For supporting the Design of a life Cycle, this paper proposes a life-Cycle simulation system that consists of a life-Cycle simulator, an optimizer, a model editor, and knowledge bases. The simulation system evaluates product life Cycles from an integrated view of environmental consciousness and economic profitability and optimizes the life Cycles. A case study with the simulation system illustrates that the environmental impacts can be reduced drastically without decreasing corporate profits by appropriately combining maintenance, reuse and recycling, and by taking into consideration that optimized modular structures differ according to life-Cycle options.
Jie Zhou - One of the best experts on this subject based on the ideXlab platform.
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PHGWO: A Duty Cycle Design Method for High-density Wireless Sensor Networks
2019 IEEE International Conference of Intelligent Applied Systems on Engineering (ICIASE), 2019Co-Authors: Jie ZhouAbstract:High-density wireless sensor networks (HDWSNs) have many abilities such as computing, wireless communication, information acquisition, and free-infrastructure capabilities. In HDWSNs, the duty Cycle Design method is crucial because the energy of a battery is limited. To have a longer network lifetime, duty Cycle scheme should be Designed properly. Hence, a new parallel hybrid grey wolf optimization (PHGWO) is proposed in this paper for solving the duty Cycle Design problem. In the experiments, we compare the network lifetime of PHGWO with genetic algorithm (GA), shuffled frog leaping algorithm (SFLA) and particle swarm optimization (PSO). Simulation results show that the PHGWO for the duty Cycle Design problem in HDWSN enjoys an optimizing the system efficiency compared to the conventional GA, SFLA and PSO methods while maintaining lifetime optimization. PHGWO has displayed strong capabilities to obtain a better convergence as well as prevents local optima by means of visiting the space.
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A Biologically Inspired Energy-Efficient Duty Cycle Design Method for Wireless Sensor Networks
Journal of Sensors, 2017Co-Authors: Jie ZhouAbstract:The recent success of emerging wireless sensor networks technology has encouraged researchers to develop new energy-efficient duty Cycle Design algorithm in this field. The energy-efficient duty Cycle Design problem is a typical NP-hard combinatorial optimization problem. In this paper, we investigate an improved elite immune evolutionary algorithm (IEIEA) strategy to optimize energy-efficient duty Cycle Design scheme and monitored area jointly to enhance the network lifetimes. Simulation results show that the network lifetime of the proposed IEIEA method increased compared to the other two methods, which means that the proposed method improves the full coverage constraints.
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BODYNETS - Energy efficient duty Cycle Design based on quantum immune clonal evolutionary algorithm in body area networks
Proceedings of the 10th EAI International Conference on Body Area Networks, 2015Co-Authors: Jie Zhou, Eryk Dutkiewicz, Ren Ping Liu, Gengfa Fang, Yuanan LiuAbstract:Duty Cycle Design is an important topic in body area networks. As small sensors are equipped with the limited power source, the extension of network lifetime is generally achieved by reducing the network energy consumption, for instance through duty Cycle schemes. However, the duty Cycle Design is a highly complex NP-hard problem and its computational complexity is too high with exhaustive search algorithm for practical implementation. In order to extend the network lifetime, we proposed a novel quantum immune clonal evolutionary algorithm (QICEA) for duty Cycle Design while maintaining full coverage in the monitoring area. The QICEA is tested, and a performance comparison is made with simulated annealing (SA) and genetic algorithm (GA). Simulation results show that compared to the SA and the GA, the proposed QICEA can extending the lifetime of body area networks and enhancing the energy efficiency effectively.
Dimitri N. Mavris - One of the best experts on this subject based on the ideXlab platform.
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Multi-Design Point Cycle Design Incorporation into the Environmental Design Space
48th AIAA ASME SAE ASEE Joint Propulsion Conference & Exhibit, 2012Co-Authors: Jeff Schutte, Jimmy C. Tai, Dimitri N. MavrisAbstract:A multi-point Design Cycle analysis methodology has been developed and implemented into the Environmental Design Space to ensure the proper matching of engine and aircraft. The method ensures the feasibility of the engine Designs throughout the Cycle Design space by adjusting the Design to simultaneously meet performance requirements and constraints at different operating conditions. EDS incorporates NPSS for the Cycle analysis and utilizes its solver to find the solution of a system of nonlinear equations established by the user and the NPSS auto solver to that meets all requirements and constraints.
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Cycle Design Exploration Using Multi-Design Point Approach
Volume 1: Aircraft Engine; Ceramics; Coal Biomass and Alternative Fuels; Controls Diagnostics and Instrumentation, 2012Co-Authors: Jeffrey S. Schutte, Jimmy C. Tai, Jonathan S. Sands, Dimitri N. MavrisAbstract:The focus of this study is to compare the aerothermodynamic Cycle Design space of a gas turbine engine generated using two on-Design approaches. The traditional approach uses a single Design point (SDP) for on-Design Cycle analysis, where off-Design Cycle analysis must be performed at other operating conditions of interest. A multi-Design point (MDP) method performs on-Design Cycle analysis at all operating conditions where performance requirements are specified. Effects on the topography of the Cycle Design space as well as the feasibility of the space are examined. The impacts that performance requirements and Cycle assumptions have on the bounds and topography of the feasible space are investigated. The deficiencies of a SDP method in determining an optimum gas turbine engine will be shown for a given set of requirements. Analysis will demonstrate that the MDP method, unlike the SDP method, always obtains a properly sized engine for a set of given requirements and Cycle Design variables, resulting in an increased feasible region of the aerothermodynamic Cycle Design space from which the optimum performance engine can be obtained.Copyright © 2012 by ASME
