Showing papers on "Design tool published in 2006"

CoilDesigner: a general-purpose simulation and design tool for air-to-refrigerant heat exchangers

Abstract: A simulation and design tool to improve effectiveness and efficiency in design, and analysis of air to refrigerant heat exchangers, CoilDesigner, is introduced. A network viewpoint was adopted to establish the general-purpose solver and allow for analysis of arbitrary tube circuitry and mal-distribution of fluid flow inside the tube circuits. A segment-by-segment approach within each tube was implemented, to account for two-dimensional non-uniformity of air distribution across the heat exchanger, and heterogeneous refrigerant flow patterns through a tube. Coupled heat exchangers with multiple fluids inside different subsets of tubes can be modeled and analyzed simultaneously. A further sub-dividing-segment model was developed in order to address the significant change of properties and heat transfer coefficients in the single-phase and two-phase regime when a segment experiences flow regime change. Object-oriented programming techniques were applied in developing the program to facilitate a modular, highly flexible and customizable design platform and in building a graphic user-friendly interface. A wide variety of working fluids and correlations of heat transfer and pressure drop are available at the user's choice. The model prediction with CoilDesigner was verified against experimentally determined data collected from a number of sources.

An enhanced genetic algorithm for structural topology optimization

Abstract: Genetic algorithms (GAs) have become a popular optimization tool for many areas of research and topology optimization an effective design tool for obtaining efficient and lighter structures. In this paper, a versatile, robust and enhanced GA is proposed for structural topology optimization by using problem-specific knowledge. The original discrete black-and-white (0–1) problem is directly solved by using a bit-array representation method. To address the related pronounced connectivity issue effectively, the four-neighbourhood connectivity is used to suppress the occurrence of checkerboard patterns. A simpler version of the perimeter control approach is developed to obtain a well-posed problem and the total number of hinges of each individual is explicitly penalized to achieve a hinge-free design. To handle the problem of representation degeneracy effectively, a recessive gene technique is applied to viable topologies while unusable topologies are penalized in a hierarchical manner. An efficient FEM-based function evaluation method is developed to reduce the computational cost. A dynamic penalty method is presented for the GA to convert the constrained optimization problem into an unconstrained problem without the possible degeneracy. With all these enhancements and appropriate choice of the GA operators, the present GA can achieve significant improvements in evolving into near-optimum solutions and viable topologies with checkerboard free, mesh independent and hinge-free characteristics. Numerical results show that the present GA can be more efficient and robust than the conventional GAs in solving the structural topology optimization problems of minimum compliance design, minimum weight design and optimal compliant mechanisms design. It is suggested that the present enhanced GA using problem-specific knowledge can be a powerful global search tool for structural topology optimization. Copyright © 2005 John Wiley & Sons, Ltd.

A Design Tool for Aerodynamic Lens Systems

Abstract: We report in this article the development of a tool to design and evaluate aerodynamic lens systems: the Aerodynamic Lens Calculator. This Calculator enables quick and convenient design of aerodynamic lens systems based on the parameterized knowledge gained from our detailed numerical simulations of flow and particle transport through aerodynamic lens systems. It designs the key dimensions of a lens system: pressure limiting orifice, relaxation chamber, focusing lenses, spacers and the accelerating nozzle. It also provides estimates of particle terminal axial velocities, particle beam width, and particle transmission efficiencies. This article describes in detail the information that is used in the design tool, including equations for pressure drop through orifices, contraction factors as a function of Reynolds, Mach and Stokes numbers, spacer length as a function of Reynolds number and estimations for the relaxation chamber dimensions. The article also evaluates the performance of the design tool by comp...

Hierarchical presentation techniques for a design tool

Abstract: A design tool hierarchically presents information about a design with nested blocks. For example, the design tool presents scheduling information for the design in a hierarchical Gantt chart. The scheduling information includes hierarchical design schedule blocks which accurately depict the timing and scheduling of the nested blocks of the design. Each of the hierarchical design schedule blocks includes control steps numbered relative to the block. The scheduling information also includes a hierarchical list of scheduled operations for the design. The hierarchical list emphasizes which operations are associated with which nested blocks. The scheduling information further includes pseudo-operation icons that are easily differentiated from real operation icons in the hierarchical Gantt chart.

A Validation Study of an Automated Concept Generator Design Tool

Abstract: The current version of the Concept Generator, an automated mathematically-based design tool, is studied in an effort to validate its general approach and establish research goals for further development. As part of the study, four undergraduate engineering researchers from the University of Missouri-Rolla and University of Texas at Austin execute a qualitative study of the software’s effectiveness at producing useful design solutions. The students engage in several activities designed to test the capabilities of this early version of the software. A report of their results and analyses identifies the benefits and disadvantages of the software (and underlying method) as viewed at this stage of development. Furthermore, the design solution data collected by the undergraduate researchers is analyzed more quantitatively during a post-study investigation. Both the qualitative and quantitative studies indicate that the Concept Generator is a promising first step toward the creation of an effective design tool for the conceptual phase of design. Furthermore, the student reports on their hands-on experiences with the software identify strengths and weaknesses of this early version of the Concept Generator and help establish many avenues for further development of the design tool.Copyright © 2006 by ASME

Auto-pipe and the X language: a pipeline design tool and description language

Abstract: Auto-Pipe is a tool that aids in the design, evaluation and implementation of applications that can be executed on computational pipelines (and other topologies) using a set of heterogeneous devices including multiple processors and FPGAs. It has been developed to meet the needs arising in the domains of communications, computation on large datasets, and real time streaming data applications. This paper introduces the Auto-Pipe design flow and the X design language, and presents sample applications. The applications include the Triple-DES encryption standard, a subset of the signal-processing pipeline for VERITAS, a high-energy gamma-ray astrophysics experiment. These applications are discussed and their description in X is presented. From X, simulations of alternative system designs and stage-to-device assignments are obtained and analyzed. The complete system permits production of executable code and bit maps that may be downloaded onto real devices. Future work required to complete the Auto-Pipe design tool is discussed.

An automated design tool for analog layouts

Abstract: In this paper, a layout synthesis tool for the design of analog integrated circuits (ICs) is presented. This tool offers great flexibility that allows analog circuit designers to bring their special design knowledge and experiences into the synthesis process to create high-quality analog circuit layouts. Different from conventional layout systems that are limited to the optimization of single devices, our layout generation tool attempts to optimize more complex modules. This tool includes a complete tool suite that covers the following three major analog physical designs stages. 1) Module Generation: designers can develop and maintain their own technology- and application-independent module generators for subcircuits using an in-house developed description language. 2) Placement: a two-stage placement technique, tailored for the analog placement design, is proposed. In particular, this placement algorithm features a novel genetic placement stage followed by a fast simulated reannealing scheme. 3) Routing: the minimum-Steiner-tree-based global routing is developed, and it is actually integrated into the placement procedure to improve reliability and routability of the placement solutions. Following the global routing, a compaction-based constructive detailed routing finally completes the interconnection of the entire layout. Several testing circuits have been applied to demonstrate the design efficiency and the effectiveness of this tool. Experimental results show that this new layout tool is capable of producing high quality layouts comparable to those manually done by layout experts but with much less design time

Scalable vector graphics, tree and tab as drag and drop objects

Abstract: A mechanism is disclosed for providing Scalable Vector Graphics (SVG) images, Tree and Tab as drag and drop objects. A page design tool receives an indication that a user wishes to place a metadata-defined image onto a page design canvas. The page design tool further receives an association of metadata defining the image, and in response, parses through the metadata to identify properties and characteristics of the metadata-defined image to expose to a user through a graphical user-interface of the page design tool. The page design tool enables a user to assign conditions to the exposed properties and characteristics of the image, as well as map available data sources to the properties and characteristics in order to dynamically control image properties during display. Hence, the page design tool presents graphical user interface tools for simply incorporating otherwise complex objects into page designs.

EM-based microwave circuit design using fuzzy logic techniques

Abstract: The authors illustrate how EM simulators can be combined with fuzzy logic techniques to develop an efficient approach for designing microwave circuits. They demonstrate the approach by considering the design of a microstrip coupler, a microstrip 6-pole filter and an HTS microstrip 3-pole filter. The fuzzy logic system (FLS) is constructed using data pairs generated from an EM simulator. The FLS is employed as a design tool to directly synthesise the coupler and the filter physical dimensions for a required RF response. The results achieved demonstrate the validity of the proposed approach.

Multi-Objective and Multidisciplinary Design Optimization of Supersonic Fighter Wing

Abstract: An aerodynamic/structural multidisciplinary design with multiple objectives was carried out for the supersonic fighter wing using response surface methodology. Through a series of static aeroelastic analyses of a variety of candidate wings, the aerodynamic performance and structural strength were calculated. Nine wing and airfoil parameters were chosen for the aerodynamic design variables, and four structural variables were added to determine the wing skin thickness. To consider various flight conditions, multipoint design optimization was performed on the three representative design points. As expected, the single-point design shows the most improved performance on its own design point, but it produces inferior results by not satisfying some constraints on other design points. To improve the performances evenly and moderately at all design points, a multipoint optimal design was conducted. A genetic algorithm was also introduced to control the weight of the multiple objectives. The multipoint designed wing features improved performance and satisfies whole constraints at all design points. It is similar to the real supersonic fighter wing that was developed through numerous wind-tunnel tests and tradeoff studies. The proposed multidisciplinary design optimization framework could be adopted as an efficient practical design tool for the supersonic fighter wing to fix the basic geometry at a conceptual design stage.

Application of computational fluid dynamics to the design of pico propeller turbines

Abstract: A research project is currently being undertaken in collaboration with Practical Action (ITDG) to develop a standard design procedure for pico propeller turbines that can be manufactured locally in developing countries. A 5 kW demonstration turbine has been set up at a test site in Peru and Computational Fluid Dynamics (CFD) has been used to obtain overall performance data for the turbine and to assist in the design of a new rotor. It was found that an incorrect matching between the turbine rotor design and the available flow rate at the site significantly affected the turbine operation and in order to provide an acceptable performance it was possible to adjust just the runner design and operating speed of the turbine. The paper will present the initial CFD and field test results, and discuss the process by which computational fluid modelling has been used as an appropriate design tool.

Method and system for automatically discovering and populating a palette of reusable dialog components

Abstract: The present invention permits a speech application design tool to dynamically acquire information for runtime components, such as Reusable Dialog Components (RDCs). More specifically, a user can identify a library available to the runtime environment that includes runtime speech components. Runtime components can be imported into an integrated development environment (IDE) that includes the software design tool. The tool can discover configuration grammars, audio, and data models associated with the imported components. When previously developed application code has been loaded into the tool, versions of components associated with the previously developed application will be compared and synchronized with the library components. Differences can be flagged by the tool, which facilitates a component upgrading process. Otherwise, a palette within the tool will be populated with the imparted components, which can be used when authoring a new application.

The Use of Genetic Algorithms for a net-Zero Energy Solar Home Design Optimisation Tool

Abstract: The application of computerised optimisation techniques to the design of low and net- zero energy buildings would provide building designers with a powerful design tool. This paper presents such a tool that is being developed that links TRNSYS energy simulation with an optimisation program based on genetic algorithms. This early design stage optimisation tool optimises 17 parameters including building width to length ratio, heating system type, solar thermal collector type and size, window sizes by orientation, and more, to find multiple design configurations that achieve a set energy consumption target.

Implementation of the Florida Cracking Model into the Mechanistic-Empirical Pavement Design

Abstract: Top-down cracking has been found to be a predominant mode of distresses of asphalt pavements in Florida. Therefore, it is important to accommodate top-down cracking in the design of asphalt mixtures and pavement structures. After a multi-year study on top-down cracking supported by the Florida Department of Transportation (FDOT), the University of Florida has developed a top-down cracking model based on the HMA fracture mechanics. This report presents the implementation of the Florida cracking model into a mechanistic-empirical (ME) flexible pavement design framework. Based on the energy ratio (ER) concept, a new ME pavement design tool for top-down cracking has been developed. In the Level 3 ME design, a series of material models were developed for estimation of the time-dependent material properties. With incorporation of the material properties models, the design tool is capable of performing pavement thickness design as well as pavement life prediction for top-down cracking in Florida. The thickness design is optimized for different traffic levels, mixture types, and binder selections. The AC thickness optimization is an automated process. This design tool has been packed into an interactive Windows-based software, making it convenient to use for pavement design engineers.

Automated modeling and analysis of CSMA-type access schemes for building automation networks

Abstract: During the design of large technical systems, the use of analytic and simulative models to test and dimension the system before implementation is of practical importance for an efficient and reliable design process. However, setting up the necessary models is time-consuming and therefore often too expensive in practice. Usually most information for modeling is already available in the design tool used to develop such extensive systems and only needs to be extracted for automatic model building. This paper presents an automated modeling approach from an existing design database using the example of a network analysis for building automation fieldbuses. The analysis is based on an analytical decomposition approach that enables fast estimation of performance measures for large-scale networks. The combination of fast analytical algorithms with automatic model generation allows network performance engineering with minimized effort for model generation and analysis.

Designing dependable storage solutions for shared application environments

Abstract: The costs of data loss and unavailability can be large, so businesses use many data protection techniques, such as remote mirroring, snapshots and backups, to guard against failures. Choosing an appropriate combination of techniques is difficult because there are numerous approaches for protecting data and allocating resources. Storage system designers typically use ad hoc techniques, often resulting in over-engineered, expensive solutions or under-provisioned, inadequate ones. In contrast, this paper presents a principled, automated approach for designing dependable storage solutions for multiple applications in shared environments. Our contributions include search heuristics for intelligently exploring the large design space and modeling techniques for capturing interactions between applications during recovery. Using realistic storage system requirements, we show that our design tool can produce designs that cost up to 3X less in initial outlays and expected data penalties than the designs produced by an emulated human design process.

Design of Contoured Microscale Thermomechanical Actuators

Abstract: In this paper, we disclose how to contour the beams of microscale thermomechanical actuators (TMAs) in order to enhance the actuator's thermal and mechanical performance. In this approach, we vary the cross-section of the heated beams over the length of the beams. Using this approach, the stored strain energy and axial stiffness of the beam may be modified to achieve an optimized force-displacement relationship. Examples are provided to show that in some designs: 1) the maximum achievable thermal strain of a driving beam may be increased by 29%, 2) actuator stroke may be increased by a factor of four, and 3) identical force or displacement characteristics may be achieved with a 90% reduction in power. This paper presents the theory and models used to predict the thermal and mechanical behavior of the actuator. The theory and models were used to create a deterministic link between the actuator's design parameters and the actuator's performance characteristics. The theory and models were combined within a design tool that is posted at http://pcsl.mit.edu. The tool has been used to generate performance plots that enable designers to: 1) understand the quantitative relationships between design parameters and performance and 2) rapidly converge upon first-pass design parameters.1695

MES - a web-based design tool for microwave engineering

Abstract: Microwave engineering often involves extensive circuit analysis and design, typically requiring precise calculations. To expedite the handling of complicated design calculations, a Web-based design tool named Microwave Engineering Solutions (MES) was developed as a graduate student project in the Electrical and Computer Engineering Department at North Dakota State University (NDSU), Fargo, and is described in this paper. JavaScript, PHP, and Perl were used to develop MES, which consists of three design tools: 1) FilTech*a design tool for analog filters, 2) LMatch*a design tool for impedance matching, and 3) MicroLines*a design tool for striplines and microwave network analysis. MES is used by Electrical and Computer Engineering (ECE) students studying various aspects of electromagnetics and is freely available on the Web via the link at http://venus.ece.ndsu.nodak.edu//spl sim/ronelson/MESLink/index.html.

A Turbomachinery Design Tool for Teaching Design Concepts for Axial-Flow Fans, Compressors, and Turbines

Abstract: A new turbomachinery design system, T-AXI, is described and demonstrated. It is intended primarily for use by educators and students, although it is sophisticated enough for actual designs. The codes, example cases and a user’s manual are available through the authors’ web sites. The design system can be used to design multistage compressors and turbines from a small number of physical design parameters. Students can understand the connection between these physical parameters such as Mach number and flow angles to the cross sectional area and angular momentum. There is also a clear connection between the angular momentum, work and blade loadings. Loss models are built-in and results are compared against tested geometries. The code also has a built-in blade geometry generator and the geometry can be output for running the MISES blade-to-blade solver on each section or visualizing the blades. A single stage compressor from the US Air Force Stage Matching Investigation rig, the 10 stage NASA/GE EEE high pressure compressor and the NASA/GE EEE 5 stage low pressure turbine have been used to validate T-AXI as a design tool.© 2006 ASME

Multidisciplinary Design Optimization for Aeromechanics and Handling Qualities

Abstract: A design optimization study is presented in which rotor dynamics and flight dynamics are simultaneously taken into account to maximize the damping of a rotor lag mode. The design variables include rotor, airframe, and flight control system parameters. The constraints address rotor stability and loads and handling qualities. Two design optimization cases are considered, one with only constraints computed from the linearized model of the helicopter and the other with additional constraints that require the integration of the nonlinear equations of motion. Both finite difference and semi-analytical gradients are used for some constraints. The optimization procedure increases the lag mode damping by up to 90%, while satisfying all of the constraints, primarily by reducing the blade torsion stiffness. The aeromechanic design problem is a multidisciplinary problem. The constraint active at the optimum is the level 1 handling qualities requirement in the pitch axis. Optimization provides a framework to manage multidisciplinary problems systematically and efficiently. Using semi-analytical gradients of the constraints computed from the linearized model yields the same results as with finite difference gradients, but more efficiently. The computational advantage increases with problem size. Further advances in computer hardware and in optimization algorithms, including efficient sensitivity analyses, will help make numerical optimization a practical design tool.

Tailored fibre placement optimization tool

Abstract: European aircraft industry demands for reduced development and operating costs. Tailored Fibre Placement (TFP) is a promising technology which contributes to this aim by reducing structural weight at safe design; it exploits considerable reserves in structures made of Carbon Fibre Reinforcement Plastics (CFRP) by placing the carbon fibre rovings according principal stresses. This paper deals with selected results of 4 research projects in the field of TFP the Institute of Composite Structures and Adaptive Systems of DLR is working in. Within the first already finished project the tool TACO (Tailored Composite Design Code), which is a TFP design tool for lightweight aerospace structures, was developed. Three running follow-up projects deal with basic research investigations, improvement of TACO and its industrial application as well as the automatic determination of the roving distributions.

Transonic Airfoil Shape Optimization in Preliminary Design Environment

Abstract: A modified profile optimization method using a smoothest shape modification strategy (POSSEM) is developed for airfoil shape optimization in a preliminary design environment. POSSEM is formulated to overcome two technical diculties frequently encountered when conducting multipoint airfoil optimization within a high-resolution design space: the generation of undesirable optimal airfoil shapes due to high frequency components in the parametric geometry model and significant degradation in the o-design performance. To demonstrate the usefulness of POSSEM in a preliminary design environment, a design competition was conducted with the objective of improving a fairly well-designed baseline airfoil at four transonic flight conditions without incurring any o-design performance degradation. Independently, two designs were generated from the inverse design tool CDISC, while a third design was generated from POSSEM using over 200 control points of a cubic B-spline curve representation of the airfoil as design variables for the shape optimization. Pros and cons of all the airfoil designs are documented along with in-depth analyses of simulation results. The POSSEM design exhibits a fairly smooth curvature and no degradation in the o-design performance. Moreover, it has the lowest average drag among the three designs at the design conditions, as evaluated from three dierent flow solvers. This study demonstrates the potential of POSSEM as a practical airfoil optimization tool for use in a preliminary design environment. The novel ideas used in POSSEM, such as the smoothest shape modification and modified profile optimization strategies, are applicable to minimizing aircraft drag at multiple flight conditions.

Integrated Research and Development Environment for Real-Time Distributed Embodied Intelligent Systems

Abstract: In the field of intelligent systems, research and design approaches vary from predefined architectures to self-organizing systems. Regardless of the architectural approach, such systems may grow in size and complexity to levels where the capacities of people are strongly challenged. Such systems are commonly researched, designed and developed following several methods and with the help of a variety of software tools. In this paper we want to describe our research and development environment. It is composed of a set of tools that support our research and enable us to develop large scale intelligent systems used in our robots and in our test platforms. The main parts of our research and development environment are: the component models BBCM (Brain Bytes Component Model) and BBDM (Brain Bytes Data Model), the Middleware RTBOS (Real-Time Brain Operating System), the Monitoring system CMBOS (Control-Monitor Brain Operating System) and the Design Environment DTBOS (Design Tool for Brain Operating System). We will compare our research and development environment with others available on the market or still in research phase and we will describe some of our experiments.

Integration of friction stir welding into a multi-disciplinary aerospace design framework

Abstract: Multidisciplinary design and innovative highly automated manufacturing methods are increasingly important to today's aircraft industry: multidisciplinary design because it reduces lead-time and results in a better design, and automated manufacturing methods because they are more capable and reduce manufacturing cost. In this paper a cost estimation model is presented that integrates the manufacturing cost of friction stir welded connections within a multidisciplinary design decision tool. Due to the fact that friction stir welding is a new manufacturing method, the cost estimation model is based on the actual process physics, meaning what the process looks like in terms of processing speeds and characteristics. As an integral part of a multidisciplinary design framework, the developed cost estimation model contributes to a design support tool that assesses not only manufacturing but also structural and aerodynamic issues. It is shown that the cost model developed can be integrated into this more holistic design process support architecture. The predicted costs are accurate to the historical data and allow tradeoff of manufacturing and economic considerations within the context of the multidisciplinary design tool. The tradeoff capability is highlighted through a presented case study that compares the friction stir welding process as an alternative solution to more tradition riveting. Most importantly, this results in a quantitative tradeoff between two processes that shows the manufacturing cycle time of friction stir welding to be reduced by 60% and the recurring assembly cost by 20%.