Showing papers on "Conceptual design published in 1979"

Cognitive Strategies in Architectural Design

Abstract: The paper describes one of the series of experiments studying the nature of the architectural design process and how design skills are acquired by students. An experimental situation is described which models some central features of design problems in the abstract. This allows comparisons to be made between groups of first and final year students of architecture as well as sixth form school pupils and post-graduate science students. Significantly different problem solving strategies are shown by the final year architecture and post-graduate science students. It is suggested that these results have implications for the nature of design legislation, design tools and particularly computer aided design systems, many of which currently in use appear to be based on the scientists' rather than designers' cognitive strategies.

NUWMAK: a tokamak reactor design study. [Conceptual design report]

Abstract: Detailed design information is given on the NUWMAK in each of the following chapters: (1) design philosophy of NUWMAK, (2) overview and summary of the NUWMAK design study, (3) summary of parameters, (4) plasma analysis, (5) rf heating system, (6) magnet system and energy storage, (7) blanket design, (8) neutronics analysis and radioactivity, (9) materials analysis, (10) tritium systems, (11) assembly and maintenance, (12) balance of plant, (13) materials resource analysis, and (14) system economics (MOW)

Reliability Based Criteria for Reinforced Concrete Design

Abstract: Probabilistic limit states design concepts have evolved over the past decade because of the potential that they afford for simplifying the design process and placing it on a consistent basis for various construction materials. Several different criteria formats have been proposed, which have the common feature that their various load and resistance factors have a reliability basis. Two such criteria for reinforced concrete design are examined in this paper. The development of practical reliability based design criteria is also illustrated. While these are consistent with appropriate measures of design uncertainty and reliability and have a well-established rationale, they retain the simple characteristics of existing criteria with which designers in the United States feel comfortable.

Conceptual design of thermal energy storage systems for near-term electric utility applications. Final report

Abstract: A detailed evaluation is made of TES through a careful screening, analysis, conceptual design, and evaluation to determine if it can meet the peak power needs of electric utilities for near-term applications Primary emphasis is on electric utilities developing new plants, planned and designed to incorporate the TES The new plants considered are conventional coal and nuclear fueled, which represent the large majority of expected electric utility capacity additions between now and AD 2000 As nuclear plants, only light water reactors are considered; as coal-fired plants, only conventional types with flue gas desulfurization when high-sulfur coal is to be burned are considered All plants employ a steam-driven turbogenerator for conversion to electricity and a fired boiler or nuclear reactor as a steam supply

Design Optimization of RTG for Solar-Polar Mission

Abstract: The paper presents the conceptual design of an RTG, employing stacked radioisotope heat source modules and silicon-germanium thermo-electric couples, for use on the joint NASA/ESA International Solar-Polar Mission. It describes a computer program which, for a given set of assumptions and ground rules, can rapidly examine thousands of design variations and determine the combination of design parameters which will minimize the RTG weight for a given power output. Graphical results are presented to illustrate design trends and clarify the optimization procedure. The generated results lead to interesting and somewhat unexpected conclusions about optimum design parameters, the relative constancy of RTG specific power over a wide power range, comparisons between single and split RTGs, sensitivity to variations in heat source module design, weight comparisons with the MHW RTG, and comparative RTG weights for different housing and radiator fin materials. There are three copies in the file.

Operator Station Design System: A Computer Aided Design Approach to Work Station Layout

Abstract: The Operator Station Design System is resident in NASA's Johnson Space Center Spacecraft Design Division Design Performance Laboratory. It includes stand-alone mini-computer hardware and Panel Layout Automated Interactive Design and Crew Station Assessment of Reach software. The data base consists of the Shuttle Transportation System Orbiter Crew Compartment (in part), the Orbiter payload bay and remote manipulator (in part), and various anthropometric populations. The system is utilized to provide panel layouts, assess reach and vision, determine interference and fit problems early in the design phase, study design applications as a function of anthropometric and mission requirements, and to accomplish conceptual design to support advanced study efforts.

Conceptual Design of a Flywheel Energy Storage System.

Abstract: : A conceptual design of a flywheel energy storage system suitable for on-site interfacing with residential photovoltaic (PV) energy sources has been developed. The basic design objective was to provide a generous margin of safety and above average reliability and efficiency at the lowest practical cost. This report describes the basic design concept and the general approach to the conceptual design of the energy storage system. The basic concept to interface with PV energy sources utilizes a constant voltage motor/generator directly coupled to a flywheel rotor. The voltage level of the motor is maintained at the optimum operating voltage of the array of PV cells and permits peak power tracking. Power is withdrawn from the flywheel-driven generator when the voltage output of the array drops below its optimum value, and power is delivered to the flywheel via the generator (then operating as a motor) when the voltage rises above the optimum value. A variety of motor types and flywheel rotor types has been studied to arrive at a conceptual design to meet the program objectives. A fiber-composite rotor driving a separately-excited motor satisfies the basic requirements. To obtain acceptable efficiency and low run-down losses, the flywheel operates in a vacuum and has a combination of magnetic thrust support and ball bearings to reduce bearing friction in an economical fashion. The need for rotary vacuum seal is eliminated by the use of a hermetically-sealed magnetic power coupling. (MM)

Conceptual design of a large heavy water reactor for US siting

Abstract: Information on the PHWR type reactor is presented concerning design characteristics; fuel management and resource utilization; economic evaluations; safety, licensing, and environmental impact; and commercial introduction.

CADAM" Data Handling from Conceptual Design through Product Support

Abstract: The use of interactive computer graphics for data handling in aircraft design, manufacturing, and product support is discussed. The software used is the Lockheed-California Company Computer-graphics Augmented Design and Manufacturing (CADAM) system and the Independent Research and Development program CADATA. Starting with the conceptual design three view on CAD AM, configuration geometry is then available through CADATA for use by the analytic users for developing the design to achieve the desired performance and cost. CADAM provides a common data base of the selected vehicle design for all user disciplines: preliminary design, loft, production design, tool design, numerical control part programming, quality control, and product support. Examples of the use of CADAM and CADATA are given to illustrate the cost savings and reduced time spans achieved.

Conceptual design of a large Spectral Shift Controlled Reactor

Abstract: Within the framework of the Nonproliferation Alternative Systems Assessment Program (NASAP), the US Department of Energy (DOE) has sponsored the development of a conceptual design of a large Spectral Shift Controlled Reactor (SSCR). The results are presented of the development program, and the performance of the conceptual SSCR is assessed on the basis of fuel resource utilization and total power costs. The point of departure of the design study was a 1270 MW(e) PWR using Combustion Engineering's System 80 reactor and Stone and Webster's Reference Plant Design. The initial phase of the study consisted of establishing an optimal core design for both the once-through uranium cycle and the denatured U-235/thorium cycle with uranium recycle. The performance of the SSCR was then also assessed for the denatured U-233/thorium cycle with uranium recycle and for the plutonium/thorium cycle with plutonium recycle. After the optimal core design was established, the design of the NSSS and balance of plant was developed.

Reactor design for nuclear electric propulsion

Abstract: The paper analyzes the consequences of heat pipe failures, that resulted in modifications to the basic design of a heat-pipe cooled, fast spectrum nuclear reactor and led to consideration of an entirely different core design. The new design features an integral laminated core configuration consisting of alternating layers of UO2 and molybdenum sheets that span the diameter of the core. Design characteristics are presented and compared for two reactors. A conceptual design for a heat exchanger between the core and the thermionic converter assembly is described. This heat exchanger would provide design and fabrication decoupling of these two assemblies.

Dynamic Materials Accounting in the Back End of the Light Water Reactor Fuel Cycle

Abstract: The US Department of Energy Office of Safeguards and Security is sponsoring the development of advanced safeguards systems for future industrial-scale nuclear fuel cycle plants. As part of this program, the Los Alamos Scientific Laboratory is engaged in conceptual design studies of integrated safeguards systems incorporating near-real-time (dynamic) materials accounting. Preliminary designs of advanced accounting systems have been completed for chemical separations, nitrate-to-oxide conversion, and mixed-oxide fuel refabrication processes. The proposed accounting systems combine current materials balance accounting methods with modern on-line measurement, data base management, and data analysis technologies. The results of these studies indicate that special nuclear materials can be safeguarded effectively in large-scale fuel cycle facilities. The design methodology and the insights gained from these studies are essential for the design of specific fuel cycle facilities and provide general design criteria to those planning such facilities. 10 figures, 10 tables.

Concepts for a bottom-mounted buoyant, stab-in cold water pipe for the OTEC program

Abstract: A conceptual design for a bottom-mounted, stab-in cold water pipe (CWP) for OTEC is presented. The design concepts used are based on experience gained in the design of marine risers for offshore petroleum production. After a detailed description of the system envisioned and the installation scenario, the status of the major components in the system is discussed relative to the present state of the art in the oil industry. From preliminary structural analyses and cost projections, a comparison is then drawn between the bottom-mounted pipe and free-hanging CWP designs. The comparison shows the bottom-mounted concept to be technically and economically sound, utilizing present oil industry design practices. Finally, recommendations are made for further work to integrate the bottom-mounted CWP concept into the OTEC program.

Orbiting deep space relay station study. Volume 2: Conceptual design

Abstract: The Orbiting Deep Space Relay Station conceptual design is described. The baseline for implementation cost and schedule estimates is also described.

Master control and Data Acquisition System for a Solar Central Receiver Electric Power Plant

Abstract: Describes the conceptual design arrived at through a US Department of Energy sponsored two-year research and development program to design the 10 MW electric Solar Central Receiver Power Plant currently under construction in Barstow, California. The Circuits and Systems concepts related to the Master Control and Data Acquisition Systems are emphasized.

A Conceptual Design of a Lighter-than-Air Test and Research Vehicle.

Abstract: : An analysis of conventional lighter-than-air vehicles was conducted to determine if a modular design approach was feasible. Once this was accomplished, a conceptual design using the modular approach is presented for a vehicle to serve as a platform for conducting lighter-than-air flight tests and research. In addition, a general discussion is included on the program management organization, flight tests, and instrumentation of such a vehicle. (Author)

An economic analysis of a commercial approach to the design and fabrication of a space power system

Abstract: A commercial approach to the design and fabrication of an economical space power system is presented. Cost reductions are projected through the conceptual design of a 2 kW space power system built with the capability for having serviceability. The approach to system costing that is used takes into account both the constraints of operation in space and commercial production engineering approaches. The cost of this power system reflects a variety of cost/benefit tradeoffs that would reduce system cost as a function of system reliability requirements, complexity, and the impact of rigid specifications. A breakdown of the system design, documentation, fabrication, and reliability and quality assurance cost estimates are detailed.