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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 73 records · Page 4

Use of constrained optimization in the conceptual design of a medium-range subsonic transport

Constrained parameter optimization was used to perform the optimal conceptual design of a medium range transport configuration. The impact of choosing a given performance index was studied, and the required income for a 15 percent return on investment was proposed as a figure of merit. A number of design constants and constraint functions were systematically varied to document the sensitivities of the optimal design to a variety of economic and technological assumptions. A comparison was made for each of the parameter variations between the baseline configuration and the optimally redesigned configuration.

Sliwa, S. M.↗

Sensitivity of the optimal preliminary design of a transport to operational constraints and performance index

Constrained parameter optimization was used to perform the optimal preliminary design of a medium range transport configuration. The impact of choosing a performance index was studied and the required fare for a 15 percent return-on-investment was proposed as a figure-of-merit. A number of design constants and constraint functions were systematically varied to document the sensitivities of the optimal design to a variety of economic and technological assumptions. Additionally, a comparison is made for each of the parameter variations between the baseline configuration and the optimally redesigned configuration.

Sliwa, S. M.↗

Current economic and sensitivity analysis for ID slicing of 4 inch and 6 inch diameter silicon ingots for photovoltaic applications

The economics and sensitivities of slicing large diameter silicon ingots for photovoltaic applications were examined. Current economics and slicing add on cost sensitivities are calculated using variable parameters for blade life, slicing yield, and slice cutting speed. It is indicated that cutting speed has the biggest impact on slicing add on cost, followed by slicing yield, and by blade life as the blade life increases.

Roberts, E. G.↗

Procedure for generating global atmospheric engine emissions data from future supersonic transport aircraft. The 1990 high speed civil transport studies

The input for global atmospheric chemistry models was generated for baseline High Speed Civil Transport (HSCT) configurations at Mach 1.6, 2.2, and 3.2. The input is supplied in the form of number of molecules of specific exhaust constituents injected into the atmosphere per year by latitude and by altitude (for 2-D codes). Seven exhaust constituents are currently supplied: NO, NO2, CO, CO2, H2O, SO2, and THC (Trace Hydrocarbons). An eighth input is also supplied, NO(x), the sum of NO and NO2. The number of molecules of a given constituent emitted per year is a function of the total fuel burned by a supersonic fleet and the emission index (EI) of the aircraft engine for the constituent in question. The EIs for an engine are supplied directly by the engine manufacturers. The annual fuel burn of a supersonic fleet is calculated from aircraft performance and economic criteria, both of which are strongly dependent on basic design parameters such as speed and range. The altitude and latitude distribution of the emission is determined based on 10 Intern. Air Transport Assoc. (IATA) regions chosen to define the worldwide route structure for future HSCT operations and the mission flight profiles.

Sohn, R. A.↗

RL-10 Based Combined Cycle For A Small Reusable Single-Stage-To-Orbit Launcher

This paper discusses a new application of the combined propulsion known as the KLIN(TM) cycle, consisting of a thermally integrated deeply cooled turbojet (DCTJ) and liquid rocket engine (LRE). If based on the RL10 rocket engine family, the KLIN (TM) cycle makes a small single-stage-to-orbit (SSTO) reusable launcher feasible and economically very attractive. Considered in this paper are the concept and parameters of a small SSTO reusable launch vehicle (RLV) powered by the KLIN (TM) cycle (sSSTO(TM)) launcher. Also discussed are the benefits of the small launcher, the reusability, and the combined cycle application. This paper shows the significant reduction of the gross take off weight (GTOW) and dry weight of the KLIN(TM) cycle-powered launcher compared to an all-rocket launcher.

Balepin, Vladimir↗

SPS-ALPHA: The First Practical Solar Power Satellite via Arbitrarily Large Phased Array

The vision of delivering solar power to Earth from platforms in space has been known for decades. However, early architectures to accomplish this vision were technically complex and unlikely to prove economically viable. Some of the issues with these earlier solar power satellite (SPS) concepts – particularly involving technical feasibility – were addressed by NASA’s space solar power (SSP) studies and technology research in the mid-to-late 1990s. Despite that progress, ten years ago a number of key technical and economic uncertainties remained. A new SPS concept has been proposed that resolves many, if not all, of those uncertainties: “SPSALPHA” (Solar Power Satellite by means of Arbitrarily Large Phased Array). During 2011-2012 the NASA Innovative Advanced Concepts (NIAC) Program supported a Phase 1 “SPS-ALPHA” project, the goal of which was to establish the technical and economic viability of the SPS-ALPHA concept to an early TRL 3 – analytical proof-of-concept – and provide a framework for further study and technology development. The objectives of this project were to: (1) conduct an initial end-to-end systems analysis of the SPS-ALPHA concept in order to determine its technical feasibility; (2) identify and assess in greater detail the key technology challenges inherent in the architecture (including figures of merit for each critical technology area); (3) conduct an initial evaluation of the economic viability of the concept (as a function of key performance parameters); and, (4) define a preliminary roadmap for the further development of the SPS-ALPHA concept.

Mankins, John↗

Solar energy system economic evaluation for IBM System 3, Glendo, Wyoming

This analysis was based on the technical and economic models in f-chart design procedures with inputs based on the characteristics of the parameters of present worth of system cost over a projected twenty year life: life cycle savings, year of positive savings, and year of payback for the optimized solar energy system at each of the analysis sites. The sensitivity of the economic evaluation to uncertainties in constituent system and economic variables was also investigated.

Source record↗

Optimal regime and conditioning time of transistors for equipment with increased reliability

It is shown that an economically justified choice of regime and conditioning time for transistors for equipment of increased reliability is impossible without analyzing the stabilization time of the transistor parameters. The optimal regime and conditioning time are well founded. A method is presented for evaluating the optimal conditioning time by technical economic indexes.

Breslavets, A. V.↗

Solar energy system economic evaluation for Solaron Akron, Akron, Ohio

The economic analysis of the solar energy system that was installed at Akron, Ohio is developed for this and four other sites typical of a wide range of environmental and economic conditions. The analysis is accomplished based on the technical and economic models in the f chart design procedure with inputs based on the characteristics of the installed parameters of present worth of system cost over a projected twenty year life: life cycle savings, year of positive savings and year of payback for the optimized solar energy system at each of the analysis sites. The sensitivity of the economic evaluation to uncertainties in constituent system and economic variables is also investigated. Results show that only in Albuquerque, New Mexico, where insolation is 1828 Btu/sq ft/day and the conventional energy cost is high, is this solar energy system marginally profitable.

Source record↗

Computerized atmospheric trace contaminant control simulation for manned spacecraft

Buildup of atmospheric trace contaminants in enclosed volumes such as a spacecraft may lead to potentially serious health problems for the crew members. For this reason, active control methods must be implemented to minimize the concentration of atmospheric contaminants to levels that are considered safe for prolonged, continuous exposure. Designing hardware to accomplish this has traditionally required extensive testing to characterize and select appropriate control technologies. Data collected since the Apollo project can now be used in a computerized performance simulation to predict the performance and life of contamination control hardware to allow for initial technology screening, performance prediction, and operations and contingency studies to determine the most suitable hardware approach before specific design and testing activities begin. The program, written in FORTRAN 77, provides contaminant removal rate, total mass removed, and per pass efficiency for each control device for discrete time intervals. In addition, projected cabin concentration is provided. Input and output data are manipulated using commercial spreadsheet and data graphing software. These results can then be used in analyzing hardware design parameters such as sizing and flow rate, overall process performance and program economics. Test performance may also be predicted to aid test design.

Perry, J. L.↗

Reward and uncertainty in exploration programs

A set of variables which are crucial to the economic outcome of petroleum exploration are discussed. These are treated as random variables; the values they assume indicate the number of successes that occur in a drilling program and determine, for a particular discovery, the unit production cost and net economic return if that reservoir is developed. In specifying the joint probability law for those variables, extreme and probably unrealistic assumptions are made. In particular, the different random variables are assumed to be independently distributed. Using postulated probability functions and specified parameters, values are generated for selected random variables, such as reservoir size. From this set of values the economic magnitudes of interest, net return and unit production cost are computed. This constitutes a single trial, and the procedure is repeated many times. The resulting histograms approximate the probability density functions of the variables which describe the economic outcomes of an exploratory drilling program.

Kaufman, G. M.↗

Economic evaluation of flying-qualities design criteria for a transport configured with relaxed static stability

Direct constrained parameter optimization was used to optimally size a medium range transport for minimum direct operating cost. Several stability and control constraints were varied to study the sensitivity of the configuration to specifying the unaugmented flying qualities of transports designed to take maximum advantage of relaxed static stability augmentation systems. Additionally, a number of handling qualities related design constants were studied with respect to their impact on the design.

Sliwa, S. M.↗

Methods of determining electron concentrations in the magnetosphere from nose whistlers

Whistler propagation in the magnetosphere was studied in detail to find accurate and economical means of determining the path latitude and the electron concentration along the path from whistler parameters of nose frequency and travel time at the nose. Longitudinal propagation in field aligned whistler ducts of cold plasma was assumed, and the earth's magnetic field was approximated by a centered dipole. The effects of whistler propagation in the earth-ionosphere waveguide and through the conjugate ionospheres were treated as small perturbations. Several alternative methods are described so that the most economical method may be chosen depending on the desired accuracy and the availability of a computer or a calculator.

Park, C. G.↗

An Integrated Economics Model for ISRU in Support of a Mars Colony - Initial Status Report

The aim of this effort is to develop an integrated set of risk-based financial and technical models to evaluate multiple Off-Earth Mining (OEM) scenarios. This quantitative, scenario- and simulation-based tool will help identify combinations of market variables, technical parameters, and policy levers that will enable the expansion of the global economy into the solar system and return economic benefits. Human ventures in space are entering a new phase in which missions formerly driven by government agencies are now being replaced by those led by commercial enterprises - in launch, satellite deployment, resupply of the International Space Station, and space tourism. In the not-too-distant future, commercial opportunities will also include the mining of asteroids, the Moon, and Mars. This investigation will examine the role of OEM in a growing space economy. (In this investigation, the term 'mining' is taken to embrace minerals, ice/water, and other in situ resources.) OEM can be the engine that drives the space economy, so it would be useful to understand what OEM market conditions and technology requirements are needed for that economy to prosper. These specific elements will be studied in the wider context of creating an economy that could ultimately support a sustainable Mars Colony. Such a colony will need in situ resources not only for its own survival, but to prosper and grow, it must create viable business ventures, essentially by fulfilling the demand for in situ resources from and on Mars. This investigation will focus on understanding the role and economic prospect for OEM associated with the Human Colonization of Mars (HCM).

architecture framework↗

Assessment of an analytical procedure for predicting supersonic ejector nozzle performance

The ability of analysis to predict ejector nozzle characteristics over a wide range of conditions and to study the relation between design parameters and performance is assessed. The analytical method investigated provided an accurate and economical method for predicting the performance of supersonic ejector nozzles. The factors which had the greatest influence over ejector nozzle behavior were those which influenced the initial expansion and recompression process.

Anderson, B. H.↗

A unifying strain criterion for fracture of fibrous composite laminates

Fibrous composite materials, such as graphite/epoxy, are light, stiff, and strong. They have great potential for reducing weight in aircraft structures. However, for a realization of this potential, designers will have to know the fracture toughness of composite laminates in order to design damage tolerant structures. In connection with the development of an economical testing procedure, there is a great need for a single fracture toughness parameter which can be used to predict the stress-intensity factor (K(Q)) for all laminates of interest to the designer. Poe and Sova (1980) have derived a general fracture toughness parameter (Qc), which is a material constant. It defines the critical level of strains in the principal load-carryng plies. The present investigation is concerned with the calculation of values for the ratio of Qc and the ultimate tensile strain of the fibers. The obtained data indicate that this ratio is reasonably constant for layups which fail largely by self-similar crack extension.

Poe, C. C., Jr.↗

Value of Landsat in urban water resources planning

The reported investigation had the objective to evaluate the utility of satellite multispectral remote sensing in urban water resources planning. The results are presented of a study which was conducted to determine the economic impact of Landsat data. The use of Landsat data to estimate hydrologic model parameters employed in urban water resources planning is discussed. A decision regarding an employment of the Landsat data has to consider the tradeoff between data accuracy and cost. Bayesian decision theory is used in this connection. It is concluded that computer-aided interpretation of Landsat data is a highly cost-effective method of estimating the percentage of impervious area.

Jackson, T. J.↗

On designing for quality

The problem of ensuring the required quality of products and/or technological processes often becomes more difficult due to the fact that there is not general theory of determining the optimal sets of value of the primary factors, i.e., of the output parameters of the parts and units comprising an object and ensuring the correspondence of the object's parameters to the quality requirements. This is the main reason for the amount of time taken to finish complex vital article. To create this theory, one has to overcome a number of difficulties and to solve the following tasks: the creation of reliable and stable mathematical models showing the influence of the primary factors on the output parameters; finding a new technique of assigning tolerances for primary factors with regard to economical, technological, and other criteria, the technique being based on the solution of the main problem; well reasoned assignment of nominal values for primary factors which serve as the basis for creating tolerances. Each of the above listed tasks is of independent importance. An attempt is made to give solutions for this problem. The above problem dealing with quality ensuring an mathematically formalized aspect is called the multiple inverse problem.

Vajingortin, L. D.↗