Generalized approach to the thermal analysis of orbiting spacecraft.
Explorer 40 satellite mathematical model and verification testing for close spacecraft flight temperature predictions
Greene, R. F., Jr.↗
SEARCH · Engineering Papers
Results for “analysis approach”
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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A unified approach to the error analysis of position finding techniques
Error analysis of position finding techniques using analytical model composed of equations describing position error differential relationships
Casserly, G. W.↗
System implementation and operations session: Classification and mensuration, an approach to LANDSAT data analysis for crop identification
There are no author-identified significant results in this report.
Biffell, R.↗
An economic analysis of a commercial approach to the design and fabrication of a space power system
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.
Putney, Z.↗
An evolutionary approach to the group analysis of global geophysical data
The coordinated data analysis that developed within the International Magnetospheric Study is presented. A tracing of its development along with various activities taking place within this framework are reported.
Vette, J. I.↗
An economic analysis of a commercial approach to the design and fabrication of a space power system
This paper discusses a commercial approach to the design and fabrication of an economical space power system. With the advent of the space shuttle, steps can be taken to back away from the presently used space qualified approach in order to reduce cost of space hardware by incorporating, where possible, commercial design, fabrication, and quality assurance methods. 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 has been 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.
Putney, Z.↗
Commercial transport aircraft composite structures
The role that analysis plays in the development, production, and substantiation of aircraft structures is discussed. The types, elements, and applications of failure that are used and needed; the current application of analysis methods to commercial aircraft advanced composite structures, along with a projection of future needs; and some personal thoughts on analysis development goals and the elements of an approach to analysis development are discussed.
Mccarty, J. E.↗
A travelling wave approach to the dynamic analysis of large space structures
This paper investigates the dynamic analysis of certain large space structures via travelling wave mathematics. It is assumed that large space structures may be modelled as networks of interconnected one-dimensional structural members. Bodies with a finite number of internal dynamic degrees of freedom may be scattered throughout the network. The wave propagation behavior of one-dimensional continuous and periodic structural elements is investigated. A scattering matrix description of junctions and discontinuities is proposed. A time domain method of calculating network transient response using the wave propagation characteristics of the elements is briefly described.
Von Flotow, A. H.↗
Component-specific modeling
The ability to accurately structurally analyze engine components to assure that they can survive for their designed lifetime in an increasingly harsh environment is discussed. Under the HOST (HOt Section Technology) program, advanced component-specific modeling methods, with built-in analysis capability, will be developed separately for burner liners, turbine blades and vanes. These modeling methods will make maximum use of, but will not rely solely on, existing analysis methods and techniques, to analyze the three identified components. Nor will the complete structural analysis of a component necessarily be performed as a single analysis. The approach to be taken will develop complete software analysis packages with internal, component-specific, self-adaptive solution strategies. Each package will contain a set of modeling and analysis tools. The selection and order of specific methods and techniques within the set to be applied will depend on the specific-component, the current thermo-mechanical loading, and the current state of the component. All modeling and analysis decisions will be made internally based on developed decision criteria within the solution strategies; minimal user intervention will be required.
Hirschbein, M. S.↗
A system approach to design-analysis
Today, the increased use of Finite Element Analysis coupled with computer graphics interfaces presents the analyst with many alternatives. The drive toward automation has resulted in the creation of many modeling and post-processing systems that are in use today throughout the world. Many of these systems exist as islands of technology. The need for fully integrated systems is being met by many companies today.
White, G.↗
Operator function modeling: An approach to cognitive task analysis in supervisory control systems
In a study of models of operators in complex, automated space systems, an operator function model (OFM) methodology was extended to represent cognitive as well as manual operator activities. Development continued on a software tool called OFMdraw, which facilitates construction of an OFM by permitting construction of a heterarchic network of nodes and arcs. Emphasis was placed on development of OFMspert, an expert system designed both to model human operation and to assist real human operators. The system uses a blackboard method of problem solving to make an on-line representation of operator intentions, called ACTIN (actions interpreter).
Mitchell, Christine M.↗
A parametric approach to hover balance analysis of two STOVL fighter concepts
Successful development of an aircraft with vertical landing capability must address the critical problem of balancing the aircraft for hover. In this paper a parametric method for balancing short takeoff and vertical landing (STOVL) aircraft in hover is described and applied to the analysis of two conceptual STOVL fighters. One uses a remote augmented lift system and the other a thrust-vectoring hybrid tandem-fan engine.
Samuels, Jeffrey J.↗
An algorithmic approach to crustal deformation analysis
In recent years the analysis of crustal deformation measurements has become important as a result of current improvements in geodetic methods and an increasing amount of theoretical and observational data provided by several earth sciences. A first-generation data analysis algorithm which combines a priori information with current geodetic measurements was proposed. Relevant methods which can be used in the algorithm were discussed. Prior information is the unifying feature of this algorithm. Some of the problems which may arise through the use of a priori information in the analysis were indicated and preventive measures were demonstrated. The first step in the algorithm is the optimal design of deformation networks. The second step in the algorithm identifies the descriptive model of the deformation field. The final step in the algorithm is the improved estimation of deformation parameters. Although deformation parameters are estimated in the process of model discrimination, they can further be improved by the use of a priori information about them. According to the proposed algorithm this information must first be tested against the estimates calculated using the sample data only. Null-hypothesis testing procedures were developed for this purpose. Six different estimators which employ a priori information were examined. Emphasis was put on the case when the prior information is wrong and analytical expressions for possible improvements under incompatible prior information were derived.
Iz, Huseyin Baki↗
An expert system approach to astronomical data analysis
Expert systems technology has much to offer to the problem of astronomical data analysis, where large data volumes and sophisticated analysis goals have caused a variety of interesting problems to arise. The construction of a prototype expert system whose target domain is CCD image calibration, is reported. The prototype is designed to be extensible to different and more complex problems in a straighforward way, and to be largely independent of the details of the specific data analysis system which executes the plan it generates.
Johnston, Mark D.↗
An approximate methods approach to probabilistic structural analysis
A probabilistic structural analysis method (PSAM) is described which makes an approximate calculation of the structural response of a system, including the associated probabilistic distributions, with minimal computation time and cost, based on a simplified representation of the geometry, loads, and material. The method employs the fast probability integration (FPI) algorithm of Wu and Wirsching. Typical solution strategies are illustrated by formulations for a representative critical component chosen from the Space Shuttle Main Engine (SSME) as part of a major NASA-sponsored program on PSAM. Typical results are presented to demonstrate the role of the methodology in engineering design and analysis.
Mcclung, R. C.↗
Application of the TRANAIR rectangular grid approach to the aerodynamic analysis of complex configurations
A numerical method is described which uses a rectangular grid to solve the nonlinear full potential equation about complex configurations. The grid is locally refined to resolve high velocity gradients arising from leading edge expansions or shock waves. The grid penetrates the boundary (described by networks of quadrilateral panels) and is generated automatically. Discrete operators are constructed using the finite element method. The system of nonlinear discrete equations is solved iteratively using a Krylov subspace method preconditioned by an exterior Poisson solver and a direct sparse solver. The primary emphasis is to provide design engineers with an aerodynamic analysis tool (the TRANAIR code) which is accurate, reliable, economical, and flexible to use. Computational results for many interesting configurations are presented.
Johnson, Forrester T.↗
A probabilistic approach to the dynamic analysis of ducts subjected to multibase harmonic and random excitation
The dynamic behavior of the discharge duct of the high-pressure oxidizer turbopump of a cryogenic rocket motor is investigated analytically. The probabilistic analysis program NESSUS (Numerical Evaluation of Stochastic Structures Under Stress; Cruse et al., 1988) is used to treat the uncertainties due to random and harmonic excitation (e.g., pump noise, pump-induced harmonics, and combustion noise), variations in engine inlet pressure, and changes in system damping. The load modeling procedure, the variation in power-spectral density in different zones of the engine structure, and the dynamic structural-analysis technique are described, and the numerical results of the NESSUS analysis are presented in extensive tables and graphs and discussed in detail.
Debchaudhury, Amit↗
An approximate methods approach to probabilistic structural analysis
A major research and technology program in Probabilistic Structural Analysis Methods (PSAM) is currently being sponsored by the NASA Lewis Research Center with Southwest Research Institute as the prime contractor. This program is motivated by the need to accurately predict structural response in an environment where the loadings, the material properties, and even the structure may be considered random. The heart of PSAM is a software package which combines advanced structural analysis codes with a fast probability integration (FPI) algorithm for the efficient calculation of stochastic structural response. The basic idea of PAAM is simple: make an approximate calculation of system response, including calculation of the associated probabilities, with minimal computation time and cost, based on a simplified representation of the geometry, loads, and material. The deterministic solution resulting should give a reasonable and realistic description of performance-limiting system responses, although some error will be inevitable. If the simple model has correctly captured the basic mechanics of the system, however, including the proper functional dependence of stress, frequency, etc. on design parameters, then the response sensitivities calculated may be of significantly higher accuracy.
Mcclung, R. C.↗