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Computer program integrates path of relativistic electron through region of nonuniform static electromagnetic fields with accuracy of 1 micrometer in 10 centimeters. Program can ue be used to evaluate and modify design of electron-imaging systems. Language is FORTRAN IV, for batch or interactive execution on PDP 10, 11, CYBER 70, 170, and CDC 6000.
Thermal and stress analyses, elastic math models, verification testing, deformation and aeroelastic analyses, and integrated computer programs are addressed.
Guidelines for research on composite materials directed toward the improvement of all aspects of their applicability for general aviation aircraft were developed from extensive studies of their performance, manufacturability, and cost effectiveness. Specific areas for research and for manufacturing development were identified and evaluated. Inputs developed from visits to manufacturers were used in part to guide these evaluations, particularly in the area of cost effectiveness. Throughout the emphasis was to direct the research toward the requirements of general aviation aircraft, for which relatively low load intensities are encountered, economy of production is a prime requirement, and yet performance still commands a premium. A number of implications regarding further directions for developments in composites to meet these requirements also emerged from the studies. Chief among these is the need for an integrated (computer program) aerodynamic/structures approach to aircraft design.
The equations of motion are developed for a perfectly flexible, inelastic tether with a satellite at its extremity. The tether is attached to a space vehicle in orbit. The tether is allowed to possess electrical conductivity. A numerical solution algorithm to provide the motion of the tether and satellite system is presented. The resulting differential equations can be solved by various existing standard numerical integration computer programs. The resulting differential equations allow the introduction of approximations that can lead to analytical, approximate general solutions. The differential equations allow more dynamical insight of the motion.
Some routine supervisory functions performed automatically. Program Management Facility (PMF) computer program integrated software-development and control system. Applicable to large software systems involving as many as several hundred programmers and one million lines of codes, it ensures timely and orderly planning, development, implementation, and documentation of software. Designed as support tool. Has many features providing efficient processing and utilization of space for development programmer. Incorporates security system to prevent improper maintenance. Provides full set of cross-referenced reports and supervisory functions for detailed management information. Written in assembler. IBM program TSO required.
The viewgraphs and discussion on code validation for the simulation of supersonic viscous flow about the F-16XL are provided. Because of the large potential gains related to laminar flow on the swept wings of supersonic aircraft, interest in the applications of laminar flow control (LFC) techniques in the supersonic regime has increased. A supersonic laminar flow control (SLFC) technology program is currently underway within NASA. The objective of this program is to develop the data base and design methods that are critical to the development of laminar flow control technology for application to supersonic transport aircraft design. Towards this end, the program integrates computational investigations underway at NASA Ames-Moffett and NASA Langley with flight-test investigations being conducted on the F-16XL at the NASA Ames-Dryden Research Facility in cooperation with Rockwell International. The computational goal at NASA Ames-Moffett is to integrate a thin-layer Reynolds averaged Navier-Stokes flow solver with a stability analysis code. The flow solver would provide boundary layer profiles to the stability analysis code which in turn would predict transition on the F-16XL wing. To utilize the stability analysis codes, reliable boundary layer data is necessary at off-design cases. Previously, much of the prediction of boundary layer transition has been accomplished through the coupling of boundary layer codes with stability theory. However, boundary layer codes may have difficulties at high Reynolds numbers, of the order of 100 million, and with the current complex geometry in question. Therefore, a reliable code which solves the thin-layer Reynolds averaged Navier-Stokes equations is needed. Two objectives are discussed, the first in greater depth. The first objective is method verification, via comparisons of computations with experiment, of the reliability and robustness of the code. To successfully implement LFC techniques to the F-16XL wing, the flow about the leading edge must be maintained as laminar flow. Therefore, the second objective is to focus on a series of numerical simulations with different values of angle of attack, alpha, and Reynolds numbers. The purpose of the simulations is to study their effects on the two main factors which precipitate transition to turbulence at leading edges of highly swept wings (e.g., 'spanwise contamination' and 'crossflow instability').
Disk Recording System (DRS) is a systems-integration computer program for a direct-to-disk (DTD) high-speed data acquisition system (HDAS) that records rocket-engine test data. The HDAS consists partly of equipment originally designed for recording the data on tapes. The tape recorders were replaced with hard-disk drives, necessitating the development of DRS to provide an operating environment that ties two computers, a set of five DTD recorders, and signal-processing circuits from the original tape-recording version of the HDAS into one working system. DRS includes three subsystems: (1) one that generates a graphical user interface (GUI), on one of the computers, that serves as a main control panel; (2) one that generates a GUI, on the other computer, that serves as a remote control panel; and (3) a data-processing subsystem that performs tasks on the DTD recorders according to instructions sent from the main control panel. The software affords capabilities for dynamic configuration to record single or multiple channels from a remote source, remote starting and stopping of the recorders, indexing to prevent overwriting of data, and production of filtered frequency data from an original time-series data file.
In the software development process, code needs to be tested before it can be packaged for release in order to make sure the program actually does what it says is supposed to happen as well as to check how the program deals with errors and edge cases (such as negative or very large numbers). One of the major parts of the testing process is unit testing, where you test specific units of the code to make sure each individual part of the code works. This project is about unit testing many different components of the ACL software and fixing any errors encountered. To do this, mocks of other objects need to be created and every line of code needs to be exercised to make sure every case is accounted for. Mocks are important to make because it gives direct control of the environment the unit lives in instead of attempting to work with the entire program. This makes it easier to achieve the second goal of exercising every line of code.
A computer code was developed to evaluate the space radiation environment encountered by geocentric satellites. The Short Orbital Flux Integration Program (SOFIP) is a compact routine of modular compositions, designed mostly with structured programming techniques in order to provide core and time economy and ease of use. The program in its simplest form produces for a given input trajectory a composite integral orbital spectrum of either protons or electrons. Additional features are available separately or in combination with the inclusion of the corresponding (optional) modules. The code is described in detail, and the function and usage of the various modules are explained. A program listing and sample outputs are attached.
Computer program for determining radiating nonadiabatic inviscid flow over blunt body by integral equations
Reaction control system integrated systems performance analysis LM computer program - users manual
Computer program for determination of equilibrium air flow field data about blunt bodies by integral relations method
Computer program for simulation of nominal and anomalous operation of Apollo cryogenics storage system
This paper describes the application of a numerical differencing analyzer computer program to the thermal analyzation of a MIUS model. The MIUS model which was evaluated is one which would be required to support a 648-unit Garden Apartment Complex. This computer program was capable of predicting the thermal performance of this MIUS from the impressed electrical, heating, and cooling loads.
A FORTRAN computer program for anisotropic shallow-shell finite elements with variable curvature is described. A listing of the program is presented together with printed output for a sample case. Computation times and central memory requirements are given for several different elements. The program is based on a stiffness (displacement) finite-element model in which the fundamental unknowns consist of both the displacement and the rotation components of the reference surface of the shell. Two triangular and four quadrilateral elements are implemented in the program. The triangular elements have 6 or 10 nodes, and the quadrilateral elements have 4 or 8 nodes. Two of the quadrilateral elements have internal degrees of freedom associated with displacement modes which vanish along the edges of the elements (bubble modes). The triangular elements and the remaining two quadrilateral elements do not have bubble modes. The output from the program consists of arrays corresponding to the stiffness, the geometric stiffness, the consistent mass, and the consistent load matrices for individual elements. The integrals required for the generation of these arrays are evaluated by using symbolic (or analytic) integration in conjunction with certain group-theoretic techniques. The analytic expressions for the integrals are exact and were developed using the symbolic and algebraic manipulation language.
Integration of a supersonic inlet simulation with a computer aided design (CAD) system is demonstrated. The integration is performed using the Project Integration Architecture (PIA). PIA provides a common environment for wrapping many types of applications. Accessing geometry data from CAD files is accomplished by incorporating appropriate function calls from the Computational Analysis Programming Interface (CAPRI). CAPRI is a CAD vendor neutral programming interface that aids in acquiring geometry data directly from CAD files. The benefits of wrapping a supersonic inlet simulation into PIA using CAPRI are; direct access of geometry data, accurate capture of geometry data, automatic conversion of data units, CAD vendor neutral operation, and on-line interactive history capture. This paper describes the PIA and the CAPRI wrapper and details the supersonic inlet simulation demonstration.
Computer program performs the many calculations necessary for solving radiating, nonadiabatic flow of air in chemical equilibrium. Solution method provides accurate description of blunt body flow field in subsonic region.
Computer program for parametric testing saves time and effort in research and development of integrated circuits. Software system automatically assembles various types of test structures and lays them out on silicon chip, generates sequency of test instructions, and interprets test data. Employs self-programming software; needs minimum of human intervention. Adapted to needs of different laboratories and readily accommodates new test structures. Program codes designed to be adaptable to most computers and test equipment now in use. Written in high-level languages to enhance transportability.