825 research outputs found

    Skylab extravehicular mobility unit thermal simulator

    Get PDF
    The analytical methods, thermal model, and user's instructions for the Skylab Extravehicular Mobility Unit (SEMU) routine are presented. This digital computer program was developed for detailed thermal performance predictions of the SEMU on the NASA-JSC Univac 1108 computer system. It accounts for conductive, convective, and radiant heat transfer as well as fluid flow and special component characterization. The program provides thermal performance predictions for a 967 node thermal model in one thirty-sixth (1/36) of mission time when operated at a calculating interval of three minutes (mission time). The program has the operational flexibility to: (1) accept card or magnetic tape data input for the thermal model describing the SEMU structure, fluid systems, crewman and component performance, (2) accept card and/or magnetic tape input of internally generated heat and heat influx from the space environment, and (3) output tabular or plotted histories of temperature, flow rates, and other parameters describing system operating modes

    Computer program for compressible laminar or turbulent nonsimilar boundary layers

    Get PDF
    Description of computer program for solving two dimensional and axisymmetric forms of compressible boundary layer equations for continuity, mean momentum, and mean total enthalp

    Reduction of Furan and the Preparation of Tetramethylene Derivatives

    Get PDF
    During the study of the nitrogen heterocyclics, a convenient method of preparing δ-chlorovaleronitrile was desired. The synthesis developed involved the procedure of Gilman and Louisinian for decarboxylation of furoic acid. The furan obtained was reduced in the presence of palladous oxide palladium black giving a 95 per cent yield of tetrahydrofuran which was split with hydrogen chloride yielding 55 per cent of the theoretical tetramethylene chlorohydrin. Treatment of the chlorohydrin with phosphorus tribromide gave a 98 per cent yield of tetramethylene chlorobromide which gave a 52 per cent yield of δ-chlorovalero nitrile when reacted with sodium cyanide. The chemicals required and the operations involved lend themselves to the preparation of appreciable quantities

    Unsupervised classification and areal measurement of land and water coastal features on the Texas coast

    Get PDF
    Multispectral scanner (MSS) digital data from ERTS-1 was used to delineate coastal land, vegetative, and water features in two portions of the Texas Coastal Zone. Data (Scene ID's 1037-16244 and 1037-16251) acquired on August 29, 1972, were analyzed on NASA Johnson Space Center systems through the use of two clustering algorithms. Seventeen to 30 spectrally homogeneous classes were so defined. Many classes were identified as being pure features such as water masses, salt marsh, beaches, pine, hardwoods, and exposed soil or construction materials. Most classes were identified to be mixtures of the pure class types. Using an objective technique for measuring the percentage of wetland along salt marsh boundaries, an analysis was made of the accuracy of areal measurement of salt marshes. Accuracies ranged from 89 to 99 percent. Aircraft photography was used as the basis for determining the true areal size of salt marshes in the study sites

    Waxy Corn a New Crop

    Get PDF
    When Japan took the Netherland East Indies, we not only lost our main supply of rubber and tin, but also our tapioca starch

    Alcohol Motor Fuels

    Get PDF
    The proposal to encourage the use of power alcohol made from farm crops grown in the Continental United States, as an aid to agriculture, is not new. Since the last consideration, something more than ten years ago, anhydrous ethyl alcohol has become commercially available. This development makes it feasible to use alcohol-gasoline mixtures. The power alcohol project is thus placed upon a new basis and is worthy of a new consideration

    Comparison of Numerical Schemes for a Realistic Computational Aeroacoustics Benchmark Problem

    Get PDF
    In this work, a nonlinear structured-multiblock CAA solver, the NASA GRC BASS code, will be tested on a realistic CAA benchmark problem. The purpose of this test is to ascertain what effect the high-accuracy solution methods used in CAA have on a realistic test problem, where both the mean flow and the unsteady waves are simultaneously computed on a fully curvilinear grid from a commercial grid generator. The proposed test will compare the solutions obtained using several finite-difference methods on identical grids to determine whether high-accuracy schemes have advantages for this benchmark problem

    The Effect of Steffen Waste on the Fermentation of Pentosans from the Corn Stalk

    Get PDF
    It was found that Steffen waste furnishes a suitable source of nitrogen, salts, and buffers for the growth of Aerobacter pectinovorum on pentosan material prepared from corn-stalks

    The Production of Propionic Acid from Pentoses by Propionibacterium pentosaceum

    Get PDF
    Propionibacterium pentosaceum attacks pentoses (xylose, arabinose) with the production of propionic and acetic acids

    Unsteady Validation of a Mean Flow Boundary Condition for Computational Aeroacoustics

    Get PDF
    In this work, a previously developed mean flow boundary condition will be validated for unsteady flows. The test cases will be several reference benchmark flows consisting of vortical gusts convecting in a uniform mean flow, as well as the more realistic case of a vortical gust impinging on a loaded 2D cascade. The results will verify that the mean flow boundary condition both imposes the desired mean flow as well as having little or no effect on the instantaneous unsteady solution
    corecore