SEARCH · Engineering Papers

Results for “thermal load”

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.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17

All sources NASA NTRS DOE OSTI

NASA NTRS1972

Apollo experience report: Command and service module environmental control system

A comprehensive review is presented of the design philosophy of the Apollo environmental control system together with the development history of the total system and of selected components within the system. In particular, discussions are presented relative to the development history and to the problems associated with the equipment cooling coldplates, the evaporator and its electronic control system, and the space radiator system used for rejection of the spacecraft thermal loads. Apollo flight experience and operational difficulties associated with the spacecraft water system and the waste management system are discussed in detail to provide definition of the problem and the corrective action taken when applicable.

Samonski, F. H., Jr.↗

NASA NTRS1972

Spin test of turbine rotor

Experimental data are presented for the tangential and radial stresses in the disks of the 36,000 horsepower, 4000 rpm turbine for the M-1 engine oxidizer turbopump. The two-stage Curtis turbine is a special light-weight design utilizing thin conical disks with hollow sheet metal blades attached by electron-beam welding techniques. The turbine was fabricated from Inconel 718, a nickel-chromium alloy. The stresses were obtained by strain-gage measurements using a slip-ring assembly to transmit the electrical signals. Measurements were made at different rotative speeds and different thermal loads. In addition to presenting test data, the report describes test equipment, design of associated hardware, test procedures, instrumentation, and tests for the selection and calibration of strain gages.

Vavra, M. H.↗

NASA NTRS1971

Bioresearch Module Design Definition and Space Shuttle Vehicle Integration Study. Volume 1: Basic Report

Preliminary designs of the Bioexplorer spacecraft, developed in an earlier study program, are analyzed and updated to conform to a new specification which includes use of both the Scout and the space shuttle vehicle for launch. The updated spacecraft is referred to as bioresearch module. It is capable of supporting a variety of small biological experiments in near-earth and highly elliptical earth orbits. The baseline spacecraft design is compatible with the Scout launch vehicle. Inboard profile drawings, weight statements, interface drawings, and spacecraft parts and aerospace ground equipment lists are provided to document the design. The baseline design was analyzed to determine the design and cost impact of a set of optional features. These include reduced experiment power and thermal load, addition of an experiment television monitor, and replacement of VHF with S-band communications. The impact of these options on power required, weight change and cost is defined.

Lang, A. L., Jr.↗

NASA NTRS1971

The NASTRAN computer program for structural analysis.

Discussion of a large NASA-sponsored digital computer program for static and dynamic analysis of structures with linear or nonlinear material properties. The program fits to perform buckling analysis, vibration mode analysis of conservative or damped systems, frequency response analysis, and transient response analysis on the IBM 360, UNIVAC 1108, and CDC 6600 computers. It also provides automatic generation of several types of loads such as gravity loads and thermal strain loads, plots of deformed and nondeformed structures, and the choice of alternate analysis methods such as direct or modal formulations of dynamic problems. The program is intended primarily for large problems involving hundreds of thousands of degrees of freedom. A flexible Executive System is provided to facilitate the addition of new functional capabilities to the program.

Macneal, R. H.↗

NASA NTRS1971

Fabrication and testing of tungsten heat pipes for heat pipe cooled reactors.

The choice of chemically vapor deposited (CVD) tungsten as material for the heat pipes is based on studies reported by Busse et al. (1970). Aspects of pipe construction are discussed together with wick construction, and heat pipe operation. An auxiliary heater was used to overcome problems during the start of operation in the case of a thermally loaded pipe. Two heat pipes were operated at temperatures up to 1850 K. Annular and channeled wicks were investigated. The design of a cross flow heat exchanger is presented together with the design of a reactor heat pipe life test station.

Bacigalupi, R. J.↗

NASA NTRS1972

The role of process history, phase morphology and interface strength upon the mechanical properties of dispersion strengthened alloys

An analytical rationale for the sensitivity-insensitivity of dispersion-strengthened systems to process history is provided. In particular, the research was focussed upon the influence of the particle-matrix interface bond in TD-Nickel and TD-Nichrome, and the manner in which the differences in both elastic constants and thermal expansion coefficients between these phases stress this interface when these alloys are subjected to mechanical and thermal loads upon the mechanical properties of these alloys.

Ansell, G. S.↗

NASA NTRS1973

Design and test of a self-controlled heat pipe radiator.

A 15,000-W spacecraft waste heat rejection system utilizing heat pipe radiator panels has been investigated. Of the several concepts initially identified, a series system was selected for more in-depth analysis. As a demonstration of system feasibility, a nominal 500-W radiator panel has been designed, built, and bench tested. The panel, which is a module of the 15,000-W system, consists of a variable conductance heat pipe (VCHP) header, and six isothermalizer heat pipes attached to a radiator. The thermal load to the VCHP is supplied by a Freon 21 liquid loop via an integral heat exchanger. This paper describes the results of the system studies and the radiator design. Also presented are test data on the VCHP, heat exchanger and isothermalizer heat pipes.

Swerdling, B.↗

NASA NTRS1975

Thermoelastic analysis of solar cell arrays and their material properties

Announced report discusses experimental test program in which five different solar cell array designs were evaluated by subjecting them to 60 thermal cycles from minus 190 deg to 0.0 deg. Results indicate that solder-coated cells combined with Kovar n-interconnectors and p-interconnectors are more durable under thermal loading than other configurations.

Salama, M. A.↗

NASA NTRS1973

Space shuttle atmospheric revitalization subsystem/active thermal control subsystem computer program (users manual)

A shuttle (ARS) atmosphere revitalization subsystem active thermal control subsystem (ATCS) performance routine was developed. This computer program is adapted from the Shuttle EC/LSS Design Computer Program. The program was upgraded in three noteworthy areas: (1) The functional ARS/ATCS schematic has been revised to accurately synthesize the shuttle baseline system definition. (2) The program logic has been improved to provide a more accurate prediction of the integrated ARS/ATCS system performance. Additionally, the logic has been expanded to model all components and thermal loads in the ARS/ATCS system. (3) The program is designed to be used on the NASA JSC crew system division's programmable calculator system. As written the new computer routine has an average running time of five minutes. The use of desk top type calculation equipment, and the rapid response of the program provides the NASA with an analytical tool for trade studies to refine the system definition, and for test support of the RSECS or integrated Shuttle ARS/ATCS test programs.

Source record↗

NASA NTRS1973

Heat pipe radiator

A 15,000 watt spacecraft waste heat rejection system utilizing heat pipe radiator panels was investigated. Of the several concepts initially identified, a series system was selected for more in-depth analysis. As a demonstration of system feasibility, a nominal 500 watt radiator panel was designed, built and tested. The panel, which is a module of the 15,000 watt system, consists of a variable conductance heat pipe (VCHP) header, and six isothermalizer heat pipes attached to a radiating fin. The thermal load to the VCHP is supplied by a Freon-21 liquid loop via an integral heat exchanger. Descriptions of the results of the system studies and details of the radiator design are included along with the test results for both the heat pipe components and the assembled radiator panel. These results support the feasibility of using heat pipes in a spacecraft waste heat rejection system.

Swerdling, B.↗

NASA NTRS1975

Finite-element solution for a combined radiative-conductive analysis with mixed diffuse-specular surface characteristics

The finite-element method has been applied to solve a combined radiative-conductive heat transfer problem for a large space telescope similar to those used in orbiting satellites. The derivation of the underlying matrices and associated solution algorithm for a 2-D triangular element is presented in detail. The resulting expressions for this triangular element typify such an analysis, which yields constitutive matrices when the heat equation is cast in the matrix form. The relevant matrices include those pertaining to thermal conductance, internal heat generation, radiative exchanges, and all possible external thermal loadings. Emphasis is placed on the treatment of non-linear radiative interchange between surfaces in an enclosure having mixed diffuse-specular surface characteristics. Essential differences in governing equations describing these distinctive surface characteristics are identified. Concluding remarks are drawn from an example simulating a Cassegrainian space telescope.

Lee, H.-P.↗

NASA NTRS1975

Solar heating and cooling: Technical data and systems analysis

The solar energy research is reported including climatic data, architectural data, heating and cooling equipment, thermal loads, and economic data. Lists of data sources presented include: selected data sources for solar energy heating and cooling; bibliography of solar energy, and other energy sources; sources for manufacturing and sales, solar energy collectors; and solar energy heating and cooling projects.

Christensen, D. L.↗

NASA NTRS1976

Solar heating and cooling technical data and systems analysis

The accomplishments of a project to study solar heating and air conditioning are outlined. Presentation materials (data packages, slides, charts, and visual aids) were developed. Bibliographies and source materials on materials and coatings, solar water heaters, systems analysis computer models, solar collectors and solar projects were developed. Detailed MIRADS computer formats for primary data parameters were developed and updated. The following data were included: climatic, architectural, topography, heating and cooling equipment, thermal loads, and economics. Data sources in each of these areas were identified as well as solar radiation data stations and instruments.

Christensen, D. L.↗

NASA NTRS1977

Honeycomb chassis for electronic components

In new electronic chassis support, machined honeycomb members are used to change basic relationship between chassis and support structure. Improved chassis combines internal and external support and heat dissipation by altering chassis internal geometry. Honeycomb materials allow mechanical support and thermal load sharing to be combined at lower weight and lower cost than previous equipment.

Read, W. S.↗

NASA NTRS1977

Analysis of shear test method for composite laminates

An elastic plane stress finite element analysis of the stress distributions in four flat test specimens for in-plane shear response of composite materials subjected to mechanical or thermal loads is presented. The shear test specimens investigated include: slotted coupon, cross beam, losipescu, and rail shear. Results are presented in the form of normalized shear contour plots for all three in-plane stess components. It is shown that the cross beam, losipescu, and rail shear specimens have stress distributions which are more than adequate for determining linear shear behavior of composite materials. Laminate properties, core effects, and fixture configurations are among the factors which were found to influence the stress distributions.

Bergner, H. W., Jr.↗

NASA NTRS1977

Nonlinear analysis of bonded joints with thermal effects

Nonlinear results are presented for adhesive bonded joints. It is shown that adhesive nonlinearities are only significant in the predicted adhesive shear stresses. Adherend nonlinearities and temperature dependent properties are shown to have little effect upon the adhesive stress predictions under mechanical and thermal loadings.

Humphreys, E. A.↗

NASA NTRS1977

A shock isolator for diode laser operation on a closed-cycle refrigerator

A device developed to isolate the diode laser from impact shocks delivered during the expansion phase of the Solvay cycle of a helium refrigerator is briefly described. The device uses intermediate cold stations in the stand-off, which permit the stand-off to be short and rigid while minimizing the thermal load at the diode mount.

Jennings, D. F.↗

NASA NTRS1977

Computations in turbulent flows and off-design performance predictions for airframe-integrated scramjets

The research activity focused on two main tasks: (1) the further development of the SCRAM program and, in particular, the addition of a procedure for modeling the mechanism of the internal adjustment process of the flow, in response to the imposed thermal load across the combustor and (2) the development of a numerical code for the computation of the variation of concentrations throughout a turbulent field, where finite-rate reactions occur. The code also includes an estimation of the effect of the phenomenon called 'unmixedness'.

Goglia, G. L.↗