73 research outputs found
Periodic report, design of a strut supported turbine vane with a wire-form porous shell
Thermal and structural design analysis of strut supported, porous wall turbine van
Experimental evaluation of low cycle thermal fatigue in a turbine vane fabricated from laminated porous material
Analysis of low cycle thermal fatigue in laminated porous wall turbine vane
Analytical and Experimental Evaluation of the Heat Transfer Distribution over the Surfaces of Turbine Vanes
Three airfoil data sets were selected for use in evaluating currently available analytical models for predicting airfoil surface heat transfer distributions in a 2-D flow field. Two additional airfoils, representative of highly loaded, low solidity airfoils currently being designed, were selected for cascade testing at simulated engine conditions. Some 2-D analytical methods were examined and a version of the STAN5 boundary layer code was chosen for modification. The final form of the method utilized a time dependent, transonic inviscid cascade code coupled to a modified version of the STAN5 boundary layer code featuring zero order turbulence modeling. The boundary layer code is structured to accommodate a full spectrum of empirical correlations addressing the coupled influences of pressure gradient, airfoil curvature, and free-stream turbulence on airfoil surface heat transfer distribution and boundary layer transitional behavior. Comparison of pedictions made with the model to the data base indicates a significant improvement in predictive capability
Concepts for manned lunar habitats
The design philosophy that will guide the design of early lunar habitats will be based on a compromise between the desired capabilities of the base and the economics of its development and implantation. Preferred design will be simple, make use of existing technologies, require the least amount of lunar surface preparation, and minimize crew activity. Three concepts for an initial habitat supporting a crew of four for 28 to 30 days are proposed. Two of these are based on using Space Station Freedom structural elements modified for use in a lunar-gravity environment. A third concept is proposed that is based on an earlier technology based on expandable modules. The expandable modules offer significant advantages in launch mass and packaged volume reductions. It appears feasible to design a transport spacecraft lander that, once landed, can serve as a habitat and a stand-off for supporting a regolith environmental shield. A permanent lunar base habitat supporting a crew of twelve for an indefinite period can be evolved by using multiple initial habitats. There appears to be no compelling need for an entirely different structure of larger volume and increased complexity of implantation
BRYNTRN: A baryon transport model
The development of an interaction data base and a numerical solution to the transport of baryons through an arbitrary shield material based on a straight ahead approximation of the Boltzmann equation are described. The code is most accurate for continuous energy boundary values, but gives reasonable results for discrete spectra at the boundary using even a relatively coarse energy grid (30 points) and large spatial increments (1 cm in H2O). The resulting computer code is self-contained, efficient and ready to use. The code requires only a very small fraction of the computer resources required for Monte Carlo codes
Threshold meson production and cosmic ray transport
An interesting accident of nature is that the peak of the cosmic ray
spectrum, for both protons and heavier nuclei, occurs near the pion production
threshold. The Boltzmann transport equation contains a term which is the cosmic
ray flux multiplied by the cross section. Therefore when considering pion and
kaon production from proton-proton reactions, small cross sections at low
energy can be as important as larger cross sections at higher energy. This is
also true for subthreshold kaon production in nuclear collisions, but not for
subthreshold pion production.Comment: 9 pages, 1 figur
Evaluation of Nuclear Power and Renewable Alternatives as Portrayed in UK Local Press Coverage
Comparative Advantages of School and Workplace Environment in Competence Acquisition: Empirical Evidence from a Survey Among Professional Tertiary Education and Training Students in Switzerland
Some Effects of Variable Surface Temperature on Heat Transfer to a Partially Porous Flat Plate
Discussion: “The Additive Nature of Film Cooling From Rows of Holes” (Muska, J. F., Fish, R. W., Suo, M., 1976, ASME J. Eng. Power, 98, pp. 457–463)
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