135 research outputs found

    Simulation of powered-lift flows

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    The primary objective is to expose government, industry, and academic scientists to work underway at NASA-Ames towards the application of CFD to the powered lift area. One goal is to produce the technologies which will be required in the application of numerical techniques to, for example, the Supersonic STOVL program. The progress to date on the following specific projects is presented: Jet in ground effect with crossflow; Jet in a crossflow; Delta planform with multiple jets in ground effect; Integration of CFD with thermal and acoustic analyses; Improved flow visualization techniques for unsteady flows; YAV-8B Harrier simulation program; and E-7 simulation program

    Navier-Stokes Analysis of a High Wing Transport High-Lift Configuration with Externally Blown Flaps

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    Insights and lessons learned from the aerodynamic analysis of the High Wing Transport (HWT) high-lift configuration are presented. Three-dimensional Navier-Stokes CFD simulations using the OVERFLOW flow solver are compared with high Reynolds test data obtained in the NASA Ames 12 Foot Pressure Wind Tunnel (PWT) facility. Computational analysis of the baseline HWT high-lift configuration with and without Externally Blown Flap (EBF) jet effects is highlighted. Several additional aerodynamic investigations, such as nacelle strake effectiveness and wake vortex studies, are presented. Technical capabilities and shortcomings of the computational method are discussed and summarized

    Arbetsterapeutisk dokumentation inom socialpsykiatri Tre arbetsterapeuters upplevelser av att dokumentera och faktorer som påverkar deras dokumentation.

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    Att dokumentera är för arbetsterapeuter ett professionellt ansvar och en yrkesskyldighet som regleras av såväl lagar och etik, som interna professionella krav. Den arbetsterapeutiska dokumentationen är viktigt för att förklara arbetsterapi, stödja den arbetsterapeutiska behandlingen, kvalitetssäkring, forskning och samverkan. Tidigare studier har visat på bristfällig dokumentation, speciellt inom socialpsykiatrin, samt att dokumentation kan upplevas som problematisk. Syftet med denna studie var att genom en fokusgruppintervju undersöka hur arbetsterapeuter verksamma inom socialpsykiatri upplever dokumentationen, samt vilka faktorer som påverka densamma. Tre arbetsterapeuter deltog i studien. Resultatet påvisar att tid, etik, lagar och förhållanden på arbetsplatsen upplevdes såväl hindrande som stödjande för dokumentationen. Även journalsystemets utseende samt arbetsterapeutens utbildning och egna inställning tycktes påverka upplevelsen av dokumentation

    High-Lift Optimization Design Using Neural Networks on a Multi-Element Airfoil

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    The high-lift performance of a multi-element airfoil was optimized by using neural-net predictions that were trained using a computational data set. The numerical data was generated using a two-dimensional, incompressible, Navier-Stokes algorithm with the Spalart-Allmaras turbulence model. Because it is difficult to predict maximum lift for high-lift systems, an empirically-based maximum lift criteria was used in this study to determine both the maximum lift and the angle at which it occurs. Multiple input, single output networks were trained using the NASA Ames variation of the Levenberg-Marquardt algorithm for each of the aerodynamic coefficients (lift, drag, and moment). The artificial neural networks were integrated with a gradient-based optimizer. Using independent numerical simulations and experimental data for this high-lift configuration, it was shown that this design process successfully optimized flap deflection, gap, overlap, and angle of attack to maximize lift. Once the neural networks were trained and integrated with the optimizer, minimal additional computer resources were required to perform optimization runs with different initial conditions and parameters. Applying the neural networks within the high-lift rigging optimization process reduced the amount of computational time and resources by 83% compared with traditional gradient-based optimization procedures for multiple optimization runs
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