2,739 research outputs found
Lean Aerospace Initiative Research Projects Phase III
Summary of Lean Enterprise Team Projects, Product Development Team Projects, Manufacturing Systems Team Projects, Supplier Networks Team Projects, Organizations and People Team Projects, Acquisition Team Project
Film Cooling in Gas Turbine and Nozzle
A gas turbine is a rotating engine that generates its power through the flow of combustion gases. With either an axial or centrifugal compressor, air from the surrounding environment is drawn into the engine intake, where it is compressed and heated before being sent to combustion chamber. Every gas turbine engine has a nozzle as a standard part. Among its many responsibilities include propelling the engine forward, returning exhaust gases to the free stream, and regulating mass flow through the engine. When the power turbine\u27s exhaust exits, the nozzle is directly in the direction of the fumes. Simply put, nozzles are just tubes that allow hot gases to flow through them; they\u27re not much more complicated than that. The highest point on each of these delas is around 2500 kelvin. This research illustrates the film cooling method for gas turbine and nozzle longevity. For film cooling to work, the temperature of the airfoil and nozzle case must be decreased
Apollo Lunar Surface Experiments Package (ALSEP) two years of lunar science
A non-technical look back at the first two years of ALSEP
Analyzing the discharge regime of a large tropical river through remote sensing, ground-based climatic data, and modeling
This study demonstrates the potential for applying passive microwave satellite sensor data to infer the discharge dynamics of large river systems using the main stem Amazon as a test case. The methodology combines (1) interpolated ground-based meteorological station data, (2) horizontally and vertically polarized temperature differences (HVPTD) from the 37-GHz scanning multichannel microwave radiometer (SMMR) aboard the Nimbus 7 satellite, and (3) a calibrated water balance/water transport model (WBM/WTM). Monthly HVPTD values at 0.25° (latitude by longitude) resolution were resampled spatially and temporally to produce an enhanced HVPTD time series at 0.5° resolution for the period May 1979 through February 1985. Enhanced HVPTD values were regressed against monthly discharge derived from the WBM/WTM for each of 40 grid cells along the main stem over a calibration period from May 1979 to February 1983 to provide a spatially contiguous estimate of time-varying discharge. HVPTD-estimated flows generated for a validation period from March 1983 to February 1985 were found to be in good agreement with both observed arid modeled discharges over a 1400-km section of the main stem Amazon. This span of river is bounded downstream by a region of tidal influence and upstream by low sensor response associated with dense forest canopy. Both the WBM/WTM and HVPTD-derived flow rates reflect the significant impact of the 1982–1983 El Niño-;Southern Oscillation (ENSO) event on water balances within the drainage basin
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