Review of Propulsion Technologies for N+3 Subsonic Vehicle Concepts
Scott W. Ashcraft, Andrés S. Padrón, Kyle A. Pascioni, and Gary W. Stout, Jr. (NASA Aeronautics Academy 2011); Dennis L. Huff (Deputy Chief, Aeropropulsion Division, NASA Glenn Research Center)
NASA has set aggressive fuel burn, noise, and emission reduction goals for a new generation (N+3) of aircraft targeting concepts that could be viable in the 2035 timeframe. Several N+3 concepts have been formulated, where the term “N+3” indicate aircraft three generations later than current state-of-the-art aircraft, “N”. Dramatic improvements need to be made in the airframe, propulsion systems, mission design, and the air transportation system in order to meet these N+3 goals. The propulsion system is a key element to achieving these goals due to its major role with reducing emissions, fuel burn, and noise. This report provides an in-depth description and assessment of propulsion systems and technologies considered in the N+3 subsonic vehicle concepts. Recommendations for technologies that merit further research and development are presented based upon their impact of the N+3 goals and likelihood of being operational by 2035.
Integrated Intermodal Passenger Transportation System
Ryan Klock, David Owens, and Henry Schwartz (NASA Aeronautics Academy 2011); and Robert Plencner (Chief, Multidisciplinary Design Analysis and Optimization Branch, NASA Glenn Research Center)
Modern transportation consists of many unique modes of travel. Each of these modes and their respective industries has evolved independently over time, forming a largely incoherent and inefficient overall transportation system. Travelers today are forced to spend unnecessary time and efforts planning a trip through varying modes of travel each with their own scheduling, pricing, and services; causing many travelers to simply rely on their relatively inefficient and expensive personal automobile. This paper presents a demonstration program system to not only collect and format many different sources of trip planning information, but also combine these independent modes of travel in order to form optimal routes and itineraries of travel. The results of this system show a mean decrease in inter-city travel time of 10% and a 25% reduction in carbon dioxide emissions over personal automobiles. Additionally, a 55% reduction in carbon dioxide emissions is observed for intra-city travel. A conclusion is that current resources are available, if somewhat hidden, to drastically improve point to point transportation in terms of time spent traveling, the cost of travel, and the ecological impact of a trip. Finally, future concepts are considered which could dramatically improve the interoperability and efficiency of the transportation infrastructure.
Enhancement of Aviation Fuel Thermal Stability Characterization through Application of Ellipsometry
Samuel Tucker Browne, Hubert Wong, and Cameron Branch Hinderer (NASA Aeronautics Academy 2011), Jennifer Klettlinger (Research Chemical Engineer, Combustion Branch, NASA Glenn Research Center)
ASTM D3241/Jet Fuel Thermal Oxidation Tester (JFTOT) procedure, the standard method for testing thermal stability of conventional aviation turbine fuels is inherently limited due to the subjectivity in the color standard for tube deposit rating. Quantitative assessment of the physical characteristics of oxidative fuel deposits provides a more powerful method for comparing the thermal oxidation stability characteristics of fuels, especially in a research setting. We propose employing a Spectroscopic Ellipsometer to determine the film thickness and profile of oxidative fuel deposits on JFTOT heater tubes. Using JP-8 aviation fuel and following a modified ASTM D3241 testing procedure, the capabilities of the Ellipsometer will be demonstrated by measuring oxidative fuel deposit profiles for a range of different deposit characteristics.