Variable-cycle engines for supersonic cruise aircraft

Progress and the current status of the Variable Cycle Engine (VCE) study are reviewed with emphasis placed on the impact of technology advancements and design specifications. A large variety of VCE concepts are also examined

Development potential of Intermittent Combustion (I.C.) aircraft engines for commuter transport applications

An update on general aviation (g/a) and commuter aircraft propulsion research effort is reviewed. The following topics are discussed: on several advanced intermittent combustion engines emphasizing lightweight diesels and rotary stratified charge engines. The current state-of-the-art is evaluated for lightweight, aircraft suitable versions of each engine. This information is used to project the engine characteristics that can be expected on near-term and long-term time horizons. The key enabling technology requirements are identified for each engine on the long-term time horizon

Antisoiling technology: Theories of surface soiling and performance of antisoiling surface coatings

Physical examination of surfaces undergoing natural outdoor soiling suggests that soil matter accumulates in up to three distinct layers. The first layer involves strong chemical attachment or strong chemisorption of soil matter on the primary surface. The second layer is physical, consisting of a highly organized arrangement of soil creating a gradation in surface energy from a high associated with the energetic first layer to the lowest possible state on the outer surfce of the second layer. The lowest possible energy state is dictated by the physical nature of the regional atmospheric soiling materials. These first two layers are resistant to removal by rain. The third layer constitutes a settling of loose soil matter, accumulating in dry periods and being removed during rainy periods. Theories and evidence suggest that surfaces that should be naturally resistant to the formation of the first two-resistant layers should be hard, smooth, hydrophobic, free of first-period elements, and have the lowest possible surface energy. These characteristics, evolving as requirements for low-soiling surfaces, suggest that surfaces or surface coatings should be of fluorocarbon chemistry. Evidence for the three-soil-layer concept, and data on the positive performance of candidate fluorocarbon coatings on glass and transparent plastic films after 28 months of outdoor exposure, are presented

THE PRODUCTIVITY AND ALLOCATION OF RESEARCH: U.S. AGRICULTURAL EXPERIMENT STATIONS

The main purpose of this paper is to present estimates of the marginal products and rates of return to the four major categories of agricultural research conducted by U.S. agricultural experiment stations (cash grains, poultry, dairy, and livestock).Productivity Analysis, Research and Development/Tech Change/Emerging Technologies,

GENDER'S ROLE IN MANUSCRIPT ACCEPTANCE: SEX IN THE JOURNAL

Women authors fare poorly at the hands of referees in some economics journals, especially when the review process is not blind. Using data on the 155 manuscripts submitted to the NJARE for publication during the period 1984-88, we found no evidence of differential referee acceptance rates for manuscripts with female and male lead authors.Teaching/Communication/Extension/Profession,

General aviation energy-conservation research programs at NASA-Lewis Research Center

The major thrust of NASA's nonturbine general aviation engine programs is directed toward (1) reduced specific fuel consumption, (2) improved fuel tolerance; and (3) emission reduction. Current and planned future programs in such areas as lean operation, improved fuel management, advanced cooling techniques and advanced engine concepts, are described. These are expected to lay the technology base, by the mid to latter 1980's, for engines whose total fuel costs are as much as 30% lower than today's conventional engines