Experimental and theoretical studies conducted in support of the development a high performance, hypersonic/hypervelocity shock tunnel facility (AEDC-VKF Tunnel J) capable providing thermochemical equilibrium nonequilibrium flow conditions at enthalpies are presented. Demonstrated capabilities with without magnetohydrodynamic (MHD) augmentation shown. Increases velocity from 12,000 to 21,000 fps were obteined using an MHD nozzle accelerator seeded potassium carbonate. Good agreemerit is...

Abstract : Some results of a continuing research program to develop capability for testing integrated scramjets are reported. During this program, an double-oblique-shock scramjet model was developed provide test bed supersonic combustion tests and instrumentation development essential analysis results. Results presented in which hydrogen fuel injected into the combustor. Injection fuel, from sonic orifices wall, normal flow did not lead satisfactory data, supposedly because cold boundary...

A propfan gear-system technology development program was undertaken to meet the needs of future geared propulsion systems. The design and initial testing a prototype, 13,000 hp, counterrotating gear system are described. Emphasis placed on utilization modern techniques advanced bearing technologies during phase this program. highly instrumented test conducted verify calculations. new facility is described that allows simulation flight-operat ing conditions.

Abstract : A double-oblique-shock scramjet model has been developed using the AEDC-VKF 16-in. Shock Tunnel I at a free-stream Mach number of 11. The was as test bed for development instrumentation and hydrogen fuel injection techniques supersonic combustion experiments to be conducted 54-in. section in F. Difficulties were encountered, especially entrance combustor because combined action separation interaction second shock from cowl lip. Considerable effort expended before these influences...

Abstract : Some results of a continuing research program to develop capability for testing integrated scramjets are reported. During this program, an double-oblique-shock scramjet model was developed provide test bed supersonic combustion tests and instrumentation development essential analysis results. Results presented in which hydrogen fuel injected into the combustor. Injection fuel, from sonic orifices wall, normal flow did not lead satisfactory data, supposedly because cold boundary...

In this paper we investigate the asymptotic behavior of Riesz $s$-energy first $N$ points a greedy sequence on unit circle, for all values $s$ in range $0\leq s<\infty$ (identifying as usual case $s=0$ with logarithmic energy). context sequences coincide classical Leja constructed using potential. We obtain first-order and second-order results. The key idea is to express terms binary representation $N$. Motivated by our results, pose some conjectures general circle.

A new generation of fuel-efficient turboprop propulsion systems is under consideration now that fuel a significant portion the direct operating cost aircraft. Systems in 5000- to 15,000-hp (3730- 11,185-kW) range use conventional propellers or propfan are being studied. Reduction gearing for this next turboprops interest due requirements cruise speed life, and reliability. Detroit Diesel Allison’s past experience with T56 family reduction gearboxes recounted. Probable discussed since...

Abstract We expand upon work from many hands on the decomposition of nuclear maps. Such maps can be characterised by their ability to approximately written as composition and matrices. Under certain conditions (such quasidiagonality), we find a whose behave nicely, preserving multiplication up an arbitrary degree accuracy being constructed order-zero (as in definition dimension). investigate these relate them W*-analogue.

We expand upon work from many hands on the decomposition of nuclear maps. Such maps can be characterized by their ability to approximately written as composition and matrices. Under certain conditions (such quasidiagonality), we find a whose behave nicely, preserving multiplication up an arbitrary degree accuracy being constructed order zero (as in definition dimension). investigate these relate them W*-analog.

E CONOMIC and strategic incentives to reduce aircraft fuel consumption have prompted significant government industry interest in advanced turboprop for the 1990s. Scale-model wind tunnel testing has shown that large improvements propulsive efficiency are achievable with a propfan at high-speed flight conditions of turbofan-powered aircraft. The design concept Fig. 1 is full-size system test evaluation NASA's Propfan Test Assessment (PTA) research program mid-1987. work described herein...

A propfan gear-system technology development program was undertaken to meet the needs of future geared propulsion systems. The design and initial testing a prototype, 13,000 hp, counterrotating gear system are described. Emphasis placed on utilization modern techniques advanced bearing technologies during phase this program. highly instrumented test conducted verify calculations. new facility is described that allows simulation flight-operat ing conditions.