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An extensive series of noise measurements, for a variety of geometric and operational parameters, was made on models of upper surface blowing (USB) powered lift systems. The data obtained were analyzed and the effects and trends of parametric variation defined. The behavior and nature of USB noise and the design of USB systems with low noise characteristics is examined.
A model for calculating the expected performance of the Apollo unified S-band (USB) communication system is presented. The general organization of the Apollo USB is described. The mathematical model is reviewed and the computer program for implementation of the calculations is included.
Flow turning parameters, static pressures, surface temperatures, surface fluctuating pressures and acceleration levels were measured in the environment of a full-scale upper surface blowing (USB) propulsive-lift test configuration. The test components included a flightworthy CF6-50D engine, nacelle and USB flap assembly utilized in conjunction with ground verification testing of the USAF YC-14 Advanced Medium STOL Transport propulsion system. Results, based on a preliminary analysis of the data, generally show reasonable agreement with predicted levels based on model data. However, additional detailed analysis is required to confirm the preliminary evaluation, to help delineate certain discrepancies with model data and to establish a basis for future flight test comparisons.
The aerodynamic interaction between the wing and an inviscid upper-surface blowing (USB) thick jet with Mach number nonuniformity is treated within the framework of a linear inviscid subsonic compressible flow theory. A two-vortex-sheet model for the jet surface is used to represent the induced flowfields inside and outside the jet. Comparison of the predicted results with experimental data shows good agreement in lift, induced drag, and pitching moment. It is shown that the thin jet flap theory is inadequate for USB configurations with thick jet.
Flow turning parameters, static pressures, surface temperatures, surface fluctuating pressures and acceleration levels were measured in the environment of a full-scale upper surface blowing (USB) propulsive lift test configuration. The test components included a flightworthy CF6-50D engine, nacelle, and USB flap assembly utilized in conjunction with ground verification testing of the USAF YC-14 Advanced Medium STOL Transport propulsion system. Results, based on a preliminary analysis of the data, generally show reasonable agreement with predicted levels based on model data. However, additional detailed analysis is required to confirm the preliminary evaluation, to help delineate certain discrepancies with model data, and to establish a basis for future flight test comparisons.
Recent investigations of ground effects on aerodynamic characteristics have been stimulated by the interest in powered-lift STOL airplanes. The ground effects on upper-surface-blowing (USB) configurations may involve change in both the circulation forces and the jet reaction forces. In this note, a theoretical method is proposed for predicting these effects. It is shown that the predicted results agree well with available experimental data. In particular, the wing-alone method is shown to be incapable of predicting the ground effects of USB configurations.
A study has been completed of the performance benefits to be derived from applying advanced upper-surface blowing (USB) propulsive-lift technology to the E-2C aircraft. The results of comparing four-engine with two-engine USB configurations are discussed, and engine sizing and aerodynamic/structural considerations pertaining to the E-2C/USB modification are examined. The effects of the modification on performance are described in detail with regard to takeoff distance and landing distance estimation in free-deck operations, operations using catapult and arresting gear, ceiling and radar surveillance missions, and range and endurance capability.
USb is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. U3+ is bonded in a body-centered cubic geometry to eight equivalent Sb3- atoms. All U–Sb bond lengths are 3.23 Å. Sb3- is bonded in a body-centered cubic geometry to eight equivalent U3+ atoms.
USb is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. U3+ is bonded to six equivalent Sb3- atoms to form a mixture of corner and edge-sharing USb6 octahedra. The corner-sharing octahedral tilt angles are 0°. All U–Sb bond lengths are 3.10 Å. Sb3- is bonded to six equivalent U3+ atoms to form a mixture of corner and edge-sharing SbU6 octahedra. The corner-sharing octahedral tilt angles are 0°.
USbS is Matlockite structured and crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. U5+ is bonded in a 5-coordinate geometry to four equivalent Sb3- and five equivalent S2- atoms. All U–Sb bond lengths are 3.29 Å. There are one shorter (2.73 Å) and four longer (2.93 Å) U–S bond lengths. Sb3- is bonded to four equivalent U5+ and four equivalent Sb3- atoms to form distorted SbU4Sb4 hexagonal bipyramids that share corners with four equivalent SbU4Sb4 hexagonal bipyramids, corners with twelve equivalent SU5 square pyramids, edges with four equivalent SbU4Sb4 hexagonal bipyramids, edges with four equivalent SU5 square pyramids, and faces with four equivalent SbU4Sb4 hexagonal bipyramids. All Sb–Sb bond lengths are 2.89 Å. S2- is bonded to five equivalent U5+ atoms to form SU5 square pyramids that share corners with twelve equivalent SbU4Sb4 hexagonal bipyramids, corners with four equivalent SU5 square pyramids, edges with four equivalent SbU4Sb4 hexagonal bipyramids, and edges with eight equivalent SU5 square pyramids.
In this report, we describe a data analysis tool developed for decoding and analyzing vehicle data obtained from a passenger vehicle’s onboard controller area network (CAN) bus. The tool developed in this paper provides a timeseries framework to perform domain-specific analysis at scale when interpreting data from a vehicle or a collection of vehicles in light of how to design intelligent vehicle applications. The tool, called Strym, exploits the CAN bus mechanism of modern vehicles to capture data using commercially available CAN-to-USB hardware Comma.ai Panda devices, managed through open-source software Libpanda. Strym permits the decoding of vendor-specific CAN messages in a vehicle-agnostic manner. Through this, a researcher can characterize data throughput, assess data quality, and perform analyses. Such analyses are useful in a number of research such as studying human driving behavior in mixed-autonomy, new driver models, rare-event detection, traffic flow estimation, and custom control of vehicles.
A formulation predicts the variation of circulation forces and jet reaction forces in ground proximity as a function of ground height. The predicted results agree well with available experimental data. It is shown that the wing-alone theory is not capable of predicting the ground effect for USB configurations.
Universal serial bus power delivery (USB-PD) chargers are more attractive to consumers with multiple output ports. Existing multiple port charger designs take multi-stage approach thus increase power loss and charger size. Also, ports are normally designed with different power capability thus the high-power port becomes under-used if the connected device is fully charged while the other lower power ports cannot take over the unused power. This is mainly limited by the power architecture design. This paper addresses this issue by presenting a multiplexing based multi-port quasi-resonant flyback converter. The design achieves true power-sharing with high efficiency, small size, and simple analog implementation. This paper discusses the operating principle and design considerations. A GaN-based 60 W dual port charger verifies the proposed scheme while achieving 76% size reduction and 1% efficiency improvement than state-of-the-art.
Apollo project - phase modulation carrier spectrum analysis
Design consideration of unified S-band antenna on land and shipboard for Apollo project
Computer processing of unified S-band system data from Apollo orbit
Noise characteristics of unified S-band tracking system high speed range rate and X-Y ANGULAR data obtained during aircraft flyby tests