20,612 research outputs found
Computational methods in the prediction of advanced subsonic and supersonic propeller induced noise: ASSPIN users' manual
This document describes the computational aspects of propeller noise prediction in the time domain and the use of high speed propeller noise prediction program ASSPIN (Advanced Subsonic and Supersonic Propeller Induced Noise). These formulations are valid in both the near and far fields. Two formulations are utilized by ASSPIN: (1) one is used for subsonic portions of the propeller blade; and (2) the second is used for transonic and supersonic regions on the blade. Switching between the two formulations is done automatically. ASSPIN incorporates advanced blade geometry and surface pressure modelling, adaptive observer time grid strategies, and contains enhanced numerical algorithms that result in reduced computational time. In addition, the ability to treat the nonaxial inflow case has been included
Heat transfer and pressure measurements and comparison with prediction for the SSME two-stage turbine
Time averaged Stanton number and surface pressure distributions are reported for the first stage vane row, the first stage blade row, and the second stage vane row of the Rocketdyne Space Shuttle Main Engine (SSME) two-stage fuel-side turbine. Unsteady pressure envelope measurements for the first blade are also reported. These measurements were made at 10 percent, 50 percent, and 90 percent span on both the pressure and suction surfaces of the first stage components. Additional Stanton number measurements were made on the first stage blade platform, blade tip, and shroud, and at 50 percent span on the second vane. A shock tube was used as a short duration source of heated and pressurized air to which the turbine was subjected. Platinum thin film heat flux gages were used to obtain the heat flux measurements, while miniature silicon diaphragm flush-mounted pressure transducers were used to obtain the pressure measurements. The first stage vane Stanton number distributions are compared with predictions obtained using a version of STAN5 and quasi-3D Navier-Stokes solution. This same quasi-3D N-S code was also used to obtain predictions for the first blade and the second vane
Measurement of NO plus plus e minus dissociative recombination in expanding air flows
Measurement of nitric oxide ion-electron dissociative recombination in expanding air flow
Sources of electron energy in weakly ionized expansions of nitrogen
Sources of electron energy in weakly ionized expansions of nitroge
Continuous measurement of shock velocity using a microwave technique
Microwave technique for continuous measurement of shock wave velocit
Integral-method analysis for a hypersonic viscous shock layer with mass injection
Integral method analysis for hypersonic viscous shock layer with mass injectio
Investigation of the concentration and isotopic composition of inputs and outputs of Pb in waters at an upland catchment in NE Scotland
Inverse opal ceria–zirconia: architectural engineering for heterogeneous catalysis
The application of inverse opal structured materials is extended to the ceria–zirconia (Ce_(0.5)Zr_(0.5)O_2) system and the significance of material architecture on heterogeneous catalysis, specifically, chemical oxidation, is examined
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