A rf power system has been developed, which allows the use of rf plasma devices in an electric propulsion test facility without excessive noise pollution in thruster diagnostics. Of particular importance are thrust stand measurements, which were previously impossible due to noise. Three major changes were made to the rf power system: first, the cable connection was changed from a balanced trans...

In this paper, Computational Fluid Dynamics technique and numerical analysis is used to investigate the rocket thrust chamber cooling characteristics. The scope of the investigation involves the study of effect of aspect ratio (height/width) on the heat transfer characteristics of coolant channel. Steady state pressure based analysis of semi cryogenic thrust chamber regenerative cooling channel...

The behavior of small-scale propellers operating in vertical descent and through the vortex ring state (VRS) was measured. In particular, a total of 26 propellers with diameters ranging from 9 to 11 in. (0.229 to 0.279 m) were tested in the University of Illinois at Urbana-Champaign (UIUC) 2.8×4 ft (0.853×1.219 m) low-turbulence wind tunnel at low Reynolds numbers to measure the propeller thrus...

Wind tunnel experiments were performed to investigate the effects of downstream-facing winglets on the wake dynamics, power and thrust of a model wind turbine. Two similar turbines with and without winglets were operated under the same conditions. Results show an increase in the power and thrust coefficients of 8.2% and 15.0% for the wingletted case. A simple theoretical treatment of a two-turb...

This Note proposes a novel radial-thrust combo metal mesh foil bearing (MMFB). Although MMFBs have advantages such as higher stiffness and damping over conventional air foil bearings, studies related to MMFBs have been limited to radial MMFBs. The novel combo MMFB is composed of a radial top foil, thrust top foils, and a ring-shaped metal mesh damper--fabricated by compressing a copper wire mes...

[1] In the Shiquanhe area of far-western Tibet, midCretaceous strata lie unconformable on ophiolitic melange and Jurassic flysch associated with the Bangong-Nujiang suture zone. On the basis of our mapping and geochronologic studies, we suggest that these Cretaceous strata were shortened by >57% over a north south distance of 50 km during Late Cretaceousearly Tertiary time. The Late Cretaceous ...