42,073 research outputs found
Data management study. Appendix P - Contractor data requirements related project interfaces /RP/ Final report
Technical, administrative, and managerial data documentation by contractors on interfaces between Voyager project and related space program
Investigation of light source and scattering medium related to vapor-screen flow visualization in a supersonic wind tunnel
Methods for increasing the radiant in light sheets used for vapor screen set-ups were investigated. Both high-pressure mercury arc lamps and lasers were considered. Pulsed operation of the air-cooled 1-kW lamps increased the light output but decreased reliability. An ellipsoidal mirror improved the output of the air-cooled lamps by concentrating the light but increased the complexity of the housing. Water-cooled-4-kW lamps coupled with high-aperture Fresnel lenses provided reasonable improvements over the air-cooled lamps. Fanned laser beams measurements of scattered light versus dew point made in conjunction with successful attempts to control the fluid injection. A number of smoke generators are described and test results comparing smoke and vapor screens are shown. Finally, one test included a periscope system to relay the image to a camera outside the flow
Charge Transport Scalings in Turbulent Electroconvection
We describe a local-power law scaling theory for the mean dimensionless
electric current in turbulent electroconvection. The experimental system
consists of a weakly conducting, submicron thick liquid crystal film supported
in the annulus between concentric circular electrodes. It is driven into
electroconvection by an applied voltage between its inner and outer edges. At
sufficiently large voltage differences, the flow is unsteady and electric
charge is turbulently transported between the electrodes. Our theoretical
development, which closely parallels the Grossmann-Lohse model for turbulent
thermal convection, predicts the local-power law . and are dimensionless
numbers that are similar to the Rayleigh and Prandtl numbers of thermal
convection, respectively. The dimensionless function , which is
specified by the model, describes the dependence of on the aspect ratio
. We find that measurements of are consistent with the theoretical
model.Comment: 12 pages, 7 figures, Submitted to Phys. Rev. E. See also
http://www.physics.utoronto.ca/nonlinea
Investigation of conventional and Super-X divertor configurations of MAST Upgrade using SOLPS
One of the first studies of MAST Upgrade divertor configurations with
SOLPS5.0 are presented. We focus on understanding main prospects associated
with the novel geometry of the Super-X divertor (SXD). This includes a
discussion of the effect of magnetic flux expansion and volumetric power losses
on the reduction of target power loads, the effect of divertor geometry on the
divertor closure and distribution of neutral species and radiation in the
divertor, the role of the connection length in broadening the target wetted
area. A comparison in conditions typical for MAST inter-ELM H-mode plasmas
confirms improved performance of the Super-X topology resulting in
significantly better divertor closure with respect to neutrals (the atomic flux
from the target increased by a factor of 6, but the atomic flux from the
divertor to the upper SOL reduced by a factor of 2), increased radiation volume
and increased total power loss (a factor of 2) and a reduction of target power
loads through both magnetic flux expansion and larger volumetric power loss in
the divertor (a factor of 5-10 in attached plasmas). The reduction of the
target power load by SXD further increases with collisionality (high density or
detached regimes) thanks to larger importance of volumetric power losses. It is
found that a cold divertor plasma leads to stronger parallel temperature
gradients in the SOL which drive more parallel heat flux, meaning that the
effectiveness of perpendicular transport in spreading the power at the target
can be reduced, and this needs to be taken into account in any optimisation.Comment: 32 pages, 23 figures. This is an author-created, un-copyedited
version of an article accepted for publication in PPCF. IOP Publishing Ltd
and IAEA are not responsible for any errors or omissions in this version of
the manuscript or any version derived from i
Computer program to generate attitude error equations for a gimballed platform
Computer program for solving attitude error equations related to gimballed platform is described. Program generates matrix elements of attitude error equations when initial matrices and trigonometric identities have been defined. Program is written for IBM 360 computer
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