The stability of free-electron lasers against filamentation (open access)

The stability of free-electron lasers against filamentation

In inertial confinement fusion (ICF) experiments, the high electromagnetic fields propagating through a relatively dense plasma can result in a transverse instability, causing the matter and light to form filaments oriented parallel to the light beam. We examine whether a similar instability exists in the electron beam of a free-electron laser, where such an instability could interfere with the transfer of beam kinetic energy into optical wave energy. We heuristically examine the instability in a relativistic beam through which an intense laser beam is propagating. We ignore the FEL effects. We estimate how the altered index of refraction in an FEL affects the dispersion relation. Finally, we estimate the effect that the instability could have on the phase coherence of a particle as it transits an FEL. 10 refs., 2 tabs.
Date: September 15, 1987
Creator: Barnard, J. J.; Scharlemann, E. T. & Yu, S. S.
Object Type: Article
System: The UNT Digital Library
Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system: Phase 2, Final report, May 1, 1983-July 31, 1984 (open access)

Advanced development of a pressurized ash agglomerating fluidized-bed coal gasification system: Phase 2, Final report, May 1, 1983-July 31, 1984

KRW Energy Systems Inc. is engaged in the development of a pressurized, fluidized-bed, gasification process at its Waltz Mill Site in Madison, Pennsylvania. The overall objective of the program is to demonstrate the viability of the KRW process for the environmentally acceptable production of low- and medium-Btu fuel gas from a variety of fossilized, carbonaceous feedstocks for electrical power generation, substitute natural gas, chemical feedstocks, and industrial fuels. This report covers Phase II of the contract period (May 1, 1983 to July 31, 1984) and is a continuation of the work performed in 1983 and reported in the Phase I final report, FE-19122-30. Included is work performed in fiscal 1983 to 1984 on PDU testing, process analysis, cold flow scaleup facility, process and component engineering and design, and laboratory support studies.
Date: September 15, 1987
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Calculation of radial and vertical forces on the CIT 1. 75 m vacuum vessel for several TSC disruption scenarios (open access)

Calculation of radial and vertical forces on the CIT 1. 75 m vacuum vessel for several TSC disruption scenarios

The report consists of viewgraphs. (WRF)
Date: September 15, 1987
Creator: Sayer, R.O.
Object Type: Article
System: The UNT Digital Library
Poloidal magnetics studies on swept divertor and internal coil issues. [Viewgraphs - strike points] (open access)

Poloidal magnetics studies on swept divertor and internal coil issues. [Viewgraphs - strike points]

This paper consists of viewgraphs on swept divertors and internal magnet coils for a Compact Ignition Tokamak design. The author concludes that poloidal field energy and volt-second considerations suggest a swept divertor scenario where the outboard strike point moves from small R to large R, while the inboard strike point moves from small Z to large Z. (LSP)
Date: September 15, 1987
Creator: Strickler, D. J.
Object Type: Article
System: The UNT Digital Library
Alleviation of fuselage form drag using vortex flows: Final report (open access)

Alleviation of fuselage form drag using vortex flows: Final report

The concept of using vortex generators to reduce the fuselage form drag of transport aircraft combines the outflow from the plane of symmetry which is induced by the rotational component of the vortex flow with the energization of the boundary layer to reduce the momentum thickness and to delay or eliminate flow separation. This idea was first advanced by the author in 1981. Under a DOE grant, the concept was validated in wind tunnel tests of approximately 1:17 scale models of fuselages of Boeing 747 and Lockheed C-5 aircraft. The search for the minimum drag involved three vortex generator configurations with three sizes of each in six locations clustered in the aft regions of the fuselages at the beginning of the tail upsweep. The local Reynolds number, which is referred to the length of boundary layer run from the nose, was approximately 10{sup 7} so that a fully developed turbulent boundary layer was present. Vortex generator planforms ranged from swept tapered, through swept straight, to swept reverse tapered wings whose semi-spans ranged from 50% to 125% of the local boundary layer thickness. Pitch angles of the vortex generators were varied by inboard actuators under the control of an external proportional …
Date: September 15, 1987
Creator: Wortman, A.
Object Type: Report
System: The UNT Digital Library