Engineering Papers⌕ Search

Engineering topics

Sattarov, Akhdiyor

Publications and source records attributed to Sattarov, Akhdiyor.

Development of Multi-Filament Textured-Powder Bi-2212/Ag Wire With Enhanced Local Area Ratio

The performance and cost of Bi-2212/Ag wire is limited by the large fraction of Ag matrix (~3:1) that is required in the oxide-powder-in-tube fabrication process. An alternative fabrication process is being developed in which fine-powder Bi-2212 is uniaxially compressed to form bars with a thin Ag foil sheath. The fine powder naturally textures (aligns the a-b planes perpendicular to the direction of compaction) with texture >80% using 200 MPa compression. A billet is formed by stacking trapezoidal- cross-section bars in a symmetric 8-12-16 pattern around an Ag rod and enclosed in an Ag-wall extrusion can. Here, the billet is extruded and drawn to fine wire. Results are presented on present status of the development and testing.

17 WIND ENERGY↗

SuperCIC: Enhanced Winding Current Density for Hybrid Windings of Tokamaks

The design is presented for a new approach to cable-in-conduit (SuperCIC) for use in the high-field windings of tokamaks. Two layers of high-field superconductor wires are cabled onto a thin-wall perforated center tube. An overwrap is applied and the cable is inserted as a loose fit into a sheath tube. The sheath tube is drawn down onto the cable to compress the wires onto the center tube and immobilize them. The SuperCIC is then co-wound with a high-strength armor extrusion, which is kerf-cut so that the co-winding onto a coil mandrel can be made without deformation within the armor or the CIC. SuperCIC facilitates hybrid windings, in which subwindings of NbTi are used where B < 7 T, Nb 3 Sn where B < 14 T, and Bi-2212where B > 14 T to minimize superconductor cost. Demount-able splices are used to interconnect layers. A conceptual design has been prepared for a tokamak with aspect ratio A ~ 2.0, magnetic field of 17.4Tat the inner windings and 6.7 T at the plasma,and winding current density ~140 A/mm 2 -sufficient for optimizing the fusion power density in a compact spherical tokamak.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Micro-aligned 1 Tesla Solenoid for High-energy Bunched-beam Electron Cooling

Electron cooling of ion beams requires precise alignment of the electron beam with the equilibrium trajectory of the ion bunch. In magnetized cooling the cooling rate is enhanced by transverse confinement of each electron on a magnetic line of force. The magnetic lines of force must therefore be aligned with the ion bunch trajectory everywhere along the extent of the solenoid. For the parameters required for JLEIC, a solenoid with bore field ~1 T, length ~30 m, and rms alignment of ~micro-radian is required. Such alignment has never been accomplished. The design of a micro-aligned solenoid is presented. A gap-separated stack of thin steel washers is located along the bore of the solenoid. The flux plate stack shields transverse magnetic fields from the interior, so that axial alignment is enhanced by a factor of ~10.

43 PARTICLE ACCELERATORS↗

Status of the MEIC ion collider ring design

We present an update on the design of the ion collider ring of the Medium-energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab. The design is based on the use of super-ferric magnets. It provides the necessary momentum range of 8 to 100 GeV/c for protons and ions, matches the electron collider ring design using PEP-II components, fits readily on the JLab site, offers a straightforward path for a future full-energy upgrade by replacing the magnets with higher-field ones in the same tunnel, and is more cost effective than using presently available current-dominated super-conducting magnets. We describe complete ion collider optics including an independently-designed modular detector region.

43 PARTICLE ACCELERATORS↗

Accelerator driven sub-critical core

Systems and methods for operating an accelerator driven sub-critical core. In one embodiment, a fission power generator includes a sub-critical core and a plurality of proton beam generators. Each of the proton beam generators is configured to concurrently provide a proton beam into a different area of the sub-critical core. Each proton beam scatters neutrons within the sub-critical core. The plurality of proton beam generators provides aggregate power to the sub-critical core, via the proton beams, to scatter neutrons sufficient to initiate fission in the sub-critical core.

43 PARTICLE ACCELERATORS↗