Design and analysis of the cryopump for the DIII-D upper divertor

Author

Reis, E.E. ; Baxi, C.B. ; Bozek, A.S.

Author_Institution

Gen. Atomics, San Diego, CA, USA

fYear

1999

fDate

1999

Firstpage

519

Lastpage

522

Abstract

A cryocondensation pump for the upper inboard divertor on DIII-D is to be installed in the vacuum vessel in the fall of 1999. The cryopump removes neutral gas particles from the divertor and prevents recycling to the plasma. This pump is designed for a pumping speed of 18,000 l/s at 0.4 mTorr. The cryopump is toroidally continuous to minimize inductive voltages and avoid electrical breakdown during disruptions. The cryopump consists of a 25 mm Inconel tube cooled by liquid helium and is surrounded by nitrogen cooled shields. A segmented ambient temperature radiation/particle shield protects the nitrogen shields. The pump is subjected to a steady state heat load of less than 10 W due to conduction and radiation heat transfer

Keywords

cryopumping; fusion reactor design; fusion reactor divertors; 0.4 mtorr; 25 mm; DIII-D tokamak; DIII-D upper divertor; He; Inconel tube; cryocondensation pump; cryopump design; disruptions; fusion reactor; inboard divertor; neutral gas particles; shield; vacuum vessel; Breakdown voltage; Electric breakdown; Heat pumps; Heat transfer; Helium; Nitrogen; Plasma temperature; Protection; Recycling; Steady-state;

fLanguage

English

Publisher

ieee

Conference_Titel

Fusion Engineering, 1999. 18th Symposium on

Conference_Location

Albuquerque, NM

Print_ISBN

0-7803-5829-5

Type

conf

DOI

10.1109/FUSION.1999.849892

Filename

849892