The DIII-D divertor cryopump system: Design and operational experience
Abstract
A high throughput cryocondensation pump has been installed inside the DIII-D plasma chamber as part of the Advanced Divertor Program. During normal plasma discharges the pumping surface temperature must remain sufficiently low (<6.3 K) to pump deuterium while the pump is subjected to transient Joule heating induced by the Ohmic heating coils as well as energetic particles from the plasma. A cryogenic cooling system was specifically designed to handle pulsed heat loads up to 100 W lasting for 10 S. Prototype testing was carried out to verify and develop pulsed capability. During characterization tests, deuterium pumping speeds of 42,000 {ell}/s at 0.66 Pa pressure were achieved. This speed was maintained during 300 W, 8 s long test heat pulses. Physics experiments with the cryopump have been very successful showing a 50% plasma density reduction during H-mode. The design of the advanced divertor cryosystem and cryosystem operational experience are presented.
- Authors:
-
- General Atomics, San Diego, CA (United States); and others
- Publication Date:
- Research Org.:
- General Atomics, San Diego, CA (United States); Oak Ridge National Lab., TN (United States)
- Sponsoring Org.:
- USDOE, Washington, DC (United States)
- OSTI Identifier:
- 10194505
- Report Number(s):
- GA-A-21787; CONF-940843-10
ON: DE95003007; BR: 35AT10020/35AT15040
- DOE Contract Number:
- AC03-89ER51114; AC05-84OR21400
- Resource Type:
- Conference
- Resource Relation:
- Conference: 18. European symposium on fusion technology (SOFT-18),Karlsruhe (Germany),22-26 Aug 1994; Other Information: PBD: Oct 1994
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DIVERTORS; CRYOPUMPS; DESIGN; DOUBLET-3 DEVICE; PERFORMANCE; JOULE HEATING; 700420; 700480; PLASMA-FACING COMPONENTS; COMPONENT DEVELOPMENT; MATERIALS STUDIES
Citation Formats
Schaubel, K M, Smith, J P, and Laughon, G J. The DIII-D divertor cryopump system: Design and operational experience. United States: N. p., 1994.
Web.
Schaubel, K M, Smith, J P, & Laughon, G J. The DIII-D divertor cryopump system: Design and operational experience. United States.
Schaubel, K M, Smith, J P, and Laughon, G J. 1994.
"The DIII-D divertor cryopump system: Design and operational experience". United States.
@article{osti_10194505,
title = {The DIII-D divertor cryopump system: Design and operational experience},
author = {Schaubel, K M and Smith, J P and Laughon, G J},
abstractNote = {A high throughput cryocondensation pump has been installed inside the DIII-D plasma chamber as part of the Advanced Divertor Program. During normal plasma discharges the pumping surface temperature must remain sufficiently low (<6.3 K) to pump deuterium while the pump is subjected to transient Joule heating induced by the Ohmic heating coils as well as energetic particles from the plasma. A cryogenic cooling system was specifically designed to handle pulsed heat loads up to 100 W lasting for 10 S. Prototype testing was carried out to verify and develop pulsed capability. During characterization tests, deuterium pumping speeds of 42,000 {ell}/s at 0.66 Pa pressure were achieved. This speed was maintained during 300 W, 8 s long test heat pulses. Physics experiments with the cryopump have been very successful showing a 50% plasma density reduction during H-mode. The design of the advanced divertor cryosystem and cryosystem operational experience are presented.},
doi = {},
url = {https://www.osti.gov/biblio/10194505},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Oct 01 00:00:00 EDT 1994},
month = {Sat Oct 01 00:00:00 EDT 1994}
}