Introduction to the physics of ICF capsules

Conference · Mon Mar 13 00:00:00 EST 1989

OSTI ID:6038759

Lindl, J D

Inertial Confinement Fusion is an approach to fusion which relies on the inertia of the fuel mass to provide confinement. To achieve conditions under which this confinement is sufficient for efficient thermonuclear burn, high gain ICF targets designed to be imploded directly by laser light. These capsules are generally a spherical shell which is filled with low density DT gas. The shell is composed of an outer region which forms the ablator and an inner region of frozen or liquid DT which forms the main fuel. Energy from the driver is delivered to the ablator which heats up and expands. As the ablator expands and blows outward, the rest of the shell is forced inward to conserve momentum. In this implosion process, several features are important. We define the in-flight-aspect-ratio (IFAR) as the ratio of the shell radius R as it implodes to its thickness {Delta}R. Hydrodynamic instabilities during the implosion impose limits on this ratio which results in a minimum pressure requirement of about 100 Mbar. The convergence ratio is defined as the ratio of the initial outer radius of the ablator to the final compressed radius of the hot spot. This hot spot is the central region of the compressed fuel which is required to ignite the main fuel in high gain designs. Typical convergence ratios are 30--40. To maintain a nearly spherical shape during the implosion, when convergence ratios are this large, the flux delivered to the capsule must be uniform to a few percent. The remainder of this paper discusses the conditions necessary to achieve thermonuclear ignition in these ICF capsules.

• Research Organization: Lawrence Livermore National Lab., CA (USA)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (USA)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6038759
• Report Number(s): UCRL-JC-106493; CONF-880928-6; ON: DE91011207
• Resource Relation: Conference: Course and workshop on inertial confinement fusion, Varenna (Italy), 6-16 Sep 1988
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
LASER TARGETS
THERMONUCLEAR IGNITION
ABLATION
CONVERGENCE
ENERGY LOSSES
INERTIAL CONFINEMENT
LASER FUSION REACTORS
LASER IMPLOSIONS
PLASMA INSTABILITY
X RADIATION
CONFINEMENT
ELECTROMAGNETIC RADIATION
IMPLOSIONS
INSTABILITY
IONIZING RADIATIONS
LOSSES
PLASMA CONFINEMENT
RADIATIONS
TARGETS
THERMONUCLEAR REACTORS
700208* - Fusion Power Plant Technology- Inertial Confinement Technology