# Numerical investigation on target implosions driven by radiation ablation and shock compression in dynamic hohlraums

## Abstract

In a dynamic hohlraum driven inertial confinement fusion (ICF) configuration, the target may experience two different kinds of implosions. One is driven by hohlraum radiation ablation, which is approximately symmetric at the equator and poles. The second is caused by the radiating shock produced in Z-pinch dynamic hohlraums, only taking place at the equator. To gain a symmetrical target implosion driven by radiation ablation and avoid asymmetric shock compression is a crucial issue in driving ICF using dynamic hohlraums. It is known that when the target is heated by hohlraum radiation, the ablated plasma will expand outward. The pressure in the shocked converter plasma qualitatively varies linearly with the material temperature. However, the ablation pressure in the ablated plasma varies with 3.5 power of the hohlraum radiation temperature. Therefore, as the hohlraum temperature increases, the ablation pressure will eventually exceed the shock pressure, and the expansion of the ablated plasma will obviously weaken the shock propagation and decrease its velocity after propagating into the ablator plasma. Consequently, longer time duration is provided for the symmetrical target implosion driven by radiation ablation. In this paper these processes are numerically investigated by changing drive currents or varying load parameters. The simulation resultsmore »

- Authors:

- Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)

- Publication Date:

- OSTI Identifier:
- 22410325

- Resource Type:
- Journal Article

- Journal Name:
- Physics of Plasmas

- Additional Journal Information:
- Journal Volume: 22; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1070-664X

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ABLATION; COMPRESSION; IMPLOSIONS; INERTIAL CONFINEMENT; LINEAR Z PINCH DEVICES; NUMERICAL ANALYSIS; PLASMA; PLASMA EXPANSION; PLASMA SIMULATION; SHOCK WAVES; SYMMETRY; TEMPERATURE DEPENDENCE; THERMONUCLEAR FUELS; WAVE PROPAGATION

### Citation Formats

```
Xiao, Delong, Sun, Shunkai, Zhao, Yingkui, Ding, Ning, Wu, Jiming, Dai, Zihuan, Yin, Li, Zhang, Yang, and Xue, Chuang.
```*Numerical investigation on target implosions driven by radiation ablation and shock compression in dynamic hohlraums*. United States: N. p., 2015.
Web. doi:10.1063/1.4921332.

```
Xiao, Delong, Sun, Shunkai, Zhao, Yingkui, Ding, Ning, Wu, Jiming, Dai, Zihuan, Yin, Li, Zhang, Yang, & Xue, Chuang.
```*Numerical investigation on target implosions driven by radiation ablation and shock compression in dynamic hohlraums*. United States. doi:10.1063/1.4921332.

```
Xiao, Delong, Sun, Shunkai, Zhao, Yingkui, Ding, Ning, Wu, Jiming, Dai, Zihuan, Yin, Li, Zhang, Yang, and Xue, Chuang. Fri .
"Numerical investigation on target implosions driven by radiation ablation and shock compression in dynamic hohlraums". United States. doi:10.1063/1.4921332.
```

```
@article{osti_22410325,
```

title = {Numerical investigation on target implosions driven by radiation ablation and shock compression in dynamic hohlraums},

author = {Xiao, Delong and Sun, Shunkai and Zhao, Yingkui and Ding, Ning and Wu, Jiming and Dai, Zihuan and Yin, Li and Zhang, Yang and Xue, Chuang},

abstractNote = {In a dynamic hohlraum driven inertial confinement fusion (ICF) configuration, the target may experience two different kinds of implosions. One is driven by hohlraum radiation ablation, which is approximately symmetric at the equator and poles. The second is caused by the radiating shock produced in Z-pinch dynamic hohlraums, only taking place at the equator. To gain a symmetrical target implosion driven by radiation ablation and avoid asymmetric shock compression is a crucial issue in driving ICF using dynamic hohlraums. It is known that when the target is heated by hohlraum radiation, the ablated plasma will expand outward. The pressure in the shocked converter plasma qualitatively varies linearly with the material temperature. However, the ablation pressure in the ablated plasma varies with 3.5 power of the hohlraum radiation temperature. Therefore, as the hohlraum temperature increases, the ablation pressure will eventually exceed the shock pressure, and the expansion of the ablated plasma will obviously weaken the shock propagation and decrease its velocity after propagating into the ablator plasma. Consequently, longer time duration is provided for the symmetrical target implosion driven by radiation ablation. In this paper these processes are numerically investigated by changing drive currents or varying load parameters. The simulation results show that a critical hohlraum radiation temperature is needed to provide a high enough ablation pressure to decelerate the shock, thus providing long enough time duration for the symmetric fuel compression driven by radiation ablation.},

doi = {10.1063/1.4921332},

journal = {Physics of Plasmas},

issn = {1070-664X},

number = 5,

volume = 22,

place = {United States},

year = {2015},

month = {5}

}