Simulation Research on Laser Fusion at IAPCM

1. APFA2009 APPTC2009 Oct. 27 - 30, 2009 Aomori, Japan Simulation Research on Laser Fusion at IAPCM Wenbing Pei and Shao-ping Zhu Institute of Applied Physics and Computational Mathematics

2. Introduction • Laser fusion is another way to the fusion energy. • The largest laser facility, NIF, has been completely constructed in US. • The first ignition attempt will start in 2010. direct drive indirect drive

3. Laser fusion research in China • The Concept of laser fusion was independently presented by Prof. Ganchang Wang (王淦昌) in1964. • Laser fusion research in China, started late in 1970s, is now organized by National High-Tech Inertial Confinement Fusion Committee. • Theory and simulation research on Laser Fusion is one of important parts, and mainly carried out in my institute, IAPCM.

4. Outline 1 Overview of our simulation 2 Design and analysis of opacity experiment on SG-II as an example of application 3 Development of new generation of high-performance codes

5. Part 1Overview of our simulation for laser fusion

6. Development of 2D and 3D codes • Many years of effort has been paid to develop 2D and 3D simulation codes for laser fusion, including LARED code series RT3D, a 3D MC radiation transport code without hydro

7. Laser LARED-P LPI LARED-H / RDMG X-ray power albedo RT3D Diagnostic information Radiation drive condition LARED-R / RDMG LARED-I / RDMG LARED-S RDMG Capsule implosion Hydro instability Ablation, Opacity, EOS, etc Radiation transport Key processes of indirect driven laser fusion can be simulated RDMG is a 1Dnon-LTE radiation hydrodynamics code.

8. Laser LARED-P LARED-H / RDMG X-ray power albedo RT3D Diagnostic information Radiation drive condition LARED-R / RDMG LARED-I / RDMG LARED-S RDMG Capsule implosion Hydro instability Ablation, Opacity, EOS, etc Radiation transport

9. Part 2Design and analysisof the high-temperature opacity experiment Collaborator: Research Center of Laser Fusion (LFRC) Yan Xu, et al., Phys. Plasmas 14, 052701 (2007)

10. CH foam: 40mg/cc High-temperature opacity experimentdesign and analysis • Opacity is the important property of a high temperature plasma. • Opacity measurement requires to create uniform LTE plasam state in the clean environment. • In our design, CH foam is used, which prevents reflected laser and hot high-Z plasma from going into the sample region, but allow x rays to pass through and heat the sample. • Our simulation predicted that the sample would be heated near 100eV on SG-II.

11. Experiment results • The experiments were carried out by Research Center of Laser Fusion (LFRC). • The clear Al emission spectrum without backlight shows that a clean environment for measurement is achieved. Al emission spectrum without backlight Al absorption spectrum changes with time.

12. Experiment analysis by Jiyan Zhang, LFRC The sample state is inferred by fitting the experimental spectrum. The temperature and density are 95eV and 25mg/cc, respectively.

13. Simulation of the experiment • The experiment is simulated by three codes in four steps.

14. Part 3Development of new generation of high-performance codes LARED integration LARED-S other codes JAdapative Structured Meshapplications Infrastructure(JASMIN)

15. LARED-H integrate LARED integration LARED-R LARED-I New generation of simulation codes In order to meet the requirement for large-scale simulation of laser fusion research, we are developing new generation of high-performance parallel codes. • 2D code for the Integrated simulation of indirect driven laser fusion • 3D simulation codes for the key processes, such as • Capsule implosion • Laser-plasma interaction

16. ApplicationCode Application modules Code-supporting infrastructure Solution to LARED integration • Solution to develop the LARED integration is based on an object-oriented parallel code-supporting infrastructure, and upon the infrastructure are application modules. • The infrastructure includes • the common components independent of problem and algorithms • the mature and standard algorithm modules • According to our existing codes, the infrastructure focuses on the structured-mesh codes.

17. A parallel software infrastructureJASMIN(JAdaptive Structured Mesh applications INfrastructure) Supports the large scale parallel simulations on adaptive structured mesh (SAMR) using massively parallel processing machines (MPP).http:://www.iapcm.ac.cn/jasmin

18. Structure of new generation of simulation codes for laser fusion Parallel computer system Large scale simulation Paralleled & distributed visualization system JaVis（TB scale）

19. Status • Now, JASMIN have been developed to version 1.8, providing non-structured multi-block mesh and supporting SN methods in radiation transport calculation. • It essentially meets requirement for laser fusion codes. • The codes based on JASMIN are of functions of parallelization and AMR, automatically. • Five codes have been rewritten based on JASMIN. • LARED-H : ALE code for hohlraum physics • LARED-R : Radiation transport Lagrangian code • LARED-S : Euler (AMR) code • LARED-P : PIC code • RT3D : 3D code for radiation transport

20. LARED-H: full simulation of NIF ignition target • Difficulty to simulate indirect-drive laser fusion • Complicated geometry • Multi-material • Large deformation • In order to overtake the difficulty, LARED-H benefiting from JASMIN has been developed largely as follows • Using non-structured multi-block mesh for complicated geometry • Allowing Lagrangian mesh across material interface to deal with large deformation Mix region Initail meshes Remapping with mixed Lagrangian mesh Large deformation

21. LARED-H: full simulation of NIF ignition target S. W. Hann, et al., Phys. Plasmas 2, 2480 (1995) Radiation temperature

22. LARED-S: capsule implosion simulation Capsule: CH, Al, CH V0(107cm/s): 0, -1.5, -1.5 Density AMR: 3 levels 4×4 Level 0: 256×256 Resolution 4096×4096 CH Al CH Material region Level region

23. Laser propagation in a plasma • A 3D fluid code LAP3D for laser propagation is developed on JASMIN. The filamentation can be simulated.

24. Plan in next step • LARED integration code is for the integrated simulation of indirect driven laser fusion. • RT3D, as a postprocessor of LARED integration, is for drive asymmetry analysis on capsule. • LARED-S is for 3D simulation of capsule. • LAP3D, the 3D fluid code, is for simulation of filamentation, SBS and SRS instability in the laser propagation in hohlraum. • All of the codes are developed on JASMIN.

25. Summary • Key processes of indirect driven laser fusion can be simulated by using LARED codes, which have taken an important role in our research on laser fusion. • In order to realize the integrated simulation of laser fusion, we are developing the new generation of high-performance codes based on JASMIN infrastructure.

26. Acknowledgement • Thank the collaborators • My colleagues in Theory Center for Laser Fusion and Computer Center, IAPCM • My colleagues in Research Center of Laser Fusion (LFRC) • Thank Core-University-Program for supporting me to attend APFA2009/APPTC2009.