IFE liquid wall response to the prompt X-ray energy deposition: Investigation of physical processes and assessment of ablated material

Mofreh R. Zaghloul, A. René Raffray

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)

Abstract

This paper considers the physical processes and material removal mechanisms associated with the energy deposition in an inertial fusion energy liquid wall from the prompt X-ray spectrum of an indirect-drive inertial fusion target. These are important as the ablated material could generate aerosol in the chamber, which without adequate chamber clearing could result in a chamber environment unsuitable for driver propagation and/or target injection. Simple computations were used to identify and characterize the important material removal mechanisms relevant to the energy deposition regime under consideration. Explosive boiling was found to be the most relevant thermal response mechanism due to the high heating rate from the X-ray photon energy deposition. Investigation showed that explosive boiling occurs when the material temperature approaches the critical temperature and has a threshold value that can be derived from the material equation of state or the rate of homogeneous nucleation. Another important mechanism is mechanical spall that can result when shock wave-induced local tensile stresses exceed the spall strength of the material. Both explosive boiling and mechanical spall occur upon crossing the thermodynamic stability border (spinodal curve) either through rapid heating or through overexpansion of the material. Relevant material properties of the candidate liquid wall materials needed to perform the present assessment are compiled, derived, and presented. A simple energy deposition volumetric analysis is used to estimate both thermally ablated and mechanically spoiled regions of the liquid wall material. The choice of liquid/wall combination is found to play an important role in reducing or eliminating the occurrence of spall in the liquid wall.

Original languageEnglish
Pages (from-to)27-45
Number of pages19
JournalFusion Science and Technology
Volume47
Issue number1
DOIs
Publication statusPublished - Jan 2005

Keywords

  • IFE liquid wall fragmentation
  • Spinodal decomposition and mechanical spall
  • X-ray ablation

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Nuclear and High Energy Physics
  • Nuclear Energy and Engineering
  • Materials Science(all)
  • Mechanical Engineering

Fingerprint

Dive into the research topics of 'IFE liquid wall response to the prompt X-ray energy deposition: Investigation of physical processes and assessment of ablated material'. Together they form a unique fingerprint.

Cite this