Asymmetrically driven implosions

Vaughan, K.; McAlpin, S.; Foster, J. M.; Stevenson, R. M.; Glendinning, S. G.; Sorce, C.

doi:10.1063/1.3354113

Cited by 2 publications

(2 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the same vein, we have used an isobaric model of hot spot ignition and burn to understand the sensitivity of the propagation physics from hot spot to cold fuel. We set up the initial conditions in the hot spot as a R of 0.3 g/cm 2 and an initial temperature of 10 keV. We took a typical NIF ignition capsule, kept the fuel mass constant, and reduced the cold fuel density while increasing its temperature to maintain isobaric conditions.…”

Section: Fusion Applicationsmentioning

confidence: 99%

“…To validate the ability to model, and control, the implosion symmetry of a capsule in a hohlraum a number of experiments have been undertaken [2] at the University of Rochester using the OMEGA laser. Asymmetry has been introduced in various ways; changing the irradiation beam balance, changing the material at one end of the hohlraum, moving the capsule and introducing baffles.…”

Section: Model Validationmentioning

confidence: 99%

See 1 more Smart Citation

Overview of recent AWE fusion-related studies, experiments and facilities

Roberts

2013

EPJ Web of Conferences

View full text Add to dashboard Cite

Abstract. The presentation will describe the current status of modelling short and long pulse laser irradiation and its application to inertial fusion designs. Recent results will be described which give confidence in the modelling in specific regimes. An update will be given of the AWE ORION laser facility and the availability planned for academic access. AWE PERSPECTIVEFollowing the demonstration of the Laser in 1960, many laboratories considered the possibility of achieving fusion through laser heating of a DT plasma. The seminal paper by Nuckolls [1] in 1972 identified the significance of compression and the possibility of achieving ignition with only kilojoules of laser energy using a temporally shaped laser pulse. At AWE this stimulated the writing of the 1D and 2D simulation codes, NYM, to evaluate the concept independently. In 1973 AWE left the United Kingdom Atomic Energy Authority (UKAEA) and became part of the Ministry of Defence (MoD). During that decade the production of X-rays associated with laser irradiation, particularly of high-Z targets, became a topic of particular study as it offered the near-term prospect of studying aspects of weapon physics. The proposal was to use a high-Z hohlraum to both enhance laser absorption and to create a thermal radiation field. At this time the concept was classified and little was published. The conversion to thermal X-rays also offered a route to achieving fusion but higher energy seemed to be needed so experiments were proposed using the environment of an underground nuclear test. In parallel, the case for a TW Nd laser was accepted and the HELEN laser was opened in 1979. During the 1980s HELEN confirmed the approach of using high power lasers to study material properties at temperatures of around 100 eV together with the ability to study radiation transport and radiation hydrodynamics. The available energy (2× 1kj, 1ns, 1 ) meant that quantitative measurements of these more integrated aspects were difficult and the hohlraum temperatures achieved were somewhat lower than originally anticipated, due primarily to non-LTE effects. Subsequently temperatures in excess of 500 eV were demonstrated using CPA technology and conversion to 2 . On the fusion side, a UK experiment in 1982 was successful and gave some confidence in key physics aspects. In the 1990 s the UK ceased underground testing which gave greater impetus to the use of high energy lasers however the case for a 100 TW laser proved unaffordable. In the same decade (1993) AWE left the MoD and became contractorised under an arrangement known as GOCO (Government Owned Contractor Operated). During the 00 s decade this contract was re-competed and the contractor changed, in the same decade the case for ORION was accepted and construction started in 2006. This was coupled with an agreement between US and UK governments which provided access to NIF. The overall strategy is to use ORION primarily for material properties studies and NIF for more integrated experiments. We have also used the OMEGA laser at Roches...

show abstract

Section: Fusion Applicationsmentioning

confidence: 99%

Section: Model Validationmentioning

confidence: 99%

Overview of recent AWE fusion-related studies, experiments and facilities

Roberts

2013

EPJ Web of Conferences

View full text Add to dashboard Cite

show abstract

The onset of uninhibited heat conduction and non-local absorption in flux-limited laser-plasma ablation

2021

View full text Add to dashboard Cite

We study the developing temperature profile in planar laser-ablation in the limit of a completely ionized low-Z plasma. The problem is analyzed both analytically and numerically, assuming complete laser absorption by near-critical absorption and inverse bremsstrahlung absorption, and heat conduction by flux-limited diffusion. We show through dimensional analysis that the temperature in the resulting corona and conduction zones is characterized by scaling relations expressed through three dimensional parameters and depends on two dimensionless parameters. Our results form a phase diagram for the behaviors of the maximal temperature as a function of time at different phases of the flow. The phase boundaries curve describes the transition times as a function of the flux limiter. We show that for low values of the flux-limiter the flow behavior is highly dependent on local details of the laser absorption at the critical surface. Measured experimentally, the identified transition times between the different phases can be used to infer the characteristic value of the flux-limiter.

show abstract

Asymmetrically driven implosions

Cited by 2 publications

References 25 publications

Overview of recent AWE fusion-related studies, experiments and facilities

Overview of recent AWE fusion-related studies, experiments and facilities

The onset of uninhibited heat conduction and non-local absorption in flux-limited laser-plasma ablation

Contact Info

Product

Resources

About