Octo-TIGER / Radiation verification

Radiation test problems

M1 RK1 and FLD. Open a problem for its physical setup, comparison method, sources, and results at every completed resolution.

All requested simulations and postprocessing are complete1 completed runsl2-streaming_front-fld

FLD method scope. Grey radiation at physical light speed on CPU, backward-Euler diffusion/material exchange, and the Levermore–Pomraning limiter. Moving cases include first-order gas transport, radiation force/work, and a derived lab-frame flux with radiation enthalpy advection. Where supplied, analytic diffusion-limit references omit nonlinear-limiter and boundary-model effects. Thin streaming cases have no supplied analytic spatial FLD profile and use exact energy integrals instead. Paired M1 RK1 and FLD timings use different stability limits and do not establish performance at matched error.

Saved-state movie

Streaming Front · L2 · FLD backward Euler

121 stored states; 121 shown. Physical time: 0–0.2 s. Playback: 60 s.

Zero-order hold; no solution interpolation. Playback holds each saved numerical state over its time interval and includes endpoint holds.

All 121 snapshot times

Snapshot times: 0, 0.002, 0.004, 0.005, 0.007, 0.009, 0.01, 0.012, 0.014, 0.015, 0.017, 0.019, 0.02, 0.022, 0.024, 0.025, 0.027, 0.029, 0.03, 0.032, 0.034, 0.035, 0.037, 0.039, 0.04, 0.042, 0.044, 0.045, 0.047, 0.049, 0.05, 0.052, 0.054, 0.055, 0.057, 0.059, 0.06, 0.062, 0.064, 0.065, 0.067, 0.069, 0.07, 0.072, 0.074, 0.075, 0.077, 0.079, 0.08, 0.082, 0.084, 0.085, 0.087, 0.089, 0.09, 0.092, 0.094, 0.095, 0.097, 0.099, 0.1, 0.102, 0.104, 0.105, 0.107, 0.109, 0.11, 0.112, 0.114, 0.115, 0.117, 0.119, 0.12, 0.122, 0.124, 0.125, 0.127, 0.129, 0.13, 0.132, 0.134, 0.135, 0.137, 0.139, 0.14, 0.142, 0.144, 0.145, 0.147, 0.149, 0.15, 0.152, 0.154, 0.155, 0.157, 0.159, 0.16, 0.162, 0.164, 0.165, 0.167, 0.169, 0.17, 0.172, 0.174, 0.175, 0.177, 0.179, 0.18, 0.182, 0.184, 0.185, 0.187, 0.189, 0.19, 0.192, 0.194, 0.195, 0.197, 0.199, 0.2 s.

Arrows show derived FLD diagnostic flux -D grad(E); radiation momentum is not evolved. Arrows have equal length and show direction only.

Movies show saved numerical states. No nonlinear FLD spatial analytic reference is supplied for this benchmark; the M1 streaming profile is not an FLD reference. The final-time report includes exact invariant checks.

Central z=0+ radiation energy slice with faint cell mesh and equal-length flux direction arrows. Arrows show derived FLD diagnostic flux -D grad(E); radiation momentum is not evolved. Fixed color limits; actual stored Silo times held without solution interpolation. Movies show saved numerical states. No nonlinear FLD spatial analytic reference is supplied for this benchmark; the M1 streaming profile is not an FLD reference. The final-time report includes exact invariant checks. The maps show the full simulation domain without cropping.

Download MP4 · Rendering and timing metadata · Full run report

All campaign movies

Awaiting completed results
Thin positive-opacity closure comparison

Streaming wave

The same periodic sinusoidal energy used by the M1 wave evolves with gradient-driven FLD flux. FLD has no independently prescribed beam direction.

0 completed resolutions

Setup & all results →
Streaming front energy comparison
Energy comparison · 32³ cells · t = 2.000000e-01 s
Thin positive-opacity closure comparison

Streaming front

The same periodic bright half-domain used by the M1 front evolves with gradient-driven FLD flux. Its two edges do not represent one directed beam.

1 completed resolution

Setup & all results →
Awaiting completed results
Stationary flux-limited diffusion

Gaussian pulse

A periodized Gaussian energy perturbation diffuses in a prescribed stationary scattering medium. Flux is derived from the energy gradient.

0 completed resolutions

Setup & all results →
Awaiting completed results
Stationary flux-limited diffusion

Equilibrium sphere

A prescribed Gaussian emitter drives FLD in a stationary scattering medium, compared with its analytic steady linear-diffusion equilibrium.

0 completed resolutions

Setup & all results →
Awaiting completed results
Mixed-frame radiation hydrodynamics

Subcritical radiative shock

Gas density, momentum and thermal energy evolve with radiation transport, radiation force and paired gas/radiation work.

0 completed resolutions

Setup & all results →
Awaiting completed results
Mixed-frame radiation hydrodynamics

Radiating blast wave

Gas density, momentum and thermal energy evolve with radiation transport, radiation force and paired gas/radiation work.

0 completed resolutions

Setup & all results →
Awaiting completed results
Stationary flux-limited diffusion

Marshak wave

An incoming radiation bath heats initially cold, stationary material through coupled nonlinear FLD and material energy exchange.

0 completed resolutions

Setup & all results →
Combined plot reportBatch metadata