This page runs conservative general-relativistic magnetohydrodynamics for a magnetized accretion torus and tracks the divergence-free magnetic-field constraint as the solve advances. It runs entirely in your browser with no install, deterministic on a fixed input, so a researcher can inspect the constraint behavior of a constrained-transport scheme before committing time on an HPC cluster. GDBS is a bridge to HPC, not a surrogate for it.
|div B| = 2.4e-4 (GPU), < 1e-12 (CPU Orszag-Tang)
Conservative GR-MHD with face-centered constrained transport: a magnetized torus keeps the divergence-free constraint at |div B| = 2.4e-4 (GPU) and below 1e-12 (machine zero) on the CPU Orszag-Tang test.
The scheme is conservative GR-MHD using face-centered constrained transport. The magnetic field is stored on cell faces and evolved so that the discrete divergence of B is preserved as the solution advances. The magnetized torus is evolved on the GPU; the relativistic Orszag-Tang configuration is run on the CPU as an independent constrained-transport check. The reported quantities are the residual magnitudes of the divergence-free constraint, |div B|, measured during the runs.
Divergence-free preservation is a numerical self-check (a constraint that must stay zero), not a data comparison against a published measurement. This is a 2D-axisymmetric Cowling testbed for method development. Production accretion runs stay on HPC.
Open the engine and run it deterministically in your browser:
Open GRMHD (HARM) in GDBS See the full validation table