V-BO-05 — PMMA-on-Kaowool burnout on a fixed mesh under in-depth absorption stops at the first interior void

Tags: eulerian, burnout, depletion, beer_lambert, coupled

References:

• MaCFP-2 PMMA gasification case (NIST), 50 kW/m²

Problem statement

The V-BO-01 deck, in-depth absorption included, on a fixed mesh. The temperature maximum of the PMMA lies below the surface, so the surface cell reacts slowest: it persists as a low-density skin while the cells beneath it empty, and the layer gasifies from within. A void cell conducts with the gas conductivity and absorbs nothing, and nothing in the model carries heat across a void, so the flux transmitted through the void column would heat the substrate beneath it far outside the property bracket.

The depletion callback stops a fixed-mesh solve when a live cell below the top live cell becomes a void (matrix volume fraction below 1e-4). The run must stop between 330 and 345 s with the interior-void warning, before any park, with the maximum live-cell temperature below 1000 K. The solve ends with retcode Terminated.

Quantities of interest (n = 120)

Solver configuration