Cylindrical Hohlraum benchmark used as a realistic IMC timing case. Top left: material-type field showing the absorbing wall regions and vacuum channel. Top right: characteristic Voronoi-cell size, with refinement near material-vacuum interfaces. Bottom left: three-dimensional view of the unstructured Voronoi tessellation, showing only the absorbing material regions. Bottom right: representative temperature slices—material temperature (bottom half) and radiation temperature (top half)—illustrating how radiation from the driven x = 0 boundary heats the capsule and wall regions.