Flammable Vapor Storage: 2D Concentration Field & Hot-Spot Risk

This 2D companion to the 3D flammable-vapor storage room asks a question the 3D lumped-concentration model cannot answer: where in the room does the vapor actually sit? Instead of one instantly-mixed concentration number, this simulator solves the real 2D diffusion–advection–reaction equation across the room's floor plan on a finite-difference grid, with the leaking drum as a localized source and the extraction fan as a localized sink using the same evaporation and ventilation physics as the 3D model. The result is a genuine concentration field: a hot pocket forms right around the drum that can sit deep inside the explosive range long before the room-wide average would ever suggest danger, while the zone right at the extractor stays close to the well-mixed model's predicted steady state — exactly the gap real industrial-hygiene surveys are designed to catch. Adjust leak severity, ambient temperature and extraction rate to watch the field build and drain, and test an ignition source at the worst local pocket rather than a single room-wide value.