these-beccantini
A matrix free approach for multicomponent reactiveall-speed flows on complex and large geometriesThe use of Computational Fluids Dynamics (CFD) for industrial applications often impliesthe capability of dealing with geometries which are large with respect to the characteristic di-mensions oftheinvolved physical phenomena. Such situationariseswhen wewant todeterminepressure loads generated by a hydrogen-air combustion which might occur in a nuclear reactorcontainmentduringapostulatedLossofCoolantAccident. Indeed, ifweconsidertheEuropean3 3Pressurized Reactor, the free volume of the building is about 75000 m , i.e. (42m) . We arein similar situations when we want to determine pressure loads caused by a so-called VaporCloud Explosion which might occur in the case of accident in an hydrogen production plant(like the ones coupled with high temperature gas reactors [8]): even in this case, the domainof interest can have the dimension of hundreds of meters. Characteristic physical lengths aremuch smaller. To have an idea of the mesh dimension we need for the “direct simulation” offlame propagation and deflagration-to-detonation transition (DDT), see for instance [6].We can avoid the direct simulation if we consider the flame as infinitely thin, neglect thediffusion phenomena and model their effect, for instance, introducing phenomenological lawsfor the flame speed. Indeed, as explained in [5], pressure loads can be correctly predicted asthe flame speed is ...