Multidimensional modeling of pyrolysis gas transport inside charring ablative materials

The behavior of pyrolysis gas transport in arcjet test samples is numerically studied. The simulation of the pyrolysis gas flow inside a porous material is presented, using two different geometries. The effects of allowing the gas to flow out of the sidewall are especially highlighted. Results show that the flow inside the test article is complex, and that the zero-dimensional or one-dimensional assumption made in most material response codes are not necessarily valid for certain geometries. The importance of three-dimensionality for modeling an ablative test article is addressed.