Effect of harmonic heat flux variation on solid material piloted ignition

Aymeric Lamorlette (1)

1 M2P2 - Laboratoire de Mécanique, Modélisation et Procédés Propres

This study aims at modeling the effect of incoming heat flux fluctuations on solid material ignition. In order to propose a general methodology that can be applied to any kind of solid target, kernels accounting for the target temperature response regarding an incoming heat flux are developed for thermally thick and thin solids with low or high thermal inertia. The expected behavior of these different target types during ignition is therefore discussed, based on the kernel analysis. A Fourier decomposition of the incoming heat flux is then used to calculate the target response to harmonic heat fluxes, allowing description of the different target type behavior. Finally, the practical meaning of these harmonic fluctuations and their effects on target ignition is discussed based on the previous analytical results, allowing to discriminate situations where ignition time is predictable from situations where ignition time is unpredictable.

Mots clés: Piloted ignition; harmonic time-varying heat flux; ignition predictability

Domaines: Thermique [physics.class-ph]; Thermique [physics.class-ph]

Aymeric Lamorlette. Effect of harmonic heat flux variation on solid material piloted ignition. 2013. ⟨hal-00839634v3⟩