combustion of wood shavings

Özer AYDIN

Hi,In my case, wood sawings is in a cylindirical volume and is not moved or transported by air flow. Air is blowed from bottom of the cylinder. Air passes thorugh the wood sawing.At the experimental setup wood is ignited by electircal heater.The energy for ignition is given for a few minutes. Meanwhile air is blowed through the wood. Then heater is shut down and air is blowed continously.The combustion zone propagated to the upper part of the cylinder.This a unsteady problem.It can be solved as a unsteady problem or a steady problem.As a steady problem, the combustion front propagation front velocity will not be output. If it is solved a steady problem, I think wood mass flux should be given as a data.As an unsteady problem, a certain amount of wood sawing must be in the cylindrical volume and the propagation of combustion should be modelled.For us the best is the unsteady solution.So we have problem to choose the proper models for both steady and unsteady solution.If you give some advises for modelling, it will bie very helpful.Thank you very much.