Study On Water Movement During Combustion Process Of Wood

The combustion process of wood is a complicated process, including a series of chemical and physical changes. Water movement can determine on not only the development of combustion flame but also the situation of combustion. It can provide some theoretical bases for the further study on the mechanism of wood combustion and fire retarding treatment on wood.At first, the different factors which have influence on water movement during combustion process of wood are inspected by the orthogonal experimental program about five wood species, such as Pinus massoniana(masson pine). Cunninghamia lanceolata(Chinese fir), Schima superba , Castanopsis fargesii and Sasafras tzumu(Chinese sasafras) . Temperature and moisture content are measured constantly. The curve lines about temperature and moisture content are drawn according to the combustion time, at the same time the regression equations are inferred. Secondly, wood species, initial moisture content, transverse position, longitude position and the direction of combustion are analyzed together, and then interrelated mathematics models are gotten. In addition, organizations inside wood(masson pine, Chinese sasafras) that are gotten after burning are observed by the scanning electron microscope in order to find some changed characters. Moreover, heat transport was analyzed for the samples of masson pine and Chinese sassafras.It is shown that initial moisture content (IMC) is the most important factor which affects water movement, and the factor of species is second only to IMC. At the same time, as for the same species, among the factors which are influent on water movement during the combustion of wood, sapwood is better than heartwood; the direction regressive the fiber is better than the following fiber direction, top part is better than root part. Temperature is a cubic function of time of combustion, and moisture content does also that. The results showed that the pits affected directly on water movement during combustion process of wood, and the data are reliable which were obtained from the experiment.