Математичне моделювання процесів кондуктивного і радіаційного теплообміну під час пожежі в соснових лісах

Abstract

A mathematical simulation of heat transfer process in a pine needle as a result of heat exchange by the contact of one of the ends with a a high temperature object such as glowing piece of wood, a spark, a cigarette end was carried out. The dependences of temperature on distance and time without and with convective heat exchange between a lateral needle surface and air were obtained. As the result of modeling we established that heat transfer process is more intense in a dry needle and a fixed-length needle part heats to the auto ignition temperature faster for dry needles, which indicates its greater fire danger than live one. The mathematical model of pine needle heating by radiation heat transfer from a surface fires flame was also developed. The temperature dependence on heating time for the heat radiation source as rectangle was obtained. Using the dependence for pine needles the heating time to auto ignition temperature was calculated.