Wave motion in subway or tunnel fire is an intrinsic property of smoke.As the pressure of smoke changes with mass of certain power,a kind of linear wave equation for smoke can be derived from the conservation equation...Wave motion in subway or tunnel fire is an intrinsic property of smoke.As the pressure of smoke changes with mass of certain power,a kind of linear wave equation for smoke can be derived from the conservation equations of its mass and momentum,under nearly homogeneous zone assumption.The smoke movement of 4 subway fires was simulated with Airpak.By fitting the pressure-mass functions to the simulated data,wave equations of the smoke were derived,and wave motions of smoke were thus validated.It can be seen that smoke wave is a kind of mass wave,whose velocity is inversely proportional to smoke mass,and wave of a bigger fire propagates slower.展开更多
Forest fags in China are very serious in recent years. Few fires occurred formerly in Southeast Tibet, but now forest fires in this region occur frequently. This natural environment of the region is unique. Forest fir...Forest fags in China are very serious in recent years. Few fires occurred formerly in Southeast Tibet, but now forest fires in this region occur frequently. This natural environment of the region is unique. Forest fires are very easy to occur in the dry seasons due to the influence of the southwest monsoon, Because over-mature forest in this region accounts for much proportion, the forest ecosystem is frail. Once destructed by forest fags, it is very extremely difficult to restore. Fire season in this area is in winter and spring. But in the special year, forest fires can also occur in the hot summer. Fire Season lasts from October to next February, even to April in an individual arid year. Most of the fires in this area are surface fires, and crown fires can occur after long time drought.展开更多
Analysis of nature environmental condition and evalwtion of selection and integration ofteclmiques have been carried out in Daxing’an mountains from 1987. The character of soil generaion in this area is influenced by...Analysis of nature environmental condition and evalwtion of selection and integration ofteclmiques have been carried out in Daxing’an mountains from 1987. The character of soil generaion in this area is influenced by the frigid, coniferous forest vegetation, weather, glacier and late soil formation process. Syntliesis teclmiques for high yield plantation include high seedling quality,suitable site preparation and eftbctive protectioll measures for yoimg trees.展开更多
文摘Wave motion in subway or tunnel fire is an intrinsic property of smoke.As the pressure of smoke changes with mass of certain power,a kind of linear wave equation for smoke can be derived from the conservation equations of its mass and momentum,under nearly homogeneous zone assumption.The smoke movement of 4 subway fires was simulated with Airpak.By fitting the pressure-mass functions to the simulated data,wave equations of the smoke were derived,and wave motions of smoke were thus validated.It can be seen that smoke wave is a kind of mass wave,whose velocity is inversely proportional to smoke mass,and wave of a bigger fire propagates slower.
基金Supported by NSFC Project (No. 30371170) and the fund of Forest Protection Laboratory, State Forestry Administration.
文摘Forest fags in China are very serious in recent years. Few fires occurred formerly in Southeast Tibet, but now forest fires in this region occur frequently. This natural environment of the region is unique. Forest fires are very easy to occur in the dry seasons due to the influence of the southwest monsoon, Because over-mature forest in this region accounts for much proportion, the forest ecosystem is frail. Once destructed by forest fags, it is very extremely difficult to restore. Fire season in this area is in winter and spring. But in the special year, forest fires can also occur in the hot summer. Fire Season lasts from October to next February, even to April in an individual arid year. Most of the fires in this area are surface fires, and crown fires can occur after long time drought.
文摘Analysis of nature environmental condition and evalwtion of selection and integration ofteclmiques have been carried out in Daxing’an mountains from 1987. The character of soil generaion in this area is influenced by the frigid, coniferous forest vegetation, weather, glacier and late soil formation process. Syntliesis teclmiques for high yield plantation include high seedling quality,suitable site preparation and eftbctive protectioll measures for yoimg trees.
