【摘要】：針對火災(zāi)場氣流與焰域溫度空間耦合變化時的結(jié)構(gòu)響應(yīng),通過考慮氣流流速及焰圍空間和結(jié)構(gòu)物高度的相互作用效應(yīng),建立了焰流場環(huán)境火災(zāi)模型。采用時間增量迭代的方法計(jì)算了焰流場溫度,研究了復(fù)合邊界控制方程和對流換熱與流速之間的相互關(guān)系。分析了流場中結(jié)構(gòu)迎流面和側(cè)流面溫度分布狀態(tài),研究了混凝土空心薄壁墩的環(huán)境火災(zāi)場景,建立了焰流場結(jié)構(gòu)耦合模型,揭示了焰流效應(yīng)下混凝土空心薄壁墩三維空間火溫時變分布規(guī)律。研究結(jié)果表明:火延時間為120min,流速為3m·s-1時,近火點(diǎn)溫度比其他流速下溫度約高100℃,流速對火源溫度呈非線性影響狀態(tài);500℃以上的高溫層在混凝土空心薄壁墩迎火面分布深度僅為7cm,在豎向荷載作用下空心薄壁墩外層迎火面混凝土易產(chǎn)生層剝現(xiàn)象;迎流面溫度遠(yuǎn)高于側(cè)流面溫度,背火面溫度無變化;穩(wěn)態(tài)低流速場中流速的變化可改變不同溫度區(qū)域的分布,并擴(kuò)大迎火面高溫區(qū)面積。
[Abstract]:In view of the structural response of the air flow in the fire field and the temperature coupling in the flame region, the fire model of the flame flow field is established by considering the interaction effect of the flow velocity, the flame circumference space and the height of the structure. The temperature of flame flow field is calculated by time increment iteration method. The composite boundary control equation and the relationship between convection heat transfer and velocity are studied. In this paper, the temperature distribution of the front and side flow surfaces in the flow field is analyzed, the environment fire scene of the concrete hollow thin-walled pier is studied, and the structure coupling model of the flame flow field is established. The time-varying distribution of fire temperature in three-dimensional space of hollow thin-walled concrete pier under flame effect is revealed. The results show that the temperature near the fire point is about 100 鈩，

本文編號：2173221