方形竖槽道内受浮力驱动旋转火焰及热流场特性

Characteristics of Thermal Flow Field and Swirling Flame due to Buoyancy in a Quadrate Shaft

针对受限空间内受浮力驱动的旋转火焰及热流场所表现出的复杂特性,采用实验方法对一尺寸为2.0m×2.0m×15.0m的有单侧缝的方形竖槽道内产生的火旋风流场进行研究,并对中心轴线上的温度进行测量。同时采用基于大涡模拟技术的数值方法进行了模拟计算,验证了构建的数学模型对于预测该方形竖槽道内的热流场的准确性。通过对火旋风在稳定期内热流场的平均压强、温度、密度在高度方向和径向的分布情况和变化规律的分析,验证了火旋风的斜压影响机制,确定了温度和压力在高度上的分层特性,并发现等密度面更易于表现旋转火焰的变化情况。整个实验与数值计算结果都可为受限空间内的旋转火焰研究提供参考。

In order to interpret the characteristics of the thermal flow field and swirling flames in an enclosure, an experiment in a quadrate shaft having size of 2.0m×2.0m×15.0m with a single corner gap was conducted, and the temperature along the central axis of the shaft was measured. Besides, in order to verify whether or not the numerical method with Large Eddy Simulation （LES） is able to predict the thermal flow field, the predicted temperature was compared with the experimental data. Furthermore, the distributions of average pressure, temperature, and density along the lines of height and radius are obtained, when the fire swirl is steady. And the baroeliny of the swirling flames due to buoyancy is analyzed. The stratification of the temperature and pressure with height are concluded. These results provide a reference for the research on the swirling flames driven by buoyancy in an enclosure.