On the correlation of heat release rate in turbulent premixed flames
On the correlation of heat release rate in turbulent premixed flames
复制标题
湍流预混火焰放热率的相关性研究
DOI：
10.1016/j.proci.2010.06.090
复制
发表时间：
2011
影响因子：
4.7
通讯作者：
A. Dowling
中科院分区：
文献类型：
--
作者：
N. Swaminathan;R. Balachandran;G. Xu;A. Dowling
波动放热率变化率的两点空间相关性决定了明流火焰的声发射，这种相关性在过去的研究中没有直接解决。对湍流预混火焰的直接数值模拟和激光诊断结果进行了分析，研究了该关联函数和波动放热率的两点空间关联。分析表明，这些相关函数可以很好地用高斯函数表示。波动热释放率的积分长度尺度为1 ~ 2平面层流火焰热厚度δLo，且不受湍流雷诺数和旋流的影响。波动放热率变化率的长度尺度约为δLo/4。在上述长度尺度下，通过后处理RANS模拟计算的开放湍流预混火焰远场声压级与实测值有很好的对比。
Two-point spatial correlation of rate of change of fluctuating heat release rate dictates the sound emission from open turbulent flames and this correlation is not directly addressed in past studies. The results from Direct Numerical Simulation and laser diagnostics of turbulent premixed flames are analyzed to study this correlation function and the two-point spatial correlation of the fluctuating heat release rate. The analyses showed that these correlation functions can be represented very well using Gaussian functions. The integral length scale, ℓ, for the fluctuating heat release rate is about one to two planar laminar flame thermal thickness, δLo, and this is not influenced by turbulence Reynolds number and swirl. The length scale for the rate of change of fluctuating heat release rate is about δLo/4. The far field sound pressure levels of open turbulent premixed flames calculated by post processing RANS simulation results along with the above length scales compare very well with measured values.