不同扩散效应下一维湍流模拟氢气-空气射流的扩散火焰

摘要

应用一维湍流模型(ODT)来研究湍流射流氢气-空气扩散火焰,研究过程中采用详细化学反应机理和多分量输运属性.对于火焰长度、主要燃烧产物及温度的预测较好地符合了实验结果.ODT模拟结果产生了较高的近场扰动.提出了一种旨在通过修改涡事件选择过程从而提高ODT模型精度的新观点.在模拟中检验了微分扩散效应,结果显示当前火焰中存在着显著不同的扩散效应.%One-dimensional turbulence (ODT) was implemented for studying jet hydrogen-air diffusion flames with detailed chemi cal reaction mechanism and multicomponent transport properties. ODT prediction of flame length was in excellent agreement with measured value. ODT predictions of major species and temperature were compared with experiments, and thus reasonable agreements were obtained, even if fluctuations were higher in the nearfield. A new viewpoint was presented to improve the accuracy of ODT model by modifying the procedure of eddy selection. The effects of differential diffusion were examined. The results show that the effects of differential diffusion are pronounced in the present flame.