Investigation of Nonpremixed, Reacting Turbulent Flows

KOSALY CTS-9415280该程序是PI目前用直接数值模拟方法研究化学反应湍流的继续。PI建议扩展他们目前的工作，以研究差异扩散和热释放对湍流混合和湍流中化学反应的小尺度结构的影响。具体地说，这项研究将包括将直接数值模拟应用于以下湍流、非预混反应流：(1)均匀的、带有化学反应和微分扩散的衰减湍流的直接数值模拟。不考虑散热影响。(2)具有化学反应的空间演化近似均匀湍流的数值模拟。热释放效果将被包括在内。我们将考察濒临灭绝的条件闭合模型(CMC)的适用性，以及CMC模型的基本预测能力。(3)具有化学反应的空间演化湍流射流的数值模拟。在CMC模型中，将考虑热释放和一步化学反应，以及条件矩在横向坐标上独立的重要假设。

ABSTRACT KOSALY CTS-9415280 The proposed program is a continuation of the PI's current investigations of chemically reacting turbulent flows using direct numerical simulation (DNS). The PIs propose to extend their present effort in order to investigate the effects of differential diffusion and heat release on the small scale structure of turbulent mixing and chemical reactions in turbulence. Specifically the investigation will include the application of DNS to the following turbulent, non-premixed reacting flows: (1) DNS of homogeneous, decaying turbulence with chemical reaction and differential diffusion. No heat release effects considered. (2) DNS of spatially evolving, approximately homogeneous turbulence with chemical reaction. Heat release effects will be included. The applicability of the conditional closure model (CMC) near extinction will be examined as will the radical prediction capability of the CMC model. (3) DNS of a spatially-evolving, turbulent jet with chemical reaction. Heat release and a one step chemical reaction will be considered as will the important assumption of the independence of the conditional moments on the transverse coordinate in the CMC model.