CFD Models for Liquid-Phase Chemical Reactors: Validation of PDF and Large-Eddy Simulations Using Stereo PIV and Reactive PLIF Experiments

调研：基于计算流体动力学（CFD）的宏观模型具有改进化学过程工业中反应器设计的潜力。 更好的反应堆设计还可以通过产生更少的有毒副产品来减少污染。 许多化学过程涉及快速化学反应，其产物分布受到湍流输送的影响。 对于这些系统，使用CFD有效地依赖于微观混合模型的开发和验证，所述微观混合模型用于描述亚网格尺度下湍流混合和化学反应之间的复杂相互作用。 商业CFD代码具有与模型开发和验证相关的缺点，在CFD能够充分发挥其开发环境友好、商业有效的化学技术的潜力之前，必须克服这些缺点。 PI将专注于开发湍流液相化学反应的CFD模型。 他们计划使用同步立体粒子图像测速仪（SPIV）和反应平面激光诱导荧光（RPLIF）在仔细控制的操作条件下获得两种典型反应器几何形状的液相内部湍流场和浓度场的实验数据。 在建模方面，他们将根据流动的大涡模拟（LES）和化学物质的概率密度函数（PDF）开发湍流反应流的CFD模型。 这些模型包含定义良好的未封闭的条款，将从SPIV和RPLIF数据提取两个典型的湍流：一个封闭的平面射流和封闭的突然膨胀平面射流。 更一般地说，在这个项目中获得的知识将提高在液相湍流中使用SPIV和RPLIF的同时速度和反应标量统计的测量技术的最新水平。更广泛的影响：PI在招募代表性不足的群体的学生参与他们的研究方面有着悠久的历史。 这些推广活动是由许多机构范围内的少数民族和妇女在爱荷华州州立大学招聘计划促进。 K-12学生将被邀请在PI的实验室工作作为暑期研究实习生。 减少因产品选择性差而造成的污染和有毒副产品是朝着开发用于生产燃料、材料、化学品和药品的环境友好、商业上有效的化学技术迈出的关键一步。

Research: Macroscopic models based on computational fluid dynamics (CFD) have potential for improving reactor design in the chemical process industries. Better reactor design can also lead to reducing pollution by producing less toxic byproducts. Numerous chemical processes involve fast chemical reactions for which the product distribution is affected by turbulent transport. For these systems, using CFD effectively depends on the development and validation of micromixing models needed to describe the complex interactions between turbulent mixing and chemical reactions at the sub-grid scale. Commercial CFD codes have shortcomings related to model development and validation that must be overcome before CFD can reach its full potential for developing environmentally benign, commercially efficient chemical technologies. The PIs will focus on developing CFD models for turbulent liquid-phase chemical reactions. They plan to obtain experimental data for turbulent flow field and concentrations fields inside the liquid phase for two canonical reactor geometries under carefully controlled operating conditions using simultaneous stereo-particle-image velocimetry (SPIV) and reactive planar laser-induced fluorescence (RPLIF). On the modeling side they will develop CFD models for turbulent reacting flows based on large-eddy simulation (LES) of the flow and probability density functions (PDF) for the chemical species. These models contain well-defined unclosed terms that will be extracted from SPIV and RPLIF data for two canonical turbulent flows: a confined planar jet and a confined sudden-expansion planar jet. More generally, the knowledge gained in this project will enhance the state of the art in measurement techniques for simultaneous velocity and reacting scalar statistics using SPIV and RPLIF in liquid-phase turbulent flows. Broader Impacts: The PIs have a long history of recruiting students from underrepresented groups to become involved in their research. These outreach activities are facilitated by many institution-wide minority and women recruitment programs at Iowa State University. K-12 students will be invited to work in the PI's laboratory as summer research interns. The reduction of pollution and toxic byproducts caused by poor product selectivity is a critical step towards the development of environmentally benign, commercially efficient chemical technologies for the production of fuels, materials, chemicals and pharmaceuticals.