DDDAS-SEP: Application of DDDAS to Assessment of Thermal Systems Using Combined Experiment and Simulation

该项目将采用动态数据驱动应用系统（DDDAS）方法，使用实验和模拟相结合的方法来评估流体热系统。涉及流体热系统的工程应用的特点是复杂的三维流动，在关键子系统中的边界条件的知识不完整和有限的访问实验诊断。一个例子是涡轮风扇发动机中的燃烧器，其中燃烧器筒表面上的热边界条件不是先验已知的（即，表面温度分布是未知的），并且光学诊断的使用受到严重限制。基于DDDAS的方法协同实验和模拟，以实现对流体热系统的评估;特别是，以确定表面温度分布到合理的精度水平。 具体应用是紊流射流垂直注入亚音速或超音速平衡紊流边界层。通过与燃烧器或炉类比，假设实验诊断限于受限区域内的光学测量（具体地，在各种波长处的二极管激光器吸收率）（以模拟实际配置中的受限访问，例如，燃烧器）。模拟将使用三维雷诺平均Navier-Stokes方程和k-e湍流模型进行。非反应流和反应流都将被考虑。使用实验和模拟评估流体热系统的基于DDDAS的方法在工程系统中具有潜在的更广泛的应用（例如，化学和生物化学工程、土木工程等）。

The project will apply the Dynamic Data Driven Applications Systems (DDDAS) methodology for assessment of fluid-thermal systems using combined experiment and simulation. Engineering applications involving fluid-thermal systems are characterized by complex three-dimensional flows with incomplete knowledge of boundary conditions in critical subsystems and limited access for experimental diagnostics. An example is the combustor in a turbofan engine wherein the thermal boundary conditions on the combustor can surface are not known a priori (i.e., the surface temperature distribution is not known) and access for optical diagnostics is severely limited. The DDDAS-based methodology synergizes experiment and simulation to achieve an assessment of the fluid-thermal system; in particular, to determine the surface temperature distribution to a reasonable level of accuracy. The specific application is a turbulent jet injected normally into a subsonic or supersonic equilibrium turbulent boundary layer. By analogy to a combustor or furnace, the experimental diagnostics are assumed to be limited to optical measurements (specifically, diode laser absorbance at various wavelengths) within a restricted region (to simulate limited access in the actual configuration, e.g., combustor). Simulations will be performed using the three-dimensional Reynolds-averaged Navier-Stokes equations with the k-e model of turbulence. Both non-reacting and reacting flows will be considered.The proposed DDDAS-based methodology for assessment of fluid-thermal systems using experiment and simulation has potentially broader applications in engineering systems (e.g., chemical and biochemical engineering, civil engineering, etc).