FLUENT培训教材8物理模型.ppt

总结 模拟运动部件有五种方法 单参考坐标系法 多参考坐标系法 混合平面法 滑移网格法 动网格法 前三种方法主要用于稳态，而滑移网格和动网格本质是瞬态的 要激活这些模型，将流体域由固定改为动坐标系或动网格设置 大多数物理模型和动坐标系或动网格法兼容（如多相流、燃烧、传热等） 谢谢 A Pera Global Company ? PERA China Let’s go ahead and get started with an introductory discussion of combustion models and the different kinds of tools that are within Fluent to handle combustion applications. There’s a wide range of problems that can be handled by the Fluent software for homogeneous as well as heterogeneous reacting flows that you might find, for example, in furnaces, boilers, process heaters, gas turbines and rocket engines. So, typically, people who are using our code for these kinds of applications are interested in a number of different results. They’re interested in looking at the flow field and the mixing characteristics for fuel and oxidizer within their application. They’re also interested in the temperature field to answer question like: Is the temperature uniform? Are there hot spots? What’s the maximum temperature within the device? They’re looking at species concentrations, and in particular, oftentimes people are interested in looking at pollutant emission, like NOX, and at particulate dispersion. So there’s a wide range of interests by people that are using our software for combustion modeling and we have a variety of physical models and tools available to handle these problems. So we’re looking for practical approaches to deal with these reaction rates in turbulent flows. So, you can use reduced chemical mechanisms and that’s what is done in the finite rate combustion model. We can also decouple the chemistry from the turbulent flow and mixing problem and we do that with the PDF model and the laminar flamelet model. We can also utilize what’s called a progress variable to perform this decoupling, and that’s what’s the Zimont model is about. We’ll take a look at each of these models in more detail later on. Computational fluid dynamics (or CFD) has been used to examine problems in