Large-eddy simulations of complex turbulent flows

大多数流体流动中都会出现湍流。它的复杂性是由于这样一个事实，即湍流传输主要是由于连贯的、螺旋状的运动(“旋涡”)，这些运动在性质上是确定性的，但出现在随机的时间和位置。例如，湍流传输在决定飞机阻力或热交换器内的热传递方面起着主要作用。由于流动分析的准确性和完备性较高，显式分解涡流的求解方法越来越流行，大涡模拟(LES)就是其中之一。这项建议首先将重点放在为大涡模拟开发改进的模型和方法，以减少其计算需求，并加速其向工业的过渡；第二，将大涡模拟应用于复杂的流动。我的团队最近开发了一种新的模型来参数化小涡[Piomelli等人，

Turbulence occurs in most fluid flows. Its complexity is due to the fact that turbulent transport is mostly due to coherent, whorl-like motions (“eddies”), which are deterministic in character, but appear at random times and locations. Turbulent transport plays the primary role in determining, for instance, the drag of an aircraft or the heat transfer in a heat exchanger. Solution methods in which the eddies are explicitly resolved are gaining popularity because of the higher accuracy and completeness with which the flow can be analyzed; among them is the large-eddy simulation (LES). This proposal will focus, first, on the development of improved models and methodologies for LES, to decrease its computational demands and accelerate its transition to industry; second, on the application of LES to complex flows. My group has recently developed a new model to parameterize the small eddies [Piomelli et al.,