标题： 二维固定和旋转箱中的湍流SPH模拟，具有无滑移边界条件 显示英文标题

标题： SPH simulations of turbulence in fixed and rotating boxes in two dimensions with no-slip boundaries

摘要： 在本文中，我们使用粒子方法SPH研究二维固定和旋转箱体中的衰减湍流。边界由边界力粒子指定，湍流由一组高斯涡旋引发。在固定箱体的情况下，我们恢复了Clercx及其同事使用高精度谱方法和实验获得的结果。我们的固定箱体结果也与Monaghan1和Robinson与Monaghan2使用SPH获得的结果非常一致。无滑移、正方形、固定边界中衰减湍流的一个特点是，由于边界上的粘性应力对流体的反应，流体的角动量随时间变化。我们发现，当箱体可以自由旋转，使得箱体和流体的总角动量保持恒定时，流体的角动量变化比固定箱体的情况小约500倍，最终的涡度分布也不同。我们还模拟了当箱体被强制以小和大罗斯比数旋转时湍流的行为，并如前所述由高斯涡旋引发湍流。如果在湍流引发后保持箱体旋转，我们发现，在旋转参考系中，动能、涡度和涡旋结构的衰减对箱体的角速度不敏感。另一方面，如果在湍流引发后允许箱体自由旋转，演化的涡旋结构则完全不同。 显示英文摘要

摘要： In this paper we study decaying turbulence in fixed and rotating boxes in two dimen- sions using the particle method SPH. The boundaries are specified by boundary force particles, and the turbulence is initiated by a set of gaussian vortices. In the case of fixed boxes we recover the results of Clercx and his colleagues obtained using both a high accuracy spectral method and experiments. Our results for fixed boxes are also in close agreement with those of Monaghan1 and Robinson and Monaghan2 obtained using SPH. A feature of decaying turbulence in no-slip, square, fixed boundaries is that the angular momentum of the fluid varies with time because of the reaction on the fluid of the viscous stresses on the boundary. We find that when the box is allowed to rotate freely, so that the total angular momentum of box and fluid is constant, the change in the angular momentum of the fluid is a factor ~ 500 smaller than is the case for the fixed box, and the final vorticity distribution is different. We also simulate the behaviour of the turbulence when the box is forced to rotate with small and large Rossby number, and the turbulence is initiated by gaussian vortices as before. If the rotation of the box is maintained after the turbulence is initiated we find that in the rotating frame the decay of kinetic energy, enstrophy and the vortex structure is insensitive to the angular velocity of the box. On the other hand, If the box is allowed to rotate freely after the turbulence is initiated, the evolved vortex structure is completely different.