论文标题
湍流的原星盘中尘埃流的共振阻力不稳定
The resonant drag instability of dust streaming in turbulent protoplanetary disc
论文作者
论文摘要
使用局部方法在小灰尘分数的极限下，研究了先前发现的粉尘流中尘埃流的谐振阻力不稳定性（RDI）的阻尼。圆盘中的湍流分别以气体和灰尘运动方程式的有效粘度和扩散率表示。在Schmidt编号的标准情况下（有效粘度与扩散性的比率）SC = 1，惯性波（IW）（IW）和流式尘埃波（SDW）的描述减少了RDI的描述，而互相共振的流动粉尘波（SDW）彼此之间存在共鸣，这表明抑制解决方案与单打溶液的增长频率仅通过添加型号的增长频率而有所不同。 RDI在阈值粘度下被完全抑制，该粘度在分析上进行了估计，首先是径向漂移，接下来，用于垂直灰尘沉降，最后，在沉降的情况下，结合了灰尘的径向漂移。在最后一个情况下，RDI生存到最高的阈值粘度，对于较小的固体而言，过量较大。一旦SC \ neq 1，就会出现针对粉尘沉降背景上耗散性扰动的新不稳定性。准性质的这种不稳定性称为沉降粘性不稳定性（SVI）。只要SC> 1（SC <1），类似于SDW（IW）（IW）的模式就会在长浪区域中生长。 SVI导致阈值粘度的额外增加。
Damping of the previously discovered resonant drag instability (RDI) of dust streaming in protoplanetary disc is studied using the local approach to dynamics of gas-dust perturbations in the limit of the small dust fraction. Turbulence in a disc is represented by the effective viscosity and diffusivity in equations of motion for gas and dust, respectively. In the standard case of the Schmidt number (ratio of the effective viscosity to diffusivity) Sc = 1, the reduced description of RDI in terms of the inertial wave (IW) and the streaming dust wave (SDW) falling in resonance with each other reveals that damping solution differs from the inviscid solution simply by adding the characteristic damping frequency to its growth rate. RDI is fully suppressed at the threshold viscosity, which is estimated analytically, first, for radial drift, next, for vertical settling of dust, and at last, in the case of settling combined with radial drift of the dust. In the last case, RDI survives up to the highest threshold viscosity, with a greater excess for smaller solids. Once Sc \neq 1, a new instability specific for dissipative perturbations on the dust settling background emerges. This instability of the quasi-resonant nature is referred to as settling viscous instability (SVI). The mode akin to SDW (IW) becomes growing in a region of long waves provided that Sc > 1 (Sc < 1). SVI leads to an additional increase of the threshold viscosity.
