论文标题
3D细菌悬浮液的密度波动和能量光谱
Density Fluctuations and Energy Spectra of 3D Bacterial Suspensions
论文作者
论文摘要
我们在实验中研究了整体\ textit {e的密度波动和能量光谱。大肠杆菌}浓度不同的悬浮液。我们的结果验证了三维（3D）湿活性流体中巨大数量波动的预测缩放定律。我们发现，即使在低浓度悬浮液中，这种缩放行为仍在小尺度上持续，远低于过渡浓度到主动湍流。我们的实验还支持对稀释型游泳者能量光谱的预测，并说明了大量限制中致密细菌悬浮液的主动湍流的光谱特性。通过比较活动湍流中的密度波动和动能，我们确定了在较大长度尺度上这两个量之间的通用密度无关和尺度不变的相关性。
We experimentally study density fluctuations and energy spectra of bulk \textit{E. coli} suspensions of different concentrations. Our results verify the predicted scaling law of giant number fluctuations in three-dimensional (3D) wet active fluids. We find that such a scaling behavior persists at small scales even in low concentration suspensions well below the transition concentration to active turbulence. Our experiments also support the prediction on the energy spectra of dilute pusher swimmers and illustrate the spectral properties of the active turbulence of dense bacterial suspensions in the bulk limit. By comparing density fluctuations and kinetic energy in active turbulence, we identified a universal density-independent and scale-invariant correlation between the two quantities across a wide range of length scales.
