Becker Nathan, Scheel J D, Cross M C, Ahlers Guenter
Department of Physics and iQCD, University of California, Santa Barbara, California 93106, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Jun;73(6 Pt 2):066309. doi: 10.1103/PhysRevE.73.066309. Epub 2006 Jun 23.
Experiments and simulations from a variety of sample sizes indicated that the centrifugal force significantly affects the domain-chaos state observed in rotating Rayleigh-Bénard convection-patterns. In a large-aspect-ratio sample, we observed a hybrid state consisting of domain chaos close to the sample center, surrounded by an annulus of nearly stationary nearly radial rolls populated by occasional defects reminiscent of undulation chaos. Although the Coriolis force is responsible for domain chaos, by comparing experiment and simulation we show that the centrifugal force is responsible for the radial rolls. Furthermore, simulations of the Boussinesq equations for smaller aspect ratios neglecting the centrifugal force yielded a domain precession-frequency f approximately epsilon(mu) with mu approximately equal to 1 as predicted by the amplitude-equation model for domain chaos, but contradicted by previous experiment. Additionally the simulations gave a domain size that was larger than in the experiment. When the centrifugal force was included in the simulation, mu and the domain size were consistent with experiment.
来自各种样本大小的实验和模拟表明，离心力显著影响在旋转瑞利 - 贝纳德对流模式中观察到的区域混沌状态。在一个大纵横比的样本中，我们观察到一种混合状态，在样本中心附近由区域混沌组成，周围是一个几乎静止的近乎径向滚动的环带，其中偶尔会出现类似波动混沌的缺陷。尽管科里奥利力导致区域混沌，但通过比较实验和模拟，我们表明离心力导致了径向滚动。此外，对于较小纵横比且忽略离心力的布辛涅斯克方程的模拟产生了一个区域进动频率(f)，近似为(\epsilon(\mu))，其中(\mu)近似等于(1)，这与区域混沌的振幅方程模型预测一致，但与先前的实验相矛盾。此外，模拟给出的区域大小比实验中的更大。当在模拟中包含离心力时，(\mu)和区域大小与实验一致。
