Swaminathan Anand, Garrett Steven L, Poese Matthew E, Smith Robert W M
Graduate Program in Acoustics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
151 Sycamore Drive, State College, Pennsylvania 16801, USA.
J Acoust Soc Am. 2018 Oct;144(4):2334. doi: 10.1121/1.5063820.
This paper presents the results of an experimental investigation of the parametric stabilization of Rayleigh-Bénard convection through the imposition of sinusoidal vibration. The ability to dynamically stabilize Rayleigh-Bénard convection using acceleration modulation is of interest to groups who design and study thermoacoustic machines as the introduction of parasitic convection can have deleterious effects on the desired operation and thermodynamic efficiency of the device. These performance issues caused by suspected convective instability have been seen both in traveling wave thermoacoustic refrigerators and cryogenic pulse tube chillers. This paper reports the results of an experiment intended to determine the vibratory, fluidic, and geometric conditions under which a small, rectangular container of statically unstable fluid may be stabilized by vertical vibration with comparison to the computational methods of R. M. Carbo [J. Acoust. Soc. Am. , 654-668 (2014)]. Measurements are obtained using a large-displacement kinematic shaker of an original design with the convecting gas characterized using both thermal transport measurements and flow visualization employing tracer particles illuminated by a diode laser light sheet phase-locked to the shaker. These experiments are believed to be the first demonstrating the suppression of convection through vibration in rectangular containers.
本文介绍了通过施加正弦振动对瑞利 - 贝纳德对流进行参数稳定化的实验研究结果。对于设计和研究热声机器的团队而言，利用加速度调制动态稳定瑞利 - 贝纳德对流的能力备受关注，因为寄生对流的引入可能会对设备的预期运行和热力学效率产生有害影响。在行波热声制冷机和低温脉冲管制冷机中，都出现了由疑似对流不稳定性导致的这些性能问题。本文报告了一项实验的结果，该实验旨在确定在何种振动、流体和几何条件下，通过垂直振动可使装有静态不稳定流体的小型矩形容器实现稳定，并与R. M. 卡尔博的计算方法[《美国声学学会杂志》，654 - 668(2014)]进行比较。测量是使用一种原始设计的大位移运动激振器进行的，对流气体通过热传输测量和使用由与激振器锁相的二极管激光片照亮的示踪粒子进行流动可视化来表征。据信这些实验是首次证明在矩形容器中通过振动抑制对流。
