Institute of Aeronautical Technology, Japan Aerospace Exploration Agency (JAXA)
出版者
日本流体力学会
出版者(英)
Japan Society of Fluid Mechanics
雑誌名
Fluid Dynamics Research
巻
46
号
2
発行年
2014-02-05
抄録(英)
The stabilizing effect of longitudinal wall oscillation on two-dimensional channel flow is analytically investigated. Because the flow field has temporalperiodicity, stability can be described by the Floquet theory. To do so, a monodromy matrix is derived from a time-dependent Orr-Sommerfeld equation using the collocation method, and then stability is determined by the use of the Floquet exponents. Systems of this kind are governed by the frequency and amplitude of wall oscillation and by the Reynolds number Re, which is determined by the maximum velocity of flow and half the distance between two walls. For Reynolds numbers in the range 6000-10 000, there is a region where a stable Tollmein-Schlichting (TS) mode appears in the parameter space. When the amplitude of wall oscillation increases, the disturbance wave is generally stabilized. This effect is large, especially for the TS mode. Consequently, the primary mode of unstable disturbance is changed from the TS mode to oblique modes.
(C) 2014 The Japan Society of Fluid Mechanics and IOP Publishing Ltd. Received 4 April 2013, accepted for publication 7 January 2014, published 5 February 2014.