中文摘要：

针对Taconis振荡对低温液体测量造成严重干扰并且极大增强低温储液的漏热问题，基于计算流体动力学（cFD）模拟方法，对氦气为介质的单端开口细长管内发生的Taconis振荡进行研究，低温端和常温端的温度分别为8和300K．通过数值模拟，获得包括热流密度、声流分布等在内的热声参数和完整的Taconis热声起振过程，通过对管壁和气体介质之间的热量传递过程和时均热流密度以及管内声功分布进行分析，定量揭示Taconis振荡的发生机理．模拟结果表明，在线性热声理论中可以忽略的径向速度在Taconis振荡中不能被忽略，根据模拟结果将Taconis管边界层划分为发声区和耗散区2个区域，其中发声区为热声转换区域，耗散区以泵热损失和黏性耗散为主．

英文摘要：

Aiming at the issue that Taconis oscillation not only causes disturbing effect to the measurements cryogenic fluids but also increases thermal load significantly, Taconis oscillation in a thin quarter- wavelength tube filled with helium with one end at 8 K and the other end at 300 K was studied with computational fluid dynamics（CFD） method. By numerical simulation, wall heat flux, acoustic power flow distribution, the whole onset process of Taconis thermoacoustic oscillation and some other important parameters are obtained successfully. Taconis oscillation mechanism was revealed by studying the heat transfer process between the gas and tube wall, the wall heat flux, and the acoustic power distribution in the Taconis tube. It is shown that the radial velocity which is ignored in the linear thermoacoustic theory can＇t be ignored in Taconis oscillation simulation, the boundary luyer of Taconis tube can be divided into generating area and dissipating area based on the simulation results, and thermoacoustic conversion occurs in generating area while heat pumping and viscous loss dominate the dissipating area.