摘要
非线性声流旋涡在加速热、质传输过程和清除固体表面积灰等方面具有显著的优势。为探究换热管声边界层外非线性声流旋涡的流场特性,采用Nyborg极限滑移速度法数值模拟了平面驻波声场和行波场中二维换热管周围的非线性声流现象。与经典Rayleigh声流的解析解对比,验证了数值方法的可行性。数值计算表明,在驻波场中,换热管处于声压波节和声压波腹位置时,换热管外分别呈现出4个和8个轴对称分布的声流旋涡结构;当换热管偏离声压波节或声压波腹位置时,换热管外的声流旋涡结构不再呈轴对称分布。滑移速度分布的波峰和波腹总个数决定了声流旋涡的个数。在行波场中,声流旋涡的流场特性与声波频率f和声压级L呈现出强的非线性依赖关系,声流强度满足:U_(2 max)=6.95388e^(−72)L^(33.50669)f^(−0.98828)。
The nonlinear acoustic streaming vortex has significant advantages in accelerating the process of heat and mass transfer and removing ash from solid surface region.In order to investigate the flow field characteristics of the nonlinear acoustic streaming vortex outside the acoustic boundary layer of the heat exchanger tube,the Nyborg limit slip velocity method is used to simulate the nonlinear acoustic streaming around the two-dimensional heat exchanger tube in the plane standing wave sound field and the traveling wave field.Compared with the analytical solution of the classical Rayleigh acoustic streaming,the feasibility of the numerical method is verified.The numerical calculation shows that there are 4 and 8 axisymmetric acoustic streaming vortex structures outside the heat exchanger tube in the standing wave field when the heat exchanger tube is in the position of the sound pressure node and the belly of the sound pressure wave,respectively.The acoustic streaming vortex structure outside the heat exchanger tube is no longer axisymmetric distribution when the heat exchanger tube deviates from the sound pressure wave node or the position of the sound pressure wave belly.The number of wave peaks and belly of slip velocity distribution determines the number of acoustic streaming vortices.In the traveling wave field,the flow field characteristics of the acoustic streaming vortex show a strong non-linear dependence on the sound frequency and sound pressure level,and the acoustic streaming intensity satisfies:U_(2 max)=6.95388e^(−72)L^(33.50669)f^(−0.98828).
作者
杨延锋
姜根山
赵文嘉
刘月超
YANG Yanfeng;JIANG Genshan;ZHAO Wenjia;LIU Yuechao(School of Energy Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,China;School of Mathematics and Physics,North China Electric Power University,Beijing 102206,China;Department of Mathematics and Physics,North China Electric Power University,Baoding 071003,China)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2022年第7期1958-1968,共11页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.12074118,No.11674093)
河北省自然基金资助项目(No.A2019502160)
声场声信息国家重点实验室资助项目(No.SKLA201808)。
关键词
声边界层
非线性
声流
旋涡
数值模拟
acoustic boundary layer
nonlinearity
acoustic streaming
vortex
numerical simulation
作者简介
杨延锋(1991-),男,博士研究生,主要从事非线性声学等方面的研究,E-mail:yyf2018@ncepu.edu.cn;通信作者:姜根山,男,教授,博士生导师,E-mail:gsjiang@ncepu.edu.cn。
