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通讯作者:

瞿叶高,E-mail:quyegao@sjtu.edu.cn

中图分类号:O324;O322

文献标识码:A

文章编号:1672-6553-2023-21(6)-031-008

DOI:10.6052/1672-6553-2023-077

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目录contents

    摘要

    针对柔性管道内段塞流引起的结构大变形流致振动问题,本文采用分区强流固耦合方法建立了面向大变形两相流输运管道的双向流固耦合数值计算模型.基于流体体积法对气液两相流动界面进行追踪并结合任意拉格朗日-欧拉(ALE)动网格方法考虑流体域网格变形,同时采用有限元方法建立了柔性管道动力学模型,根据流体和管道壁面的相互作用构建强流固耦合计算模型.研究表明,在两相流作用下柔性管道的振动主要以类似一阶和二阶振动模态响应为主且会发生模态切换;模态切换与管内的液塞长度、液塞流动频率以及气液塞在管内的轴向分布有关;管道的大变形振动促进了短气塞的融合并显著改变了液塞的长度和频率,进而影响管道的振动和流型转变界限.

    Abstract

    In order to study the flow-induced vibration characteristics caused by gas-liquid two-phase flow in a flexible pipe with large deformation, a numerical simulation platform for partitioned fluid-structure coupling under the condition of the internal two-phase flow has been developed. The interface between the gas and liquid phases is tracked based on the volume of fluid method, and the mesh deformation of fluid domain is considered by the arbitrary Lagrangian-Euler (ALE) dynamic mesh technique. Meanwhile, the flexible pipe is established by the finite element method. The fluid domain and structural domain are coupled by adapting the coupling library preCICE. The results indicate that the and three types of mode switching are identified on the basis of the switching characteristics. The vibration of the large-deformation flexible pipe is dominated by the first order and second order oscillation modes. The mode switching mainly depends on the length, recurrence frequency and the axial distribution of liquid slug in the flexible pipe. The large deformation of the pipe promotes the fusion of the short bubble slug and changes the length of the liquid slug significantly, thus affecting the vibration amplitude and flow pattern transition boundary of the pipe.

  • 引言

  • 气液段塞流广泛存在于核电、石油化工、海洋工程等工业领域的管道中,如饱和蒸汽管道、油气混输管道和海洋管道等[1-2].这些管道大多为薄壁结构,气液段塞流与薄壁管道之间的相互耦合作用,可引发管道产生大变形的流致振动,引起管道疲劳损伤甚至导致管道爆裂,酿成重大安全事故[3-4].

  • 目前针对气液两相流诱导的管道流致振动研究主要集中在直管和曲管的小变形振动问题,针对柔性管的两相流大变形振动研究非常有限.Rodriguez等[5]通过实验研究了不同流型下水平管道的振动响应,发现其幅值取决于流动和结构参数,如混合流速、相体积分数和流型.Thorpe等[6]通过实验研究发现,长泡状流下水平管道的振动为窄带随机振动,而弹状流和环状流下则表现为周期性振动.Giraudeau等[7]研究了不同流型下两相流诱导的竖直U形管振动响应特性,发现泰勒气泡与液塞之间的动量急骤变化导致段塞流时管道振动幅值最大.Pettigrew[8]在研究两相流作用下竖直弯管的振动响应时,也发现段塞流引起的管道横向振动幅值远高于其他流型,而气泡和液塞对弯头的冲击频率与流体密度、相体积分数和动量通量等参数相关.Wang等[9]通过建立流固耦合模型,分析了严重段塞流诱导水平管-立管系统振动的机理,发现管道振动响应与严重段塞流的周期性有关.Zhu等[10]研究了不同流速、气液比的段塞流作用下的悬链线型立管的振动响应,分析了立管平面内振动中出现的模态切换现象.Hashimy等[11]发现了段塞流速是决定弹性管道振动的关键因素,振动位移随液相表观流速的增大而增大.Ma和Srinil[12-13]通过建立二维数值模型研究了段塞流诱导的弯曲柔性管道的振动响应,发现管道的多模态振动响应与段塞频率密切相关.

  • 气液两相流引起的管道大变形振动包含了复杂的强流固耦合机理,目前的研究大多只关注了气液两相流对管道振动的影响,鲜有分析管道振动对管内流动特性及流型变化的影响.Jin等[14]研究了摇摆振动状态下矩形管道内两相流的流动变化,发现摇摆振动降低了管内两相流压降且其含气率随摇摆角度和频率的增大而提升.曹夏昕和方红宇等[15-16]利用振动台研究了摇摆振动对竖直管、水平管内气液两相流动的影响,分析了振动对管内单相流的摩擦压降及气液两相流的流型、流型转变界限、界面含气率以及摩擦压降等参数的影响,发现振动会使管内气液两相流产生附加惯性摩擦力,增大管内的摩擦压降,并且通过对振动状态下流型转变机理的分析,给出了各流型之间的转变准则关系式.周云龙等[17]基于实验研究了起伏振动对水平直管内两相流流型的影响,通过对气液两相流压差波动的分析,发现振动状态下出现了特有的泡状流及沸腾波状流.Hibiki 和Ishii[18]发现管道的振动会促进泡状流中气泡之间的相互融合,但这种影响不足以改变泡状流的流型.肖秀等[19]发现泡状流在起伏振动状态下极不稳定,随着气相流速的增加逐渐向搅拌流转化,进而削弱管道的振动.常赫等[20]对非线性振动下水平管道内两相流流动特性进行研究,结果表明流体瞬时摩擦压降的波动幅度与振动频率和振幅呈正相关,且振动频率的影响效果大于振幅.

  • 综上,目前对于同时考虑气液两相流诱发的管道振动及振动对管内两相流流态的影响,缺少对双向流固耦合效应的深入分析.这类复杂的流固耦合现象在海洋工程及油气管道中普遍存在,尤其是不稳定的气液两相流流经非线性弯曲的柔性管道时,易激发柔性管道产生复杂的非线性多模态振动响应,这种复杂的多模态振动又会影响管内两相流的流动特性,甚至导致管内气液两相流型出现时空动态演变,进一步加剧柔性管道的振动.本文建立了两相流诱导的柔性管道大变形流固耦合模型,研究了不同表观流速和含气率工况下柔性直管内段塞流诱导振动的机理以及管道变形对两相流流动特性的影响,为两相流管道的设计、维护及振动抑制提供参考.

  • 1 理论模型和计算方法

  • 1.1 两相流数值模型

  • VOF(Volume of Fluid)模型[21]适用于描述界面特征长度远大于网格尺寸的两相流问题,对于具有明显相界面的流型如环状流和段塞流等具有很好的适应性.将气液两相视为单一不可压缩连续介质,不考虑相变和传热传质,则其连续性方程和动量方程可以表示为:

  • ρt+(ρU)=0
    (1)
  • (ρU)t+(ρUU)=-p+τ+ρg+Fsurf
    (2)
  • 其中,UFsurf分别表示速度和表面张力矢量,τ=μU+UT;密度ρ和黏度μ是相体积分数的函数,用下式计算:

  • ρ=αlρl+αgρg,μ=αlμl+αgμg
    (3)
  • 其中,α表示相体积分数,下标l和g分别表示液相和气相.

  • 为了使相界面保持足够的尖锐,本文通过一种人工的对流项(方程右侧第三项)来对相界面附近的相分数进行挤压,以抗衡数值耗散带来的相界面模糊性[22],其体积分数控制方程满足:

  • αt+Uα+α(1-α)|U|α|α|=0
    (4)
  • 在管内两相流问题中,表面张力会导致相界面处存在一个尖锐的压降.在动量方程式(2)右端添加表面张力项[23],其计算表达式为:

  • Fs=-σα|α|α
    (5)
  • 其中,σ为表面张力系数,这里取0.072kg/s2.

  • 本文采用标准k-ε模型和标准壁面函数分别考虑湍流和近壁面的影响.为了提高迭代求解的效率,采用压力隐式算子分割算法(PISO)对压力速度耦合方程进行求解计算.流体控制方程采用有限体积法进行离散,其中时间项采用一阶欧拉隐式进行离散,对流项则采用高斯积分的线性修正离散格式,压力梯度离散采用高斯积分的线性离散格式;体积分数方程中的对流项采用Gauss Vanleer格式,人工压缩项采用Gauss Interface Compression格式[24].

  • 1.2 柔性管道数值模型

  • 当流体充满管道时,柔性管道产生弯曲变形,而两相流时空分布规律的变化则会诱导管道产生振动.采用Green-Lagrange 应变和第二类Piola-Kirchhoff应力来考虑管道的大变形特性,基于非线性有限元法建立大变形弹性管道的结构动力学模型.忽略管道的热传导和热辐射,两相流作用下管道的有限元离散动力学方程为:

  • [M]{q¨}+[C]{q˙}+KL+KNL{q}={F}
    (6)
  • 式中,[M]表示质量矩阵,[C]表示阻尼矩阵,KL为线性刚度矩阵,KNL为结构非线性刚度矩阵.{q¨}{q˙}和{q}分别为节点加速度向量、速度向量和位移向量.{F}为流体激励力向量.

  • 1.2 流固耦合方法

  • 文中采用强分区隐式耦合迭代算法求解流固耦合问题并通过径向基函数(RBF)插值方法实现流体与结构之间的数据映射[25].在流固耦合交界面上需要满足速度协调和力平衡条件:

  • U-f=q˙¯s
    (7)
  • σ-fnf=σ-sns
    (8)
  • 式中,U-fq˙¯s分别为耦合界面上流体节点和结构节点的速度;σ-fnfσ-sns分别是流体和结构在耦合交界面上的应力.

  • 在给定时间步长的每次耦合迭代中,首先根据结构的动力学响应,结合网格重构的动网格技术对流体域网格进行修正;然后流体域将耦合界面处更新后的速度和位移作为初始边界条件进行流场的迭代计算,直至流场结果收敛;最后将流体载荷通过插值施加到结构节点,结构域采用Newton-Raphson方法进行迭代求解得到管道的瞬时位移和速度.流体域和结构域之间多次交换数据,直到满足变量传递收敛准则后,再进行下一个时间步的计算[26].

  • 2 计算模型

  • 2.1 几何模型及物性参数

  • 两相流作用下的水平柔性管道流固耦合模型如图1所示,蓝色表示流体域,灰色表示结构域.其中管道内径D=51mm,壁厚3mm.左端的充分发展段长度L1=4200mm,中部测试段长度L2=1500mm,右端的出口段长度L3=1000mm.空气和水的混合物从管道左侧流入,并在充分发展段中形成特定流型,重力方向沿Z轴负方向.

  • 柔性管道及两种流动介质的物性参数如表1所示.管道入口采用速度入口条件,截面顶部设置为空气入口(红色),底部设置为水入口(蓝色).空气入口和水入口的流速可以表示为:Ul =(Usl·A)/AlUg =(Usg·A)/Ag.其中,UlUg分别表示水和空气的实际流速,A表示管道横截面面积,AlAg分别表示入口处水和空气的实际所占面积,UslUsg分别表示水和空气的折算流速.

  • 图1 柔性管道流固耦合模型

  • Fig.1 Fluid-structure interaction model of the flexible pipe conveying two-phase flow

  • 表1 柔性管道及流体介质物性参数

  • Table1 Physical properties of pipe and fluid

  • 2.2 模型验证

  • 柔性管道采用六面体八节点实体单元进行离散,管道两端施加固支约束条件.流体域通过六面体八节点“O”形网格进行离散,出口采用压力出口条件,两相流直接进入大气;管道壁面采用无滑移边界条件,不考虑壁面接触角对流型的影响;.

  • 为了获得本文数值解受网格疏密程度的影响,首先以气相折算流速和液相折算流速分别为Usg=1.34m/s和Usl=3m/s时的段塞流工况下管内两相流诱导问题为例,对数值模型的网格独立性进行验证,如图2和表2所示.表2中给出了管道中部测点M振动幅值的标准偏差值(dSTD)的对比结果.由表2可知,中等网格和精细网格的数值计算结果偏差小于1%,满足网格收敛性的要求,综合考虑网格数量与计算精度,后文将选用中等网格进行计算,此时结构与流体计算域的网格划分如图3所示.

  • 表2 网格独立性验证

  • Table2 The verification of grid independence

  • 图2 数值计算结果验证

  • Fig.2 The verification of numerical results

  • 图3 计算域网格单元

  • Fig.3 Medium mesh for computational domain

  • 3 结果与分析

  • 3.1 柔性管道固有模态分析

  • 为了更好地分析柔性管道的振动特性,本文建立了空管有限元数值计算模型并对其进行了模态分析.其中,结构采用六面体八节点实体单元进行离散,结构单元数为36000,管道端部单元节点自由度完全约束,求得空管前2阶固有频率为7.1H及7.9Hz.基于声固耦合法建立充水管道流固耦合有限元数值计算模型,分析了管内静水对柔性管道模态特征的影响.其中,采用八节点可压缩无黏声学流体单元对流体进行离散,结构则由六面体八节点实体单元进行离散,流体单元数为264600,结构单元数为36000,管道端部节点自由度完全约束.考虑线性小扰动情况,采用非对称法求得充水管前2阶模态数值解为3.22Hz和8.87Hz.充水管道前2阶模态主要为弯曲模态,振型如图4所示.

  • 图4 仿真所得振型图

  • Fig.4 Numerical results of vibration mode

  • 3.2 柔性管道流致振动分析

  • 图5给出了Usg=1.34m/s和Usl=3m/s时不同时刻管道振动包络图和相应时刻下管内两相流分布云图(红色表示液相,蓝色表示气相).由图可知,气相和液相的密度差异以及气塞和液塞的非均匀分布导致管道弯曲变形程度出现差异,根据柔性管道的变形形状将其振动过程分为两种:一阶振动模态(T=1.22s及T=1.68s)和二阶振动模态(T=1.40s及T=1.52s).一阶振动模态下,液塞(气塞)位于管道中部,气塞(液塞)均匀分布在两侧,振动形状呈现一阶弯曲振型并且主振频率接近一阶固有频率;二阶振动模态下,气塞(液塞)主要分布在管道一侧,管道左右侧弯曲变形出现明显差异,振动形状呈现二阶弯曲振型并且轴向主振频率接近二阶固有频率.气塞和液塞的交替运动及其轴向分布的不对称性导致柔性管道的振动主要由1阶模态为主导且随时间在一阶振动模态和二阶振动模态之间相互切换.

  • 图5 柔性管道瞬时振动包络图及管内流动特征

  • Fig.5 Instantaneous envelope diagram of the pipe and flow characteristics in tube

  • 图6和图7分别给出了Usg=1.34m/s和Usl=3m/s时管道中部测点M沿三个方向的振动位移曲线和压力脉动曲线.由图可知,当液塞进入管道时,液塞密度大且易引起压力脉动升高,导致管道产生冲击振动;当气塞通过时,管道截面平均密度减小且其压力脉动幅值减小,在阻尼的作用下管道振动幅值减小;气塞和液塞的交替运动导致管道振动具有一定的周期性.气塞和液塞沿垂向和轴向的不均匀分布,导致柔性管道的大变形振动主要发生在平面内YZ两个方向,而流体密度沿横向分布较为均匀,其振动主要由小气团的无规则运动诱导产生,因此振动幅值最小.由频域曲线可知,水平柔性管道沿垂向和横向的振动以1阶振动模态为主,而管内气塞和液塞的无规则分布导致柔性管道沿轴向的振动出现了2阶振动模态.

  • 图6 测点M三方向振动位移曲线

  • Fig.6 Vibration responses at point M

  • 图7 压力脉动时域曲线

  • Fig.7 time-histories of pressure fluctuation

  • 图8(a)绘制了不同气相表观流速下柔性管道在YZ两个方向的振动幅值标准差曲线.由图可知,在段塞流区域,管道振动幅值随着气相表观流速的增加而增大并在段塞流-环状流的转变区达到最大值,之后随着气相流量的增大及流型的改变,振幅逐渐减小.为分析不同气相表观流速下的两相流流致振动响应,将柔性管道的主导振动频率和两相流压力脉动频率进行对比,其中fw1表示充水管的一阶固有频率.如图8(b)所示,柔性管道的振动主导频率始终在一阶固有频率附近,说明其主导振动模态为一阶,与图6所示结果一致.当气相表观流速Usg小于1.34m/s时,气液两相流动压力脉动频率较大,最大液塞长度较短,不稳定的压力脉动仍是激发柔性管道振动的主要原因;当1.34m/s<Usg<2.21m/s 时,气液两相流的流动频率与一阶自振频率接近,此时液塞长度逐渐增大,因此柔性管道的振动主要与段塞流动频率及长液塞的通过有关.Usg=2.21m/s的段塞-环状流作用时,段塞流动频率更接近管道的一阶自振频率,且此时最大液塞长度达到最大,导致施加在管壁上的集中作用力较大,使柔性管达到振动最强.Usg>2.21m/s时,气体流量继续增大,液塞变短至溃散消失是导致振动强度逐渐减弱的原因.

  • 图8 不同气相流速下管道振幅及振动频率

  • Fig.8 The STD amplitudes and flow variation in the pipe under different superficial velocities

  • 3.3 柔性管道振动对管内流动的影响

  • 柔性管道的大变形振动会影响管内的流动,图9展示了当Usl=3m/s、Usg=1.34m/s时,相同工况下段塞流通过刚性和柔性管道时液塞长度的变化.如图9(a)所示,刚性管道内的液塞平均长度约为4D,由于液塞在向前运动时其头部会吸收管壁上的液膜,其长度迅速增长至4.6D,液塞增长率为15%.图9(b)中相同长度的液塞受到管道振动的影响,其长度最终稳定在4.2D,液塞增长率仅为5%.这是由于管道的振动变形会使管内的液膜分散,影响液塞前端对液膜的吸收,同时剧烈的振动使液塞尾部不稳定性增强,促使液塞尾部的液体脱落,从而使液塞长度减小.与液塞长度变化相反,柔性管道的变形振动促进了短气塞的相互融合,增加气塞长度.

  • 图9 固定和振动情况下管内段塞流流型的对比

  • Fig.9 Comparison of slug flow in fixed and oscillation pipe

  • 图10 振动对管内段塞流流动的影响

  • Fig.10 The effect of oscillation on the flow characteristics of slug flow

  • 图10(a)进一步分析了Usl=3m/s时,液塞长度随气相表观流速的变化规律并对比了相同工况下管道振动对液塞长度的影响.由图5(a)和图9(a)可知,在段塞流的作用下,柔性管道的振动幅值随气相表观流速的增加而增大,管道的剧烈振动对液膜吸收和液体脱落的影响效果增强,柔性和刚性管道内液塞平均长度差值随气体表观流速的增加而增大.图9(b)展示了不同气相表观流速下管道振动对液塞频率的影响.如图9(b)所示,柔性管道内段塞流的液塞频率高于刚性管道,这与柔性管道中的液塞长度比液塞运动速度减小更明显有关.柔性管道的向下弯曲变形导致管道轴向长度伸长,因此当液塞进入柔性管道后流动速度减缓,而两相流平均流速高达4.34m/s,远高于管道变形速率,因此液塞运动速度与刚性管道内差异较小.综上,柔性管道的振动主要通过改变液塞长度进而影响其流动频率.

  • 对不同气相表观流速下刚性和柔性管道内的压差信号分别进行多尺度熵分析以反映其流动特性变化[27],计算过程中容限r取序列标准差的15%,维数m 取2,最大粗粒化尺度为15,压差数据长度为9000点.图11展示了Usl=3m/s时,气相表观流速Usg分别为1.77m/s和2.21m/s两种工况下管内气液两相流动压差多尺度熵的变化,从压差波动上可以看出,管道的振动使压差时程曲线的微小脉动增加,且压差均值减小,这与管道振动使管内液塞长度和流动速度减小有关.同时发现Usg=1.77m/s时前5个尺度的熵值变化不大,第5个尺度后,振动管道内的压差多尺度熵大于固定管道中的压差多尺度熵,说明虽然管内的流型未发生变化,但振动增加了管内流动的复杂性.当Usg=2.21m/s时,振动情况下的压差多尺度熵大于固定情况的多尺度熵,这与管内流型由段塞流转变为段塞-环状流有关.

  • 图11 刚性和柔性管道内段塞流压差多尺度熵

  • Fig.11 Multi-scale entropy slug flow in rigid pipe and oscillation pipe

  • 4 结论

  • 本文建立了两相流作用下的柔性管道大变形流固耦合模型,研究了不同气相表观流速下段塞流诱导的柔性管道大变形流致振动响应特性,分析了柔性管道的振动模态切换特性及管道的大变形振动对两相流流动特性的影响,研究结果表明:气塞和液塞的交替运动及其轴向分布的不对称性导致柔性管道的振动由1阶模态为主导且随时间在一阶振动模态和二阶振动模态之间相互切换;模态的切换与管内的液塞长度以及气塞和液塞在管内的分布有关,较长的液塞或气塞集中分布在管道中部时易使管道产生一阶模态振动.柔性管道的变形和振动在一定程度上影响了管内两相流的流动.管道的振动变形主要影响液塞和气塞的长度,对液塞的运动速度影响可以忽略.特别是管道的弯曲变形导致液塞尾部液体脱落以及短气塞之间的融合,导致液塞长度进一步减小,进而导致其流动速度减小,流动频率增大,最终影响两相流流型转变的界限(段塞流、与环状流之间).

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  • 参考文献

    • [1] CHENG L X,RIBATSKI G,THOME J R.Two-phase flow patterns and flow-pattern maps:fundamentals and applications [J].Applied Mechanics Reviews,2008,61(5):050802.

    • [2] 席红敏,张伟,姚明辉.变流速输液管的周期和混沌振动 [J].动力学与控制学报,2008,6(3):243-248.XI H M,ZHANG W,YAO M H.Periodic and chaotic vibration of an infusion tube with variable velocity [J].Journal of Dynamics and Control,2008,6(3):243-248.(in Chinese)

    • [3] JAEGER J,SANTOS C M,ROSA L M,et al.Experimental and numerical evaluation of slugs in a vertical air-water flow [J].International Journal of Multiphase Flow,2018,101:152-166.

    • [4] DAUDE F,GALON P A.Finite-Volume approach for compressible single-and two-phase flows in flexible pipelines with fluid-structure interaction [J].Journal of Computational Physics,2018,362:375-408.

    • [5] ORITZ-VIDAL L E,MUREITHI N W,RODRIGUEZ O M H.Vibration response of a pipe subjected to two-phase flow:Analytical formulations and experiments [J].Nuclear Engineering and Design,2017,313:214-224.

    • [6] TAY B L,THORPE R B.Hydrodynamic forces acting on pipe bends in gas-liquid slug flow [J].Chemical Engineering Research and Design,2014,92(5):812-825.

    • [7] GIRAUDEAU M,MUREITHI N W,PETTIGREW M J.Two-phase flow-induced forces on piping in vertical upward flow:Excitation mechanisms and correlation models [J].Journal of Pressure Vessel Technology,2013,135(3):030907.

    • [8] RIVERIN J L,PETTIGREW M J.Vibration excitation forces due to two-phase flow in piping elements [J].Journal of Pressure Vessel Technology,2007,129(1):7-13.

    • [9] WANG L,YANG Y,LIU C,et al.Numerical investigation of dynamic response of a pipeline-riser system caused by severe slugging flow [J].International Journal of Pressure Vessels and Piping,2018,159:15-27.

    • [10] ZHU H J,GAO Y,ZHAO H L.Experimental investigation of slug flow-induced vibration of a flexible riser [J].Ocean Engineering,2019,189:106370.

    • [11] AL-HASHIMY Z I,AL-KAYIEM H H,TIME R W.Experimental investigation on the vibration induced by slug flow in horizontal pipe [J].Journal of Engineering and Applied Sciences,2016,11(20):12134-12139.

    • [12] MA B,SRINIL N.Dynamic characteristics of deep-water risers carrying multiphase flows [C].37th International Conference on Ocean,Offshore & Arctic Engineering,Madrid,2018-06-17-22.

    • [13] MA B,SRINIL N.Planar dynamics of inclined curved flexible riser carrying slug liquid-gas flows [J].Journal of Fluids and Structures,2020,94:102911.

    • [14] JIN G,YAN C,SUN L,et al.Research on frictional resistance of bubbly flow in rolling rectangular ducts [J].Nuclear Engineering and Design,2014,278:108-116.

    • [15] 栾锋,阎昌琪,曹夏昕.摇摆对竖直管内气-水两相流流型的影响分析 [J].工程热物理学报,2007(z1):217-220.LUAN F,YAN Q C,CAO X X.Research for rolling effects upon flow pattern of upward gas-water flow in vertical tubes [J].Journal of Engineering Thermophysics,2007(z1):217-220.(in Chinese)

    • [16] 张金红,阎昌琪,方红宇,等.摇摆对水平管内气液两相流流型的影响 [J].核科学与工程,2007,27(3):206-212.ZHANG J H,YAN Q C,FANG H Y,et al.Effects of rolling on gas-water two-phase flow in horizontal pipes [J].Chinese Journal of Nuclear Science and Engineering,2007,27(3):206-212.(in Chinese)

    • [17] 周云龙,赵盘,杨宁.振动状态下水平管内气液两相流流型转变的实验研究 [J].热能动力工程,2017,32(6):17-22.ZHOU Y L,ZHAO P,YANG N.Experimental study on flow pattern transition of gas liquid two-phase flow in horizontal tubes under vibration condition [J].Journal of Engineering for Thermal Energy and Power,2017,32(6):17-22.(in Chinese)

    • [18] HIBIKI T,ISHII M.Effect of flow-induced vibration on local flow parameters of two-phase flow [J].Nuclear Engineering and Design,1998,185(2-3):113-125.

    • [19] 肖秀,朱庆子,王冠轶,等.振动工况下环管内气液两相流参数分布实验研究 [J].原子能科学技术,2017,51(1):19-26.XIAO X,ZHU Q Z,WANG G Y,et al.Experiment investigation on two-phase flow parameter distribution in annular channel under vibration condition [J].Atomic Energy Science and Technology,2017,51(1):19-26.(in Chinese)

    • [20] 周云龙,常赫.非线性振动下水平通道内气液两相流动研究 [J].原子能科学技术,2019,53(6):1014-1020.ZHOU Y L,CHANG H.Study on gas-liquid two-phase flow in horizontal channel under nonlinear oscillation [J].Atomic Energy Science and Technology,2019,53(6):1014-1020.(in Chinese)

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