管间两相流场频域相关性及激振力功率谱密度研究  

Frequency Domain Correlation of Two-Phase Flow Field and Power Spectral Density of Excitation Force Inside the Tube Bundle

作　　者：朱国瑞[1,2,3] 蔺文静 齐思久 韩佩泽 谭蔚 Zhu Guorui;Lin Wenjing;Qi Sijiu;Han Peize;Tan Wei(School of Chemical Engineering and Technology,Tianjin University,Tianjin 300350,China;Zhejiang Institute of Tianjin University,Ningbo 315000,China;Haihe Laboratory of Sustainable Chemical Transformations,Tianjin 300192,China)

机构地区：[1]天津大学化工学院,天津300350 [2]天津大学浙江研究院,宁波315000 [3]物质绿色创造与制造海河实验室,天津300192

出　　处：《天津大学学报(自然科学与工程技术版)》2025年第4期423-433,共11页Journal of Tianjin University:Science and Technology

基　　金：中央装备发展部预研课题(32102040601).

摘　　要：管壳式换热器内部管束长期受到气-水两相流冲刷容易发生磨损破坏,影响其使用寿命,因此准确计算两相流体力的功率谱密度对管束的磨损计算至关重要.由于缺乏两相流条件下的管间流场相关性实验数据,难以用激振力去直接计算其等效功率谱密度.为了探究管间两相流流场相关性,给出可靠的两相流激振力包络谱,设计搭建了两相水洞实验装置,创新性地将电子压力扫描阀引入两相流环境中,直接测量管表面的压力.对节径比为1.41的正三角形刚性管阵中单根弹性管在环境温度和压力下的横向流致振动进行了全面的实验研究.研究了直径为0.026 m、长度为0.237 m的柔性管在10%~90%含气率下激振力的频域特征并计算了相关长度,通过分析压力的变化、激振力自相关功率谱密度以及斯特劳哈尔数确定了周期性漩涡脱落现象的出现,获得了不同含气率下基于界面流速的激振力无量纲参考等效功率谱密度.结果表明,压力随界面流速大致呈抛物线形式增加,但涡流脱落会导致管周的压力骤降;管束内部激振力的相干函数在大范围内数值较低,相关长度不到1倍管径.使用1倍管径为相关长度计算了3种不同结构参数弹性管的激振力等效功率谱密度,采用基于界面流速的归一化因子进行了无量纲处理,给出了10%~30%含气率、40%~60%含气率以及70%~90%含气率时的激振力包络谱,其中激振力在40%~60%含气率下能量最高,70%~90%含气率次之,10%~30%含气率下能量最低.研究结果给壳程不同位置管束的磨损计算提供了符合工程实践的载荷谱.The inner tube bundle of shell and tube heat exchangers often suffers from wear and damage owing to prolonged exposure to gas-water two-phase flow,which compromises their service life.Therefore,accurately calculating the power spectral density of two-phase flow force is crucial for wear calculation of tube bundle.The lack of experimental data on flow field correlations inside the tube bundle under two-phase flow conditions makes it challenging to directly calculate the equivalent power spectral density alongside the excitation force.To investigate the correlation of the two-phase flow field and develop a reliable envelope spectrum for the excitation force of the two-phase flow,a two-phase water tunnel experimental device was designed and built.This setup incorporated an innovative electronic pressure scanning system,which was introduced into the two-phase flow environment to directly measure pressure on the tube surfaces.The study focused on the transverse flow-induced vibration of a single elastic tube in a normal triangular rigid tube array featuring a pitch-to-diameter ratio of 1.41 under ambient temperature and pressure.We examined the frequency domain characteristics of the exciting force on a flexible tube measuring 0.026 m in diameter and 0.237 m in length across a void fraction range of 10%to 90%and calculated the correlation length.Periodic vortex shedding was determined by analyzing the change in pressure,the autocorrelation power spectral density of the excitation force,and the Strouhal number.The dimensionless reference equivalent power spectral density of the excitation force,calculated based on the interface’s flow rate under different void fractions,was determined.The results reveal that pressure tends to increase in a parabolic form with interface flow rate,but vortex shedding can cause significant pressure drops around the tube.The coherence function of the excitation force inside the bundle is low across a wide frequency range,with the correlation length measuring less than the tube diameter.U

关 键 词：管壳式换热器 管束 两相流 激振力 功率谱密度 

分 类 号：TK172[动力工程及工程热物理—热能工程]