超声法颗粒两相介质多参数测量

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摘要

在测量颗粒两相流参数的众多技术中，超声法以其无可比拟的优势得到越来越

多研究人员的重视。例如：声波具有较宽的频率范围，可以确保粒径测量范围宽；

声波穿透性能强，适合高浓度，无须稀释的测量；超声测量装置具有非接触特点，

适合在线测量；超声测量系统自动化，智能化程度高，能进行快速实时测量等。

超声法正成为一门快速发展、应用前景广阔的颗粒两相流测量技术。

本文工作围绕超声法颗粒两相介质多参数测量展开。

在介绍两相流和多相流相关概念以及检测技术发展后，简介现有颗粒两相介质

浓度、密度、粘度以及粒度分布的测量技术以及超声测量方法的技术现状。超声

法颗粒两相介质测量中超声特征量包括有声压、声强、声速、声衰减以及声阻抗

等，对颗粒两相介质中声衰减进行了细化，给出了吸收损失、散射损失、粘性损

失、热损失、结构损失以及电声损失的概念。

超声波在颗粒两相介质中的传播效应主要由颗粒相和液体相差异所致，其中包

括有材料取代、压缩性差异、热物性差异以及密度差异等。在超声测粒模型方面，

着重研究了经典的 ECAH 模型和在乳浊液测量中简化的 McClements 模型以及耦合

相Harker&Temple 模型，数值模拟给出了玻璃珠悬浊液和玉米油乳浊液中声衰减

和声相速度随超声频率、颗粒相浓度和粒径的变化关系，最后给出了颗粒两相介

质中粒径测量的反演计算具体过程。

超声颗粒两相介质测量装置由如下组成：超声换能器与信号接收系统、数据采

集系统、计算机数据处理系统以及超声测量区系统。设计的超声测量区又可分为

二种不同类型：直接接触式和反射式脉冲回波式，两者区别在于有无阻抗匹配层。

对于反射式脉冲回波测量装置，分别采用有机玻璃、石英玻璃和不锈钢材料作为

阻抗匹配层，得到了单次和多次超声反射回波信号。

研究超声纵波/横波反射法测量颗粒两相介质浓度、密度、粘度理论和实验，

利用多次回波反射理论，获得了阻抗层和被测介质间反射系数与单一频率上声幅

值和回波次数斜率值的关系，分别对水煤浆、酒精和盐水悬浊液二元溶液的密度

和浓度进行测量。采用横波单次/多次回波反射法测量不同浓度蜂蜜粘度；将横波

法测量结果与旋转式粘度分析仪测量结果进行对比；认为单次横波反射法区分被

测介质和标定物质的横波反射信号较为困难，而横波多次回波反射法能较为精确

计算横波反射系数。

类比声衰减谱测量方法，声相速度谱和阻抗谱也可以建立谱测量的概念。给出

了脂肪乳中声相速度谱测量粒径分布的实例。建立超声测粒模型中声阻抗率谱表

达式，进行理论数值模拟，首次获得了悬浊液和乳浊液中超声阻抗率与超声波频

率，颗粒相浓度和颗粒粒度之间关系，并设计反射式实验装置，从实验上测量得

到声阻抗率谱。相比声衰减谱、声相速度谱的穿透式测量，声阻抗率谱只需处理

被测介质与阻抗层之间的反射关系。

结合超声特征谱方法，以及纵波/横波反射法，设计了集合纵波和横波探头的

测量装置，对不同浓度玉米油乳浊液颗粒两相介质中多个参数：密度、浓度、粘

度和粒径分布同时进行测量。

关键词：超声法颗粒两相介质密度浓度粒径分布粘度声衰减声

速度声阻抗

ABSTRACT

Due to the advantage of real-time, no-invasive, automatic, facile, and reproducible

measurements as well as its adaptability to the on-line measurement and extremely wide

dynamic size range of particles presented in various forms, especially in high

concentration condition, ultrasonic technique as particulate two-phase flow analysis is

given more and more attention , and developed quickly.

This dissertation deals with measurements of multiple parameters in two phase

medium with ultrasonic methods. Multiple parameters include density, concentration,

viscosity and particle size distribution (PSD).

The conception and the measurement technique of two phase flow and multiphase

flow are introduced firstly. Basic introduction about usual density, concentration,

viscosity, PSD measurement techniques and developments and current situation of

ultrasonic technique are discussed in chapter 2. The conceptions of ultrasonic wave in

particulate two phase mixtures are introduced, including acoustic pressure, acoustic

velocity, acoustic impedance, acoustic attenuation, and so on. The acoustic attenuation

can be divided into absorption loss, scattering loss, viscosity loss, thermal loss, structure

loss and electric-acoustic loss.

Ultrasound propagation phenomenon in two phase mixture is outlined as material

substitution, compressibility contrast, thermal contrast and density contrast. In chapter 4,

the developments of ECAH model, McClements model and Harker&Temple (H&T)

coupled-phase model are discussed respectively. The attenuation and velocity in glass

bead and corn oil two phase mixtures are simulated by ECAH, McClements and H&T

models. Inversion technique of particle size measurement is also outlined.

The application system of ultrasonic measuring particulate two phase mixture is

defined as four parts: ultrasonic transducer and signal pulser/receiver system;

high-speed data acquisition system; data processing system; ultrasonic measurement

zone system. Two different measurement zones are also introduced in this chapter.

Using the different materials of buffer rod, we can get the single and multiple echoes.

The concentration and density of coal water slurry, alcohol and NaCl binary

solution are obtained by combining longitudinal acoustic impendence with ultrasonic

longitudinal wave multiple echo reflection method. The honey viscosity is obtained by

transverse acoustic impendence with ultrasonic transverse wave multiple echo reflection

method. It is difficult to distinguish the difference signals between calibration medium

and measured mixture by transverse wave single echo reflection. On the other hand,

ultrasonic transverse wave multiple echo reflection method calculate the transverse

reflection coefficient accurately.

Ultrasonic attenuation, phase velocity, and impendence spectrum are modeled to

characterize the PSD in two phase mixtures. The results of the impendence spectrum

simulated with ECAH, McClements and H&T models are compared with experimental

data from ultrasound reflection application.

At last, combined with the ultrasonic attenuation spectrum method and longitudinal

or transverse wave multiple echo reflection methods, the concentration, density,

viscosity and PSD in corn oil emulsion can be measured.

Key Word：

Ultrasonic method, Particulate two phase mixture, Density,

Concentration, Viscosity, Particle size distribution, Ultrasonic

attenuation, Ultrasonic velocity, Ultrasonic impedance

中文摘要

ABSTRACT

第一章绪论..............................................................................................................1

§1.1 两相流以及多相流相关概念.....................................................................1

§1.2 两相及多相流动检测技术的趋势............................................................3

参考文献................................................................................................................5

第二章颗粒两相介质各参数测试方法综述..........................................................7

§2.1 颗粒两相流参数测试方法综述.................................................................7

§2.1.1 颗粒两相流浓度测量.........................................................................7

§2.1.2 颗粒两相流中密度测量.....................................................................9

§2.1.3 颗粒两相流中粘度测量.....................................................................9

§2.1.4 颗粒粒径测量...................................................................................10

§2.2 超声法颗粒两相流技术发展..................................................................12

§2.3 本文工作...................................................................................................14

参考文献..............................................................................................................16

第三章超声颗粒两相介质测量基本概念............................................................19

§3.1 超声的定义...............................................................................................19

§3.2 声学特征量...............................................................................................19

§3.2.1 声压...................................................................................................19

§3.2.2 声强...................................................................................................20

§3.2.3 声速...................................................................................................20

§3.2.4 声阻抗率...........................................................................................21

§3.2.5 声衰减...............................................................................................22

§3.3 本章小结...................................................................................................24

参考文献..............................................................................................................25

第四章超声法颗粒两相介质测量理论................................................................26

§4.1 超声在颗粒两相介质中的传播...............................................................26

§4.1.1 材料取代..........................................................................................26

§4.1.2 压缩性差异......................................................................................26

§4.1.3 热物性差异......................................................................................27

§4.1.4 密度差异..........................................................................................28

§4.2 超声法颗粒测量理论和物理模型...........................................................28

§4.2.1 ECAH 模型......................................................................................29

§4.2.2 McClements 模型............................................................................ 31

§4.2.3 Harker&Temple 耦合相模型.......................................................... 32

§4.2.4 ECAH 模型、McClements 模型、H&T 模型数值模拟...............35

§4.2.5 反演算法...........................................................................................38

§4.3 本章小结...................................................................................................40

参考文献..............................................................................................................42

第五章实验装置与实验方案................................................................................43

§5.1 超声换能器和信号接收系统...................................................................43

§5.2 数据采集系统...........................................................................................46

§5.3 计算机数据处理系统...............................................................................47

§5.4 超声测量区系统.......................................................................................48

§5.4.1 直接接触式脉冲回波法...................................................................49

§5.4.2 反射式脉冲回波法...........................................................................50

§5.5 本章小结...................................................................................................54

参考文献..............................................................................................................55

第六章纵波/横波反射法测量颗粒两相介质浓度、密度以及粘度..................56

§6.1 纵波多次反射法的理论和应用...............................................................56

§6.1.1 纵波多次回波反射法原理...............................................................56

§6.1.2 纵波多次回波反射法应用...............................................................58

§6.2 横波反射法测量粘度的研究...................................................................60

§6.2.1 横波反射法测量原理.......................................................................61

§6.2.2 横波反射法粘度实验.......................................................................64

§6.3 本章小结..................................................................................................67

参考文献..............................................................................................................68

第七章超声特征量谱测量颗粒两相介质粒径分布............................................69

§7.1 声衰减谱测量颗粒两相介质应用...........................................................69

§7.2 声相速度谱颗粒两相介质理论和应用...................................................70

§7.3 声阻抗率谱测量理论...............................................................................73

§7.3.1 声阻抗率谱与超声测粒模型的关系...............................................73

§7.3.2 声阻抗率谱的数值模拟..................................................................75

§7.3.2.1 纯液体相





和纯颗粒相





的假设................................75

§7.3.2.2 声阻抗率谱与超声频率相互关系..........................................76

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摘要：

摘要在测量颗粒两相流参数的众多技术中，超声法以其无可比拟的优势得到越来越多研究人员的重视。例如：声波具有较宽的频率范围，可以确保粒径测量范围宽；声波穿透性能强，适合高浓度，无须稀释的测量；超声测量装置具有非接触特点，适合在线测量；超声测量系统自动化，智能化程度高，能进行快速实时测量等。超声法正成为一门快速发展、应用前景广阔的颗粒两相流测量技术。本文工作围绕超声法颗粒两相介质多参数测量展开。在介绍两相流和多相流相关概念以及检测技术发展后，简介现有颗粒两相介质浓度、密度、粘度以及粒度分布的测量技术以及超声测量方法的技术现状。超声法颗粒两相介质测量中超声特征量包括有声压、声强、声速、声衰减以及声阻抗...

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