祖晓萌， 朱曙光

（南京理工大学能源与动力工程学院， 江苏南京210018）

DOI:10.13732/j.issn.1008-5548.2021.02.010

收稿日期： 2020-08-31， 修回日期：2020-09-24，在线出版时间：2020-12-22 15:57。

第一作者简介：祖晓萌(1994—)，女，硕士研究生，研究方向为非均匀气固两相介质衰减特性研究。E-mail：805589879@qq.com。

通信作者简介：朱曙光(1976—)，男，博士，副教授，硕士生导师，研究方向气固两相流测量。E-mail：zhushuguang@tsinghua.org.cn。

摘要：基于蒙特卡罗方法(Monte Carlo method)对超声波在高含量气固两相系统中的传播过程进行理论建模。结果表明:由实验得到40、60、80 k Hz的3种频率条件时体积分数约为63%的玻璃微珠-空气的高含量气固两相系统声衰减随粒径的变化规律曲线;通过改变程序中单次散射能量损失Eloss的取值，将计算结果曲线与实验结果曲线进行拟合，相关系数可达到0.99以上，证明所建立的模型对于超声波透射、散射及其能量损失的处理方法符合其在高含量气固两相系统中的传播规律;在证明模型可行性基础上，进一步计算得到不同粒径颗粒散射衰减随体积分数的增加呈现先增加后减小的变化规律;对于实验所研究的高含量气固两相系统，多次散射过程所导致的散射衰减相对于总的声衰减，可以忽略不计。

关键词：超声衰减；蒙特卡罗方法；气固两相流

Abstract：Based on the Monte Carlo method,the propagation of ultrasonic wave in concentrated gas-solid two-phase flow system was modeled. The results show that the changing law of ultrasonic attenuation coefficients with particle size of high concentration glass beads-air two-phase flow system with volume concentration of 63% at 40,60,and 80 k Hz are obtained by experiment. The correlation coefficient of the simulated result curve with the experimental curve can reach more than 0. 99 by changing the value of Eloss,which proves that the treatment method of ultrasonic transmission,scattering and energy loss is suitable to the propagation law of high concentration gas-solid two-phase system. After the feasibility of the model has been proved,it is further calculated that the scattering attenuation of different particles sizes first increases and then decreases,with the increase of volume concentration. For the high concentration gas-solid two-phase system studied in the experiment,the scattering attenuation caused by multiple scattering process can be ignored compared with the total ultrasonic attenuation.

Keywords：ultrasonic attenuation; Monte Carlo method; gas-solid two-phase flow

参考文献：

[1]李永明, 苏明旭, 袁安利, 等. 基于超声的管道内粉体体积分数的测量[J]. 中国科学院大学学报, 2016, 33(2): 277-282.

[2]RIEBEL U, LÖFFLER F. The fundamentals of particle size analysis by means of ultrasonic spectrometry[J]. Particle & Particle Systems Characterization, 1989, 6(3): 135-143.

[3]ZHENG Y, LIU Q. Review of certain key issues in indirect measurements of the mass flow rate of solids in pneumatic conveying pipelines[J]. Measurement, 2010, 43(6): 727-734.

[4]郭朔. 基于超声法的气固两相流浓度测量研究[D]. 包头： 内蒙古科技大学, 2017.

[5]郭盼盼, 苏明旭, 陈丽, 等. 用蒙特卡罗方法预测液固两相体系中颗粒的超声衰减[J]. 过程工程学报, 2014, 14(4): 562-567.

[6]GU J, FAN F, LI Y, et al. Modeling and prediction of ultrasonic attenuations in liquid-solid dispersions containing mixed particles with Monte Carlo method[J]. Particuology, 2019(2): 84-91.

[7]黄炳发, 苏明旭, 李运思, 等. 基于蒙特卡罗法模拟高含量悬浮物的声衰减[C]//2017年全国声学学术会议论文集， 中国声学学会, 2017: 2.

[8]张帅. 超声波在气固两相介质中的传播模型及特性研究[D]. 南京： 南京理工大学, 2018.

[9]姜根山, 许伟龙, 安连锁. 声波在电站锅炉含颗粒介质气体中的衰减特性[J]. 动力工程学报, 2017, 37(2): 126-133.

[10]EPSTEIN P S, CARHART R R. The absorption of sound in suspensions and emulsions. I. water fog in air[J]. J Acoust Soc Am, 1953, 25(3): 553-565.

[11]ALLEGRA J R. Attenuation of sound in suspensions and emulsions: theory and experiments[J]. The Journal of the Acoustical Society of America, 1972, 51(5): 1545-1564.

[12]CHALLIS R E, POVEY M J W, MATHER M L, et al. Ultrasound techniques for characterizing colloidal dispersions[J]. Reports on Progress in Physics, 2005, 68(7): 1541-1637.

[13]HARKER A H, TEMPLE J A G. Velocity and attenuation of ultrasound in suspensions of particles in fluids[J]. Journal of Physics D: Applied Physics, 2000, 21(11): 1576-1588.

[14]苏明旭, 蔡小舒, 李运思. 一种基于超声衰减谱的混合固体颗粒粒径和浓度的测量方法: 中国, 201510214799.9[P]. 2015-08-19.

[15]张一凡. 能源颗粒细度超声法在线测量研究[D]. 南京： 南京理工大学, 2017.