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Accuracy Analysis of Ultrasonic Flowmeter for Sewage Based on Fluent DPM Model
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摘要: 针对上游弯管扰乱流场以及污水中颗粒杂质导致超声波衰减问题，基于Fluent Discrete Phase Model（DPM）双向耦合模型进行仿真计算。在污染物浓度为1%情况下，设置4种不同直径的碳酸钙杂质。不同直径杂质的污水中，均出现随着流量点的增大流量系数k值逐渐减小的状况，但在小流量点20 m3/h时，80 μm大颗粒杂质对系数k的影响最大超出了5%，流动速率不足以维持较大的颗粒悬浮在流体中，导致流场中颗粒浓度分布不均，超声波在传播路径上的速度有较大的波动。在压力云图中发现随着颗粒物直径的增加，管道截面上流体速度压力梯度变化较大导致流场波动剧烈，进而影响超声波传播路径上速度的变化，引起流量计产生误差。为了降低大颗粒杂质在下游引起的湍流脉动，在弯角处设置整流器，使用Solidworks建立Laws整流器物理模型。研究发现下游流场更加均匀，速度梯度变化较小，减小了回流涡对超声波在传递路线上的影响。对改善下游流场均匀性，提高超声波流量计在污水中测量精度具有指导意义。Abstract: In order to solve the problem of ultrasonic attenuation caused by the upstream elbow disturbing the flow field and the particle impurities in the sewage, simulation calculations were performed based on the Fluent Discrete Phase Model (DPM) bidirectional coupling model. When the pollutant concentration was 1%, four calcium carbonate impurities of different diameters were set. In the sewage with impurities of different diameters, the flow coefficient k value gradually decreased with the increase of the flow point, but at the small flow point of 20m3/h, the maximum influence of 80 large particle impurities on the coefficient k exceeded 5%, and the flow rate was not enough to keep the larger particles suspended in the fluid, resulting in uneven distribution of particle concentration in the flow field and large fluctuations in the speed of the ultrasonic wave on the propagation path. It was found in the pressure cloud map that with the increase of particle diameter, the fluid velocity pressure gradient on the pipe section changed greatly, resulting in violent fluctuations in the flow field, which in turn affected the change in speed on the ultrasonic wave propagation path and caused errors in the flowmeter. In order to reduce the turbulent pulsation caused by large particle impurities in the downstream, a rectifier was set at the bend, and the Laws rectifier physical model was established using Solidworks. The study found that the downstream flow field was more uniform and the velocity gradient changed less, reducing the influence of the backflow vortex on the ultrasonic wave on the transmission path. It has guiding significance for improving the uniformity of downstream flow field and improving the measurement accuracy of ultrasonic flowmeter in sewage.
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Key words:
- metrology /
- sewage /
- bend pipe /
- ultrasonic flow meter
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图 4 不同颗径下截面流线图
(a)颗粒直径为1 μm. (b)颗粒直径为20 μm. (c)颗粒直径为50 μm. (d)颗粒直径为80 μm
Figure 4. Cross section streamline diagram under different particle sizes
图 5 速度等值云图
(a)颗粒直径为1 μm. (b)颗粒直径为20 μm. (c)颗粒直径为50 μm. (d)颗粒直径为80 μm
Figure 5. Velocity contour cloud map
图 9 流道截面压力分布云图
Figure 9. Cloud diagram of pressure distribution at the cross-section of the channel
表 1 物理参数
Table 1. Physical parameters
Q（m3/h） V(m/s) I(%) Re 20 0.177 4.262 39423 80 0.708 3.584 157692 160 1.415 3.287 315383 400 3.539 2.931 788458 
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[1] L. R. The Theory of Sound[J]. Nature, 1898, 58(1493): 121-122. doi: 10.1038/058121a0 [2] 张全兴. 超声波非均匀介质传播衰减特性研究 [D]. 沈阳: 沈阳工业大学, 2015. [3] HSU C Y, WU S J, WU R M. Particles Separation and Tracks in a Hydrocyclone[J]. Tamkang Institute of Technology Journal, 2011, 14(1): 65-70. [4] Guo S , Xiang N , Li B , et al. Integration method of multipath ultrasonic flowmeter based on velocity distribution[J]. Measurement, 2023, 207: 112388. [5] 张蒙, 杜广生, 程浩, 等. 杂质浓度对超声波传播特性及流量测量精度影响的研究[J]. 中国粮油学报, 2020, 35(10): 176-181. doi: 10.3969/j.issn.1003-0174.2020.10.028 [6] 吕美高. 超声波污水流量测量方法研究与实现 [D]. 抚州: 东华理工大学, 2019. [7] 张宁波. 基于超声衰减的污水悬浊液浓度检测装置研究 [D]. 杭州: 浙江大学, 2016. [8] XU Z, LI M, HAN Y, et al. Robust Flow Estimation Algorithm of Multichannel Ultrasonic Flowmeter Based on Random Sampling Least Squares[J]. Sensors, 2022, 22(19): 7660. doi: 10.3390/s22197660 [9] SAKHAVI N, NOURI N M. Performance of novel multipath ultrasonic phased array flowmeter using Gaussian quadrature integration [J]. Applied acoustics, 2022. [10] GE L, DENG H, WANG Q, et al. Study of the influence of temperature on the measurement accuracy of transit-time ultrasonic flowmeters [J]. Sensor Review, 2019. [11] 马杰, 徐科军, 江圳, 等. 基于超声回波能量峰值点拟合的气体超声波流量计信号处理方法[J]. 计量学报, 2022, 43(5): 597-602. doi: 10.3969/j.issn.1000-1158.2022.05.06 [12] 却依飞, 俞天阳, 张世玮, 等. 超声波峰谷拟合方法及平面叶栅通道二维流速测量[J]. 计量学报, 2023, 44(5): 729-734. doi: 10.3969/j.issn.1000-1158.2023.05.09 [13] 任大呈, 魏华彤, 刘岩, 等. 探头扰流对多声道超声波流量计测量结果影响研究[J]. 仪表技术与传感器, 2023(2): 110-114. doi: 10.3969/j.issn.1002-1841.2023.02.021 [14] 姚爽, 宿彬, 杨宗良, 等. 上游弯管对超声波流量计精度影响及整流设计[J]. 仪器仪表学报, 2022, 43(5): 102-109. [15] CHEN W, WU J, LI C. The Investigation on the Flow Distortion Effect of Header to Guarantee the Measurement Accuracy of the Ultrasonic Gas Flowmeter[J]. Applied Sciences, 2021, 11(8): 3656. doi: 10.3390/app11083656 [16] AMAA , BSHHA, BFMA. Numerical study on the effect of circumferential position of ultrasonic transducers on ultrasonic cross-correlation flowmeter performance under asymmetric air flow profile[J]. Ultrasonics, 2021, 115. [17] CHEN D, CAO H, CUI B. Study on flow field and measurement characteristics of a small-bore ultrasonic gas flow meter[J]. Measurement and Control, 2021, 54(5-6): 554-564. doi: 10.1177/00202940211007515 [18] 吴森林, 王秋良, 但植华, 等. 基于CFD的弯管流动与换热影响因素研究[J]. 中国测试, 2023, 49(9): 7-15. doi: 10.11857/j.issn.1674-5124.2022020102 [19] 石硕. 水中杂质对超声波热量表测量精度影响规律的研究 [D]. 济南: 山东大学, 2017. [20] 霍尔曼. 传热学[M]. 北京: 机械工业出版社, 2005. [21] 刘亚男, 杨鸣. 弯管对超声波流量计测量精度的影响及改善措施[J]. 宁波大学学报(理工版), 2022, 35(3): 98-105. [22] 赵楠楠, 徐安察, 胡亮, 等. 基于声速追踪的超声波液体流量计量方法[J]. 仪表技术与传感器, 2022(9): 41-46. [23] LARIBI B, ABDELLAH HADJ A. Analysis of Turbulent Flow Development Downstream Disturbers with Perforated Plate Flow Conditioner[J]. Applied Mechanics and Materials, 2012, 197: 73-77. doi: 10.4028/www.scientific.net/AMM.197.73 [24] Uhm J H , Romig B W , Chong Y H . FUEL/AIR MIXING SYSTEM FOR FUEL NOZZLE: US201313776638[P]. US2014238025A1[2024-09-30]. [25] 田顺佳, 戚有龙, 冯春辉, 等. 不同整流器对超声波流量计计量的影响[J]. 油气储运, 2021, 40(7): 780-790. doi: 10.6047/j.issn.1000-8241.2021.07.009 [26] PENG S, ZHANG Y, ZHAO W, et al. Analysis of the Influence of Rectifier Blockage on the Metering Performance during Shale Gas Extraction[J]. Energy & Fuels, 2021, 35(1): 03748. [27] 刘桂雄, 陈国宇, 谭文胜. 流量测量流动调整器结构与发展趋势分析[J]. 中国测试, 2020, 46(3): 12-16. doi: 10.11857/j.issn.1674-5124.2019100018 [28] 朱国俊. 典型扰流流场对超声流量计计量性能的影响研究 [D]. 北京: 北京化工大学, 2023. [29] 陈红, 聂西利, 丁渊明. 超声波流量计整流器设计及验证[J]. 自动化仪表, 2018, 39(7): 91-93,102. [30] 邵欣, 王涛, 高芦宝, 等. 基于CFD的超声波气体流量计过渡区内流场检测优化研究[J]. 中国测试, 2021, 47(10): 114-122. doi: 10.11857/j.issn.1674-5124.2021010101 -
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