﻿ 光学互相关测速系统设计与验证
 光学仪器  2020, Vol. 42 Issue (2): 75-79 PDF

1. 上海理工大学 上海市动力工程多相流动与传热重点实验室，上海 200093;
2. 上海航天动力技术研究所，上海 201109

Design and experimental validation of velocity measurement system based on optical cross correlation method
SHI Zhixiong1, PAN Kewei2, YANG Yifan1, YANG Bin1, WANG Zhanping1, LIU Jinliang1
1. Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China;
2. Shanghai Space Propulsion Technology Research Institute, Shanghai 201109, China
Abstract: Aiming at the measurement of the moving velocity of two-phase flow particles, a dual-path laser velocimetry experimental system was designed based on the principle of cross correlation, and an optical cross correlation velocimetry experiment was carried out by using a known rotating linear velocity device driven by a variable frequency motor. By measuring the intensity signal of the dual-path lasers around the rotating wire, rotation line velocity of wire at the measured point was calculated by the cross correlation analysis of the two intensity signals of the dual-path lasers. Compared with the calculated line velocities of wire at the measured point by using the rotate speed of motor, the relative deviations were less than 6%, verifying the accuracy of optical mutual light velocimetry.
Key words: online measurement    correlation velocity measurement method    optical cross correlation method    two phase flow    measurement error

1 光学互相关法测速原理

 图 1 光学互相关测速原理示意图 Figure 1 Schematic of velocity measurement based on optical cross correlation method

 $\ln \left( {\frac{I}{{{I_0}}}} \right) = - \frac{{\rm{\pi }}}{4}LN{D^2}E\left( {\lambda ,m,D} \right)$ (1)

 ${R_{12}}\left( \tau \right) = \mathop {\lim }\limits_{T \to \infty } \frac{1}{T}\int_0^t {{y_1}} \left( {t - \tau } \right){y_2}\left( t \right){\rm{d}}t$ (2)

 $v = {l/{{\tau _0}}}$ (3)

 $\overline x {\rm{ = }}\frac{1}{n}\sum\limits_{i = 1}^n {{x_i}}$ (4)

X的实验标准偏差可用贝塞尔公式计算得到，即

 $\sigma {\rm{ = }}\sqrt {\frac{1}{\nu }\sum\limits_{i = 1}^n {{{\left( {{x_i} - \bar x} \right)}^2}} }$ (5)

 ${\sigma _{\overline x }} = \frac{\sigma }{{\sqrt n }}$ (6)

 $U = k \cdot \mu$ (7)

2 光学互相关测速系统

 图 2 光学互相关测速实验系统 Figure 2 Experimental system of velocity measurement based on optical cross correlation method
3 测量结果与分析 3.1 典型信号的互相关分析

 图 3 典型探测器光强信号 Figure 3 Typical light intensities of detectors

 图 4 典型光强信号的互相关分析结果 Figure 4 Cross correlation coefficient of typical light intensities
3.2 测量不确定度评定

3.3 测量误差分析

4 结　论

 [1] 李海青. 两相流参数检测及应用[M]. 杭州: 浙江大学出版社, 1991. [2] 李海青, 黄志尧. 特种检测技术及应用[M]. 杭州: 浙江大学出版社, 2000. [3] IBSEN C H, SOLBERG T, HJERTAGER B H, et al. Laser Doppler anemometry measurements in a circulating fluidized bed of metal particles[J]. Experimental Thermal and Fluid Science, 2002, 26(6/7): 851–859. [4] LIU X H, GAO S Q, LI J H. Characterizing particle clustering behavior by PDPA measurement for dilute gas–solid flow[J]. Chemical Engineering Journal, 2005, 108(3): 193–202. DOI:10.1016/j.cej.2005.01.012 [5] 阮晓东, 刘志皓, 瞿建武. 粒子图像测速技术在两相流测量中的应用研究[J]. 浙江大学学报(工学版), 2005, 39(6): 785–788. DOI:10.3785/j.issn.1008-973X.2005.06.006 [6] 王池, 王自和, 张宝珠, 等. 流量测量技术全书[M]. 北京: 化学工业出版社, 2012. [7] 徐苓安. 相关流量测量技术[M]. 天津: 天津大学出版社, 1998. [8] 蒋泰毅, 熊友辉. 气固两相流速度及质量流量的静电测量法研究[J]. 华中科技大学学报(自然科学版), 2005, 33(1): 93–95. DOI:10.3321/j.issn:1671-4512.2005.01.031 [9] 赵安, 韩云峰, 翟路生, 等. 气液两相流电容传感器相浓度测量特性[J]. 化工学报, 2015, 66(7): 2402–2410. DOI:10.11949/j.issn.0438-1157.20150166 [10] 柴继河. 超声相关流量计的设计[D]. 西安: 西安理工大学, 2004. [11] 周洁, 袁镇福, 岑可法, 等. 光信号互相关测量两相流中颗粒流动速度的研究[J]. 中国电机工程学报, 2003, 23(1): 185–188. DOI:10.3321/j.issn:0258-8013.2003.01.040 [12] 蔡小舒, 苏明旭, 沈建琪. 颗粒粒度测量技术及应用[M]. 北京: 化学工业出版社, 2010. [13] CAI X S, LI J F, OUYANG X, et al. In-line measurement of pneumatically conveyed particles by a light transmission fluctuation method[J]. Flow Measurement and Instrumentation, 2005, 16(5): 315–320. DOI:10.1016/j.flowmeasinst.2005.03.011 [14] 倪育才. 实用测量不确定度评定[M]. 5版. 北京: 中国质检出版社, 中国标准出版社, 2016.