«上一篇
 文章快速检索 高级检索

 应用科技  2019, Vol. 46 Issue (2): 108-115  DOI: 10.11991/yykj.201809012 0

### 引用本文

TANG Huapeng, WEN Jiming, GU Haifeng. Study on image processing technique for bubble volume based on high speed camera[J]. Applied Science and Technology, 2019, 46(2), 108-115. DOI: 10.11991/yykj.201809012.

### 文章历史

1. 中国核动力研究设计院 核反应堆系统设计技术重点实验室，四川 成都 610213;
2. 哈尔滨工程大学 核安全与仿真技术国防重点学科实验室，黑龙江 哈尔滨 150000

Study on image processing technique for bubble volume based on high speed camera
TANG Huapeng1, WEN Jiming2, GU Haifeng2
1. Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institute of China, Chengdu 610213, China;
2. Fundamental Science on Nuclear Safety and Simulation Technology Laboratory, Harbin Engineering University, Harbin 150001, China
Abstract: In order to calculate the volume of bubble with big diameter and severe deformation in bubble column used in filtered containment venting system, this paper introduces four image processing methods for calculating bubble volume, which are equivalent diameter method, ellipsoid volume calculation formulation, horizontal segment method and adaptive segment method, respectively. Analyze the principle and application condition of each method, and calculate bubble volume by these four methods. In the mean time, measure the bubble volume by bubble collecting method. And further, compare the bubble volume calculated by 4 image processing methods and the measured value from experiment, so as to evaluate correctness of the above-mentioned methods. The results show that equivalent diameter method and ellipsoid volume calculation formulation need to use parameters that express integral geometrical feature of the bubble when calculating bubble volume, therefore, when the bubble deforms seriously, the feature parameters changes largely, which will further influence the whole processing precision seriously. Though horizontal segment method possesses excellent performance for calculating ellipsoid bubble, it becomes weak as bubbles' symmetry axis deflects or bubble geometry forms like a disk. Adaptive segment method is the most suitable and high-precision method for highly distorted bubbles, because bubble geometry is recognized according to circularity, and that segment direction is determined by bubble geometry and bubble symmetry.
Keywords: bubble column    bubble volume    image processing    optical method    segment method    adaptive    bubble deformation    experiment

1 实验装置与误差分析 1.1 实验装置

1.2 误差分析

 ${\text{π}} {{{d}}_{{h}}}\sigma = \frac{1}{6}{\text{π}} {d_b}^3{\rho _l}g$ (1)

2 图像处理技术

2.1 图像预处理

2.2 已有处理气泡体积方法评估

 $V = \displaystyle\frac{4}{3}{{\rm{\text{π} }}^{ - \textstyle\frac{1}{2}}}{ A ^{\textstyle\frac{3}{2}}}$ (2)

 $V = \frac{4}{3}{\text{π}} {a^2}b$ (3)

2.3 水平切片法

2.4 自适应切片法

 ${I_a} = {\sum\nolimits_{k = 1}^m {\left( {{L_1} + \varphi {L_2}} \right)} ^2}$ (4)

 $C = \frac{{4{\rm{{\text{π}} }}A}}{{{P_b}^2}}$ (5)

3 不同图像处理方法的实验验证

4 结论

1）当气泡变形较大从而造成气泡形状偏离球形时，气泡在图像上的投影面积会发生改变，使用等效直径法得到的气泡等效直径会发生变化，进而造成等效直径法计算精度的下降。

2）传统的椭球体积计算法因分别选取图像中气泡的水平轴和竖直轴作为长轴和短轴而无法考虑到气泡形状类型发生变化，因此该方法计算结果存在很大的离散性。

3）在气泡上升过程中，其旋转轴发生偏转以及气泡形状的差异，均造成水平切片法的计算精度下降。对椭球型气泡，偏转角度大于27.5°时，误差超过5%；对碟形气泡，误差高达20%以上。

4）在能够准确判断气泡几何形状的基础上，自适应切片法可以根据图像中气泡的对称轴和气泡形状选定合适的切片方向进行图像处理。对于高变形的气泡，自适应切片法具有良好的计算精度和稳健性。

 [1] LEGENDRE D, ZENIT R, VELEZ-CORDERO J R. On the deformation of gas bubbles in liquids[J]. Physics of fluids, 2012, 24(4): 043303. DOI:10.1063/1.4705527 (0) [2] KYRIAKIDES N K, KASTRINAKIS E G, NYCHAS S G, et al. Bubbling from nozzles submerged in water: transitions between bubbling regimes[J]. The Canadian journal of chemical engineering, 1997, 75(4): 684-691. DOI:10.1002/cjce.v75:4 (0) [3] ZHANG Lei, SHOJI M. Aperiodic bubble formation from a submerged orifice[J]. Chemical engineering science, 2001, 56(18): 5371-5381. DOI:10.1016/S0009-2509(01)00241-X (0) [4] AYBERS N M, TAPUCU A. Studies on the drag and shape of gas bubbles rising through a stagnant liquid[J]. Wärme - und stoffübertragung, 1969, 2(3): 171-177. DOI:10.1007/BF00751164 (0) [5] SABERI S, SHAKOURZADEH K, BASTOUL D, et al. Bubble size and velocity measurement in gas-liquid systems: application of fiber optic technique to pilot plant scale[J]. The Canadian journal of chemical engineering, 1995, 73(2): 253-257. DOI:10.1002/cjce.v73:2 (0) [6] DE LASA H, LEE S L P, BERGOUGNOU M A. Bubble measurement in three-phase fluidized beds using a u-shaped optical fiber[J]. The Canadian journal of chemical engineering, 1984, 62(2): 165-169. DOI:10.1002/cjce.v62:2 (0) [7] MARTÍNEZ MERCADO J, CHEHATA GÓMEZ D, VAN GILS D, et al. On bubble clustering and energy spectra in pseudo-turbulence[J]. Journal of fluid mechanics, 2010, 650: 287-306. DOI:10.1017/S0022112009993570 (0) [8] PRASSER H M. Novel experimental measuring techniques required to provide data for CFD validation[J]. Nuclear engineering and design, 2008, 238(3): 744-770. DOI:10.1016/j.nucengdes.2007.02.050 (0) [9] SCHMIDT I, MINCEVA M, ARLT W. Selection of stationary phase particle geometry using X-ray computed tomography and computational fluid dynamics simulations[J]. Journal of chromatography A, 2012, 1225: 141-149. DOI:10.1016/j.chroma.2011.12.072 (0) [10] KULKARNI A A, JOSHI J B, KUMAR V R, et al. Application of multiresolution analysis for simultaneous measurement of gas and liquid velocities and fractional gas hold-up in bubble column using LDA[J]. Chemical engineering science, 2001, 56(17): 5037-5048. DOI:10.1016/S0009-2509(01)00191-9 (0) [11] MAJUMDER S K, KUNDU G, MUKHERJEE D. Bubble size distribution and gas–liquid interfacial area in a modified downflow bubble column[J]. Chemical engineering journal, 2006, 122(1/2): 1-10. (0) [12] HONKANEN M, ELORANTA H, SAARENRINNE P. Digital imaging measurement of dense multiphase flows in industrial processes[J]. Flow measurement and instrumentation, 2010, 21(1): 25-32. DOI:10.1016/j.flowmeasinst.2009.11.001 (0) [13] LECUONA A, SOSA P A, RODRÍGUEZ P A, et al. Volumetric characterization of dispersed two-phase flows by digital image analysis[J]. Measurement science and technology, 2000, 11(8): 1152-1161. DOI:10.1088/0957-0233/11/8/309 (0) [14] MIKAELIAN D, LARCY AÉLIE, DEHAECK S, et al. A new experimental method to analyze the dynamics and the morphology of bubbles in liquids: application to single ellipsoidal bubbles[J]. Chemical engineering science, 2013, 100: 529-538. DOI:10.1016/j.ces.2013.04.013 (0) [15] KESHAVARZI G, PAWELLA R S, BARBER T J, et al. Transient analysis of a single rising bubble used for numerical validation for multiphase flow[J]. Chemical engineering science, 2014, 112: 25-34. DOI:10.1016/j.ces.2014.02.027 (0) [16] HONKANEN M, SAARENRINNE P, STOOR T, et al. Recognition of highly overlapping ellipse-like bubble images[J]. Measurement science and technology, 2005, 16(9): 1760-1770. DOI:10.1088/0957-0233/16/9/007 (0) [17] LAGE L C P, ESPÓSITO R O. Experimental determination of bubble size distributions in bubble columns: prediction of mean bubble diameter and gas hold up[J]. Powder technology, 1999, 101(2): 142-150. DOI:10.1016/S0032-5910(98)00165-X (0) [18] WONGSUCHOTO P, CHARINPANITKUL T, PAVASANT P. Bubble size distribution and gas–liquid mass transfer in airlift contactors[J]. Chemical engineering journal, 2003, 92(1/2/3): 81-90. (0) [19] RAKOCZY R, MASIUK S. Experimental study of bubble size distribution in a liquid column exposed to a rotating magnetic field[J]. Chemical engineering and processing: process intensification, 2009, 48(7): 1229-1240. DOI:10.1016/j.cep.2009.05.001 (0) [20] HANSELMANN W, WINDHAB E. Flow characteristics and modelling of foam generation in a continuous rotor/stator mixer[J]. Journal of food engineering, 1998, 38(4): 393-405. DOI:10.1016/S0260-8774(98)00129-0 (0) [21] AL-OUFI F M, RIELLY C D, CUMMING I W. An experimental study of gas void fraction in dilute alcohol solutions in annular gap bubble columns using a four-point conductivity probe[J]. Chemical engineering science, 2011, 66(23): 5739-5748. DOI:10.1016/j.ces.2011.03.061 (0)