Synchronous Measurement Method of Two-phase Flow Phase Field and Concentration Field Based on Wire-mesh Sensor
-
摘要:
准确认识核反应堆燃料组件内交混行为对其优化设计与安全分析极为关键。丝网传感器可对流道截面进行高时空分辨率相分布成像，结合示踪剂质量平衡法已可实现燃料组件单相交混精细测量。但因缺乏两相下浓度场后处理算法，尚无法应用于两相交混研究。本文考虑到相同空泡份额下液相电导率对丝网敏感体的影响特性，提出了一种两相浓度反演算法，实现了两相流动空泡份额场、液相浓度场同步测量。基于电势场数值模拟与实验确认了算法的正确性与精确度。结果显示算法可适用于各类复杂的两相流工况，典型工况下两相浓度反演算法获得的浓度分布平均相对偏差为3.6%。基于本文实验结果表明，该算法计算获得的浓度矩阵平均相对偏差小于3%，进一步验证了同步测量方法的良好的适用性与精确度。
Abstract:It is crucial to understand the internal mixing behavior accurately of the fuel assemblies in the nuclear reactor which could optimize design and safety analysis. The wire-mesh sensor can measure the flow channel cross-section with high spatial and temporal resolutions. At present, the fine measurement of single-phase mixing based on the wire-mesh sensor combined with the mass balance method has been relatively mature, but it lacks the method of measuring concentration field in the two-phase intersection mixing. Therefore, a two-phase concentration inversion algorithm was proposed in this paper, which could realize the synchronous measurement of the void fraction field and the liquid phase concentration field in the complex flow field. In order to verify the feasibility and accuracy of this algorithm, numerical simulation and experiments were carried out. In calculating the porosity, Maxwell equation was used. COMSOL multiphysics was applied to simulate the gas-liquid two-phase flow field, including simulating the flow field with different concentrations of single bubble and multi-bubble, and adjusting the concentration distribution by changing the conductivity parameters. The simulation method of the wire-mesh sensor was to set two layers of wires as the receiving and emitter of the sensor. The potential of the excited transmitting line was set to 1 V in turn, and the potential of the unexcited transmitting line and the receiving electrode line was set to 0 V respectively. By simulating the single bubble fluid domain, the two-phase concentration inversion algorithm was finally obtained by comparing the candidate algorithms, and the variable concentration field was established in the multi-bubble simulation domain. The simulation results show that the algorithm is suitable for the two-phase mixing precision measurement and has high accuracy. In this paper, the method was verified by the experiment of square tube channel synchronous measurement at normal temperature and pressure. Based on 8×8 wire-mesh sensors, void fraction and concentration distributions could be measured and calculated. The experimental measurement position was located at 0.8 m of the square tube channel, the sampling frequency was 5 000 Hz, and the single sampling time was 20 s. The bubble generator was installed at the bottom of the experimental device to achieve gas-liquid mixing during the experiment. The bubble generator was designed with 12 holes with 1 mm diameter. The gas phase flow range was set to 0.12-0.3 m3/h, and the flow rate was adjusted through the rotary flowmeter. There were four different concentrations of potassium chloride solution. The experimental results show that the peak value of the void fraction is distributed in the center of the square channel and decreases gradually with the approach of the void fraction. It is found that the concentration distribution is relatively uniform and can be accurately measured, which proves the applicability of the synchronous measurement method.
-
-
![]()
图 2 仿真所采用的丝网几何参数及单气泡网格划分
a——丝网几何参数侧视图；b——丝网几何参数俯视图；c——单气泡两相流场网格划分
Figure 2. WMS geometry parameter and meshing of single bubble two-phase flow field used in simulation
![]()
图 3 流体域下无气泡（a）与有单气泡（b）时的电导率分布
Figure 3. Conductivity distribution under fluid domain with no bubble (a) and single bubble (b)
![]()
图 4 流体域下单气泡的时均空泡份额矩阵
Figure 4. Time-averaged void fraction matrix of fluid domain with single bubble
![]()
图 5 0.01 mol/L KCl盐溶液无气泡纯液相与气液两相电导率分布
a——无气泡；b——单气泡
Figure 5. Conductivity distribution of pure liquid without bubble and two-phase of 0.01mol/L KCl salt solution
![]()
图 6 3种算法下0.01 mol/L KCl盐溶液预测的浓度场分布矩阵与实际浓度场分布矩阵
a——实际浓度场分布；b——算法1；c——算法2；d——算法3
Figure 6. Predicted concentration field matrix under three algorithms and theoretical distribution matrix of concentration field of 0.01mol/L KCl salt solution
![]()
图 7 3种算法获得的0.01 mol/L KCl盐溶液预测值与实际值之间的相对偏差
a——算法1；b——算法2；c——算法3
Figure 7. Relative deviation between predicted value and actual value of 0.01 mol/L KCl salt solution calculated by three algorithms
![]()
图 10 流体域下多气泡的时均空泡份额矩阵
Figure 10. Time-averaged void fraction matrix of multi-bubble in fluid domain
![]()
图 11 算法3在变浓度场下的浓度分布对比
a——浓度分布真实值；b——浓度分布预测值；c——相对偏差
Figure 11. Comparative analysis of concentration distribution under variable concentration field of algorithm 3
![]()
图 14 不同气相流量下的时均空泡份额矩阵
气相流量：a——0.12 m3/h；b——0.2 m3/h；c——0.3 m3/h
Figure 14. Time-average void fraction matrix with different gas phase flow rates
![]()
图 15 不同气相流量下计算获得的浓度分布矩阵
气相流量：a——0.12 m3/h；b——0.2 m3/h；c——0.3 m3/h
Figure 15. Calculated concentration distribution matrix for different gas phase flow rates
-
[1] 叶停朴, 吕路路, 张戈, 等. 棒束通道单相和两相交混模型评估[J]. 核动力工程, 2022, 43(2): 47-52. YE Tingpu, LYU Lulu, ZHANG Ge, et al. Evaluation of single-phase and two-phase mixing models for rod bundle channel[J]. Nuclear Power Engineering, 2022, 43(2): 47-52(in Chinese).
[2] 李翔. 带格架棒束通道内冷却剂交混特性及模型研究[D]. 重庆: 重庆大学, 2019. [3] MÖLLER S V. On phenomena of turbulent flow through rod bundles[J]. Experimental Thermal and Fluid Science, 1991, 4(1): 25-35. doi: 10.1016/0894-1777(91)90018-M
[4] LEE C Y, SHIN C H, PARK J Y, et al. An experimental investigation on turbulent flow mixing in a simulated 3×3 dual-cooled annular fuel bundle using particle image velocimetry[J]. Nuclear Engineering and Design, 2013, 260: 134-144. doi: 10.1016/j.nucengdes.2013.03.013
[5] HETSRONI G, LEON J, HAKIM M. Cross flow and mixing of water between semiopen channels[J]. Nuclear Science and Engineering, 1968, 34(2): 189-193. doi: 10.13182/NSE68-A19544
[6] KRAUSS T, MEYER L. Experimental investigation of turbulent transport of momentum and energy in a heated rod bundle[J]. Nuclear Engineering and Design, 1998, 180(3): 185-206. doi: 10.1016/S0029-5493(98)00158-7
[7] GALBRAITH K P. Single phase turbulent mixing between adjacent channels in rod bundles[D]. America: Oregon State University, 1970.
[8] CONBOY T M. Assessment of helical-cruciform fuel rods for high power density LWRS[D]. America: Massachusetts Institute of Technology, 2010.
[9] TOMPKINS C, PRASSER H M, CORRADINI M. Wire-mesh sensors: A review of methods and uncertainty in multiphase flows relative to other measurement techniques[J]. Nuclear Engineering and Design, 2018, 337: 205-220. doi: 10.1016/j.nucengdes.2018.06.005
[10] YLÖNEN A, BISSELS W M, PRASSER H M. Single-phase cross-mixing measurements in a 4×4 rod bundle[J]. Nuclear Engineering and Design, 2011, 241(7): 2484-2493. doi: 10.1016/j.nucengdes.2011.04.014
[11] 张琦, 顾汉洋, 肖瑶, 等. 5×5螺旋十字型棒束组件阻力与交混特性实验研究[J]. 原子能科学技术, 2021, 55(6): 1060-1066. ZHANG Qi, GU Hanyang, XIAO Yao, et al. Experimental study on resistance and mixing characteristics of 5×5 helical cruciform fuel assembly[J]. Atomic Energy Science and Technology, 2021, 55(6): 1060-1066(in Chinese).
[12] RUBIN A S A, AVRAMOVA M. OECD/NRC benchmark based on NUPEC PWR sub-channel and bundle tests (PSBT)[R]. France: OECD, 2012.
[13] SADATOMI M, KAWAHARA A, KANO K, et al. Single- and two-phase turbulent mixing rate between adjacent subchannels in a vertical 2×3 rod array channel[J]. International Journal of Multiphase Flow, 2004, 30(5): 481-498. doi: 10.1016/j.ijmultiphaseflow.2004.03.001
[14] PRASSER H M, SCHOLZ D, ZIPPE C. Bubble size measurement using wire-mesh sensors[J]. Flow Measurement and Instrumentation, 2001, 12(4): 299-312. doi: 10.1016/S0955-5986(00)00046-7
[15] PRASSER H M. Evolution of interfacial area concentration in a vertical air-water flow measured by wire-mesh sensors[J]. Nuclear Engineering and Design, 2007, 237(15/16/17): 1608-1617.
[16] DAVE A J, MANERA A, BEYER M, et al. Uncertainty analysis of an interfacial area reconstruction algorithm and its application to two group interfacial area transport equation validation[J]. Nuclear Engineering and Design, 2016, 310: 620-637. doi: 10.1016/j.nucengdes.2016.10.038
[17] PRASSER H M, BÖTTGER A, ZSCHAU J. A new electrode-mesh tomograph for gas-liquid flows[J]. Flow Measurement and Instrumentation, 1998, 9(2): 111-119. doi: 10.1016/S0955-5986(98)00015-6
[18] PRASSER H M, HÄFELI R. Signal response of wire-mesh sensors to an idealized bubbly flow[J]. Nuclear Engineering and Design, 2018, 336: 3-14. doi: 10.1016/j.nucengdes.2017.04.016
下载:
计量
- 文章访问数: 30
- HTML全文浏览量: 4
- PDF下载量: 28
