Mathematical Model of Fog Flow Source Strength and Diffusion in Flood Discharge Atomization

HE Gui-cheng; ZHANG Hua; PENG Yan-xiang

doi:10.11988/ckyyb.20230561

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Journal of Changjiang River Scientific Research Institute ›› 2024, Vol. 41 ›› Issue (11) : 109-117. DOI: 10.11988/ckyyb.20230561

Hydraulics

Mathematical Model of Fog Flow Source Strength and Diffusion in Flood Discharge Atomization

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Abstract

In the process of flood discharge atomization, a large number of water droplets will be generated by the collision between the jetted water tongue and the downstream water cushion pond. The droplets carried by the airflow form a fog flow, which affects slope stability and traffic safety. To predict the distribution of fog flow in the downstream space, the interaction process between the jetted water tongue, air, and downstream water was simulated, and a background field for fog flow generation and transport was constructed. Based on the fog source generation mechanism and dimensional analysis methods, a calculation formula for fog flow source strength is proposed, and a mathematical model for fog flow source strength and diffusion is established. The fog flow process of the 3^# spillway hole discharge at the Manwan hydropower station is simulated using this model. The comparison shows that the distribution of fog flow source strength and the location of the fog source generation are consistent with prototype observation. The distribution of fog flow concentration distribution in the downstream space is in line with the prototype observation, and the calculated values of fog flow concentration at observation points match the trend of the original observed values. The comparison results verify the applicability of this model, providing a new method for predicting the distribution of fog flow in downstream spaces of flood discharge atomization.

Key words

flood discharge atomization / fog flow concentration / fog flow source strength / fog flow diffusion / Manwan hydropower station

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HE Gui-cheng , ZHANG Hua , PENG Yan-xiang. Mathematical Model of Fog Flow Source Strength and Diffusion in Flood Discharge Atomization[J]. Journal of Yangtze River Scientific Research Institute. 2024, 41(11): 109-117 https://doi.org/10.11988/ckyyb.20230561

References

List( Publishing order | Descend order by publishing year | Descend order by cited within ) Chart analysis

[1]	刘宣烈, 刘钧. 三元空中水舌掺气扩散的试验研究[J]. 水利学报, 1989, 20(11): 10-17. (LIU Xuan-lie, LIU Jun. Experimental Study on the Diffusion and Aeration of Three-dimensional Jet[J]. Journal of Hydraulic Engineering, 1989, 20(11): 10-17. (in Chinese)) Cited in this article [1]

[2]

王思莹, 王才欢, 陈端. 泄洪雾化研究进展综述[J]. 长江科学院院报, 2013, 30(7): 53-58, 63.

https://doi.org/10.3969/j.issn.1001-5485.2013.07.011

Abstract

高坝工程泄洪形成的泄洪雾化现象对水利枢纽的正常运行、交通安全、周围环境甚至下游岸坡稳定均可能造成危害。通过全面细致的文献调研,对我国泄洪雾化相关的研究进展进行了归纳总结,梳理了对泄洪雾化危害的认识过程,总结了对泄洪雾化形成过程的逐步了解,对比了不同模型试验和数值分析的研究成果。在对当前研究现状的认识基础上,指出今后泄洪雾化相关研究工作的开展应该注重测量技术的改进,以获得更详尽的原型和模型观测资料。此外,对泄洪雾化雾源特性的研究是今后研究的一个重要方向。

(WANG

Si-ying

, WANG

Cai-huan

, CHEN

Duan

. Advances in Research on Flood Discharge Atomization[J]. Journal of Yangtze River Scientific Research Institute, 2013, 30(7): 53-58, 63. (in Chinese))

https://doi.org/10.3969/j.issn.1001-5485.2013.07.011

Cited in this article [1] Abstract

<p>Flood discharge atomization of high dam projects will have possible negative impact on the hydropower station operation, traffic safety, surrounding environment, and even the stability of the downstream bank slope. Researchers have done much work in this regard, and meanwhile there is still much work to do because of its significance and complexity. This paper presents a full scale review on current study on this issue, summarizes the cognition on its damage, the forming mechanism of the atomization, and the comparison of different experimental and numerical research results. It’s proposed that two aspects should be focused on in the future study: first, advanced measuring equipment and methods should be imported and invented to obtain more particular and accurate information; second, properties of the atomization source should be paid more attention to.</p>

[3]

王劲, 罗玉龙, 殷亮, 等. 某水电站左岸边坡泄洪雾化防护措施比选[J]. 河海大学学报(自然科学版), 2014, 42(6): 553-558.

(WANG

Jin

, LUO

Yu-long

, YIN

Liang

, et al. Comparison and Selection of Protection Schemes for Left-bank Slope at a Hydropower Station during Flood Discharge Atomization[J]. Journal of Hohai University (Natural Sciences), 2014, 42(6):553-558. (in Chinese))

Cited in this article [1]

[4]	练继建, 何军龄, 缑文娟, 等. 泄洪雾化危害的治理方案研究[J]. 水力发电学报, 2019, 38(11): 9-19. (LIAN Ji-jian, HE Jun-ling, GOU Wen-juan, et al. Study on Harnessing Schemes of Flood Discharge Atomization[J]. Journal of Hydroelectric Engineering, 2019, 38(11): 9-19. (in Chinese)) Cited in this article [1]

[5]	孙时元, 童显武, 苏祥林, 等. 东江水电站滑雪式溢洪道水力学原型观测[J]. 水力发电, 1994, 20(1): 6-11. (SUN Shi-yuan, TONG Xian-wu, SU Xiang-lin, et al. Hydraulic Prototype Observation of Ski Spillway of Dongjiang Hydropower Station[J]. Water Power, 1994, 20(1): 6-11. (in Chinese)) Cited in this article [1]

[6]

杨朝晖, 吴守荣, 刘善均, 等. 宝珠寺水电站泄洪雾化原型观测[J]. 水利水电技术, 2007, 38(1):69-73.

(YANG

Zhao-hui

, WU

Shou-rong

, LIU

Shan-jun

, et al. Prototype Observation of Discharge Atomization at Baozhusi Hydropower Station[J]. Water Resources and Hydropower Engineering, 2007, 38(1):69-73. (in Chinese))

Cited in this article [1]

[7]

杜兰, 卢金龙, 李利, 等. 大型水利枢纽泄洪雾化原型观测研究[J]. 长江科学院院报, 2017, 34(8): 59-63.

https://doi.org/10.11988/ckyyb.20160455

Abstract

大型水利枢纽,尤其采用挑流消能工的高坝工程,在泄洪时产生的雾化降雨强度远超自然降雨,由此对枢纽正常运行、泄洪区交通安全、周围环境等均构成危害。对金沙江下游溪洛渡水电站大坝深孔泄洪时雾化影响范围、降雨强度分布、气象特性等进行了重点观测研究。结果表明:溪洛渡水电站深孔泄洪雾化降雨强度分布呈现局部降雨强度大、降雨强度沿纵向及岸坡方向递减速度快的特点;观测工况下最大降雨强度达4 704 mm/h;观测时段自然风速未超过3.5 m/s条件下,泄洪区最大风速达16.3 m/s;自然气压为0 kPa、空气湿度为85%左右时,最大气压约为96 kPa,空气湿度为100%。观测成果一方面可对溪洛渡水电站岸坡防护设计进行验证,并为以后类似工程的岸坡防护设计提供参考,另一方面可为其他研究手段的完善提供丰富详实数据,具有重要价值。

(DU

Lan

, LU

Jin-long

, LI

, et al. Prototype Observation on Flood Discharge Atomization of Large Hydraulic Project[J]. Journal of Yangtze River Scientific Research Institute, 2017, 34(8): 59-63. (in Chinese))

https://doi.org/10.11988/ckyyb.20160455

Cited in this article [1] Abstract

The atomization rainfall induced by flood discharge of large hydraulic projects, especially those with ski-jump energy dissipater, is far more intense than natural rainfall, harmful for the project's normal operation, traffic safety, and surrounding environment. In this article, prototype observation is carried out to research the atomization influence scope, rainfall intensity distribution, and meteorological characteristics during the deep-hole discharge of Xiluodu hydraulic project in the downstream of Jinsha River. Results suggest that distributing in some local positions, the atomization rainfall intensity at Xiluodu hydropower project decreases rapidly along longitudinal and bank slope directions. In observation condition, the maximum intensity reaches 4 704 mm/h; when natural wind speed is smaller than 3.5 m/s, the maximum wind speed in flood discharge area is up to 16.3 m/s; and when natural air pressure and humidity are 0 kPa and 85% respectively, the maximum air pressure and humidity in flood discharge area reaches 96 kPa and 100%,respectively. The observation results could be used to verify the design of bank slope protection for Xiluodu hydropower project, and also provides rich and detailed data for other research approaches.

[8]

刘宣烈, 安刚, 姚仲达. 泄洪雾化机理和影响范围的探讨[J]. 天津大学学报, 1991, 24(增刊1): 30-36.

(LIU

Xuan-lie

, AN

Gang

, YAO

Zhong-da

. The Investination on the Mechanism and Sphere of Influence of Atomization by Discharge Flow[J]. Journal of Tianjin University (Science and Technology), 1991, 24(Supp. 1): 30-36. (in Chinese))

Cited in this article [1]

[9]

梁在潮. 雾化水流溅水区的分析和计算[J]. 长江科学院院报, 1996, 13(1): 9-13.

Abstract

分析了雾化水流溅水区的特性和建立了溅水影响范围的计算公式。内容包括: (1) 溅水现象和溅水水滴的反弹特性分析; (2) 溅水水滴抛射运动轨迹的计算; (3) 溅水影响范围的计算; (4) 模型试验的验证。主要结论: (1) 建筑物尽可能避免放置在溅水区内; (2) 溅水区的估算建议用考虑水舌风影响的溅水水滴溅抛运动方程计算。

(LIANG

Zai-chao

. Analysis and Calculation of Splash Area of Atomized Water Flow[J]. Journal of Yangtze River Scientific Research Institute, 1996, 13(1): 9-13. (in Chinese))

Cited in this article [1] Abstract

[10]	梁在潮, 刘士和, 胡敏良, 等. 小湾水电站泄流雾化水流深化研究[J]. 云南水力发电, 2000, 16(2): 28-32. (LIANG Zai-chao, LIU Shi-he, HU Min-liang, et al. Study in a Deepgoing Way of Water Discharge Atomized Flow for Xiaowan Hydropower Project[J]. Yunnan Water Power, 2000, 16(2): 28-32. (in Chinese)) Cited in this article [1]

[11]	梁在潮. 雾化水流计算模式[J]. 水动力学研究与进展(A辑), 1992, 7(3): 247-255. (LIANG Zai-chao. A Computation Model for Atomization Flow[J]. Journal of Hydrodynamics, 1992, 7(3): 247-255. (in Chinese)) Cited in this article [1]

[12]	KUIPERS J A M, VAN DUIN K J, VAN BECKUM F P H, et al. Computer Simulation of the Hydrodynamics of a Two-dimensional Gas-fluidized Bed[J]. Computers & Chemical Engineering, 1993, 17(8): 839-858. Cited in this article [1]

[13]

张华, 练继建. 应用水滴随机喷溅数学模型预测挑流泄洪雾化的雨强分布[J]. 三峡大学学报(自然科学版), 2004, 26(3): 210-213.

(ZHANG

Hua

, LIAN

Ji-jian

. Application of Mathematic Model of Water Drops Random Spattering to Prediction of Rainfall Intensity Distribution in Deflecting Flood Release and Atomization[J]. Journal of China Three Gorges University(Natural Sciences), 2004, 26(3): 210-213. (in Chinese))

Cited in this article [1]

[14]

张华, 何贵成. 泄洪雾化水滴分档随机喷溅数学模型及其验证[J]. 水利水电科技进展, 2022, 42(1): 53-60.

(ZHANG

Hua

, HE

Gui-cheng

. Mathematical Model of Graded Random Splashing Droplets in Flood Discharge Atomization and Its Verification[J]. Advances in Science and Technology of Water Resources, 2022, 42(1): 53-60. (in Chinese))

Cited in this article [1]

[15]	柳海涛, 孙双科, 郑铁刚, 等. 两河口水电站泄洪雾化影响分析[J]. 水力发电, 2016, 42(11): 54-57. (LIU Hai-tao, SUN Shuang-ke, ZHENG Tie-gang, et al. Analysis of Flood Discharge Atomization in Lianghekou Hydropower Station[J]. Water Power, 2016, 42(11): 54-57. (in Chinese)) Cited in this article [1]

[16]	刘之平, 柳海涛, 孙双科. 大型水电站泄洪雾化计算分析[J]. 水力发电学报, 2014, 33(2): 111-115. (LIU Zhi-ping, LIU Hai-tao, SUN Shuang-ke. Computational Analysis of Flood Discharging Atomization of Large Hydropower Engineering[J]. Journal of Hydroelectric Engineering, 2014, 33(2): 111-115. (in Chinese)) Cited in this article [1]

[17]

齐春风, 练继建, 刘昉, 等. 玛尔挡水电站泄洪雾化数学模型研究[J]. 水利水电技术, 2017, 48(12): 106-110, 194.

(QI

Chun-feng

, LIAN

Ji-jian

, LIU

Fang

, et al. Study on Mathematical Model of Flood Discharge Atomization for Maerdang Hydropower Station[J]. Water Resources and Hydropower Engineering, 2017, 48(12): 106-110, 194. (in Chinese))

Cited in this article [1]

[18]	LIU S H, SUN X F, LUO J. Unified Model for Splash Droplets and Suspended Mist of Atomized Flow[J]. Journal of Hydrodynamics, 2008, 20(1): 125-130. Cited in this article [1]

[19]	LIU S H, YIN S R, LUO Q S, et al. Numerical Simulation of Atomized Flow Diffusion in Deep and Narrow Goeges[J]. Journal of Hydrodynamics, 2006, 18(1): 504-507. Cited in this article [2]

[20]	刘刚. 基于水气两相流理论的高坝泄洪雾化计算研究[D]. 宜昌: 三峡大学, 2020. LIU Gang. Research on Numerical Calculation of Flood Discharge Atomization of High Dam Based on Water-air Two-phase Flow[D]. Yichang: China Three Gorges University, 2020. (in Chinese)) Cited in this article [2]

[21]	HIRT C W, NICHOLS B D. Volume of Fluid (VOF) Method for the Dynamics of Free Boundaries[J]. Journal of Computational Physics, 1981, 39(1): 201-225. Cited in this article [1]

[22]	MÁRQUEZ D S. An Extended Mixture Model for the Simultaneous Treatment of Short and Long Scale Interfaces[D]. Santa Fe: Universidad Nacional Del Litoral, 2013. Cited in this article [1]

[23]	SAEEDIPOUR M, PIRKER S, BOZORGI S, et al. An Eulerian-Lagrangian Hybrid Model for the Coarse-grid Simulation of Turbulent Liquid Jet Breakup[J]. International Journal of Multiphase Flow, 2016, 82: 17-26. Cited in this article [3]

[24]	RAYLEIGH L. On the Instability of Jets[J]. Proceedings of The London Mathematical Society, 1878, 1(1):4-13. Cited in this article [2]

[25]	WEBER C. On the Disintegration of a Liquid Jet[J]. Zamm-zeitschrift Fur Angewandte Mathematik Und Mechanik, 1931, 11(2): 136-154. Cited in this article [2]

[26]	OHNESORGE W. The Formation of Drops by Nozzles and the Breakup of Liquid Jets[J]. Zeitschrift für Angewandte Mathematik und Mechanik, 1936, 16 (6): 355-358. Cited in this article [2]

[27]	LIN S P, REITZ R D. Drop and Spray Formationfrom a Liquid Jet[J]. Annual Review of Fluid Mechanics, 1998, 30: 85-105. Cited in this article [2]

[28]	ISSA R I, AHMADI-BEFRUI B, BESHAY K R, et al. Solution of the Implicitly Discretised Reacting Flow Equations by Operator-splitting[J]. Journal of Computational Physics, 1991, 93(2): 388-410. Cited in this article [1]

[29]	PATANKAR S V, SPALDING D B. A Calculation Procedure for Heat, Mass and Momentum Transfer in Three-dimensional Parabolic Flows[J]. International Journal of Heat and Mass Transfer, 1972, 15(10): 1787-1806. Cited in this article [1]

[30]	傅树红, 黄伟. 漫湾水电站枢纽布置[J]. 水力发电, 1993, 19(6): 25-28, 71. (FU Shu-hong, HUANG Wei. General Layout of Manwan Hydropower Station[J]. Water Power, 1993, 19(6): 25-28, 71. (in Chinese)) Cited in this article [1]

[31]	吴福生, 程和森. 漫湾水电站泄流雾化原型观测研究[J]. 云南水力发电, 1998, 14(3): 9-14, 23. (WU Fu-sheng, CHENG He-sen. Prototype Observation and Study of Flood Discharge-caused Atomization at Manwan Hydropower Station[J]. Yunnan Water Power, 1998, 14(3): 9-14, 23. (in Chinese)) Cited in this article [3]

[32]

王思莹, 刘向北, 陈端. 挑流水舌泄洪雾化源形成过程研究[J]. 长江科学院院报, 2015, 32(2): 53-57.

https://doi.org/10.3969/j.issn.1001-5485.2015.02.012

Abstract

水利工程大功率泄洪引发的强降雨及雾流对工程运行安全和周围生态环境均可能产生较大影响。以往研究工作主要从工程安全出发,关注大坝下游两岸岸坡的泄洪雾化影响范围和雨强分布特性。由于泄洪雾化涉及复杂的水气两相流和高速水流运动问题,现阶段对雾化形成机理的研究尚不透彻。通过概化模型试验,利用高速摄影等测量手段,对不同水力条件下挑流水舌落水产生泄洪雾化的过程进行了观测分析,重点研究了落水点附近表面水体激溅反弹产生雾化源的过程,分析了泄洪雾化主要雾化源的组成和特点。研究表明泄洪雾化主要由水舌空中紊动掺气形成的抛洒雾源和水舌与下游水体碰撞反弹形成的激溅雾源组成,特别指出激溅雾源的形成与水舌入水导致的下游水体表面周期性壅水形成、破裂、消落的过程密切相关。

(WANG

Si-ying

, LIU

Xiang-bei

, CHEN

Duan

. Formation of Atomization Source Caused by Flood Discharge Flow Nappe[J]. Journal of Yangtze River Scientific Research Institute, 2015, 32(2): 53-57. (in Chinese))

https://doi.org/10.3969/j.issn.1001-5485.2015.02.012

Cited in this article [1] Abstract

The heavy rainfall and mist flow induced by flood discharge atomization of high dam projects may have negative effect on the hydropower project and its surrounding environment. Researchers have done much work on its influence region and rainfall intensity distribution on the downstream banks. Because of the complexity of this phenomenon, the formation mechanism of the flood discharge atomization is still not well revealed. Using high speed video technique in simplified hydraulic model tests, we observed the formation process of flood discharge atomization when a deflecting flow nappe drops into the downstream pool in different hydraulic conditions. We especially focused on the movement of the flow nappe and surface water around the drop area, and then analysed the components of different sources and their features. We obtain that the flood discharge atomization source could be divided into two types: dropping caused by the instability and aeration of nappe, and splashing caused by the collision between nappe and downstream water. Specially, the formation of the splashing atomization source is closely related with the periodical formation and dissipation of water surface bulges in the nappe drop area.