Journal of Hydroelectric Engineering

水力发电学报

Office Online

Included Databases

The journal is included in the following databases:
(i)Scopus,
(ii)The Chinese Science Citation Database Source Journals,
(iii)The Chinese Science Journal Abstract Database,
(iv)The Chinese Science and Technology Papers Statistics and Analysis Database,
(v)China Newspaper Subscription Guide Information Database,
(vi)Chinese Academic Journals (CD).


2022 Vol. 41, No. 11 Published: 2022-11-25

	1	Simulations of chlorophyll a concentration in a large shallow lake
		TANG Caihong, YI Yujun, ZHEN Haobei, ZHANG Cheng, ZHOU Yang, ZHANG Shanghong
		DOI: 10.11660/slfdxb.20221101
		Chlorophyll a (Chl a) is an important environmental indicator for lake primary productivity assessment, eutrophication control, and water ecological restoration. This study presents an analysis of the temporal and spatial characteristics of 12 water environment factors of a large shallow Baiyang Lake, based on a field survey of 11 sampling sites in spring and summer. We construct a generalized additive model and discuss the correlation between Chl a and water environmental factors. The results show the environment factors in the lake under strong human disturbance featured obvious temporal and spatial heterogeneity. The Chl a concentration was significantly correlated with six environmental factors－total nitrogen, ammonia nitrogen, transparency, phosphate contents, nitrate nitrogen, and dissolved oxygen－and the first four are the most critical. The interpretation rate of this generalized model is 98.9% for the Chl a content, and verification against the measurements shows its reliability. The results help understand the algal growth in Baiyang Lake and improve its algal bloom prevention and water environmental protection.
		2022 Vol. 41 (11): 1-10 [Abstract] ( 160 ) PDF (2270 KB) ( 261 )

	11	Effect of curved channel on flow structure with vegetation patch
		HE Mengxing, LIN Yingdian, HUANG Tianwei, YUAN Yeping
		DOI: 10.11660/slfdxb.20221102
		To understand the changes in the characteristics of flow structure caused by an emergent vegetation patch over a curved channel, laboratory experiments were conducted on a 180-degree U-shaped flume. Wooden cylinders were used to simulate a sparse vegetation patch and solid cylinders mimicked a dense vegetation patch; in each case, the patch position in the U-bend was the same to clarify the bend effect. An acoustic Doppler velocimeter (ADV) was used to measure the three-dimensional velocity. Experimental results show that the adjustment length upstream from the patch and the length of the stable wake region are adjusted significantly by the curved channel. And both the vegetation density and curved channel work together on the wake structure behind the patch, including but not limited to the difference in vertical turbulent kinetic energy (TKE), while the upstream adjustment length is not affected by vegetation density. Behind the vegetation patch, turbulence structure changes significantly, and large vortices appear on a scale comparable to the patch size, resulting in an obvious peak of the longitudinal TKE distribution. The peak value is also affected by the curve. However, it becomes smaller once the vegetation patch is moved to a position closer to the bend outlet. This trend is also found in turbulence spectrum analysis, showing the channel bend increases the number of small-scale turbulent eddies behind the patch. Therefore, small peak values caused by small-scale turbulent eddies do not depend on the relative patch position in the curved channel.
		2022 Vol. 41 (11): 11-20 [Abstract] ( 103 ) PDF (3217 KB) ( 249 )

	21	Integrated modelling of hydrological and hydrodynamic processes in watershed-rivers and navigation-hydropower project system of lower Xiangjiang River
		XU Chenhui, HUANG Guoxian, XIA Bo, JIANG Dongqing, HU Wei, LV Zhengze
		DOI: 10.11660/slfdxb.20221103
		An integrated hydrological and hydrodynamic model is developed and applied to the watershed and river network system of the lower Xiangjiang River, coupled with high-frequency operations of the Changsha navigation-hydropower project. It is configured, validated and verified using detailed riverbed topography, high-frequency data collected from nearly 80 stations at the time interval of 5 to 60 min during 2016-2021, and land use data with a resolution of 30 m. And the hydrodynamics and inundation processes with and without the project are calculated and compared. The results show the calculated water levels and flows in the rivers agree well with the high-frequency measurements, and the Nash Sutcliffe efficiency (NSE) is greater than 0.91 from the verification of Xiangtan, Langli, and other stations. The project operation and scheduling raised the water level and reduced the average flow velocity significantly in the backwater sections of the main river and its tributaries in the dry season, so that small-scale fluctuations in water level and flow were intensified and even reverse flows occurred in certain sections of the lower Liuyang and other rivers. For the incoming hourly flow at the frequencies of 1%, 50% and 99%, the calculations of water level and flow velocity in the river network reveal that the project scheduling increased the frequency of inundation in the sections of sand shoals and point bars in the upstream of the main river and its tributaries in the normal and dry seasons. This study demonstrates a new method and its application for quantitative assessment to the impacts of high-frequency scheduling of dams on the river system.
		2022 Vol. 41 (11): 21-33 [Abstract] ( 124 ) PDF (1629 KB) ( 210 )

	34	Real-scale 3D modeling of hydraulic characteristics of vertical inlet and outlet using SPH method
		ZHANG Chen, LI Tianguo, GAO Xueping
		DOI: 10.11660/slfdxb.20221104
		Pumped storage power station is an important regulating facility of the clean energy system; the hydraulic characteristics of its inlet and outlet directly affect its operation, maintenance and benefits. For the vertical inlet and outlet, most of its previous models used the grid-based Euler method, but their modelling accuracy of the flows around its orifice was low due to the bend turning. To overcome this issue, our study applies a meshless method of Lagrangian Smooth Particle Hydrodynamics (SPH) to simulate the flows in a vertical inlet and outlet connecting to a bend, by using tens of millions of particles for a real-scale simulation that is realized via GPU hardware acceleration. For the two conditions of power generation and pumping, the relative errors of the SPH method are 15.8% and 19.5% respectively in the head loss coefficient of the section from the head reservoir to the straight pipe, and 6.3% and 3.2% in the flow velocity nonuniformity coefficient of the orifice section, in comparison with the physical model measurements. The simulated flows show a good agreement of the bend section with the PIV measurements, and reveal that flow separation occurs in the diffusion section more remarkably; they reveal that no vortex is observed near the diversion cone and the orifice recirculation zone is smaller in area than that of the FLUENT case of no bend section. We find that the SPH method is more effective in simulating complex turbulent structures such as flow separation and secondary flows than the Euler method, and that our real-scale 3D SPH method is superior in producing flows around an abrupt wall shape change closer to the real cases, manifesting a great potential of further application.
		2022 Vol. 41 (11): 34-45 [Abstract] ( 108 ) PDF (4408 KB) ( 326 )

	46	Comparison of sediment carrying capacity to sediment concentration in upper reaches of Yangtze River
		LIU Shangwu, WANG Zhili, LI Danxun
		DOI: 10.11660/slfdxb.20221105
		The ratio of the sediment carrying capacity (S) of a river flow to its local sediment concentration (S) serves as a direct indicator of topographic change in riverbed. We have collected the field data of the upper Yangtze measured at its major hydrological stations in 2010-2020, and conducted an analysis of the ratio S/S. The results show that with a few exceptions, the carrying capacity generally exceeded local sediment concentration, and S/S presented a first-increase-then-decrease pattern of variation with flow discharge. This pattern is closely related to upstream dam operation and earthquakes－e.g., impoundment of the Xiluodu and Xiangjiaba reservoirs since 2013 led to an increase in S/S at the same flow discharge, while a decrease in S*/S has been observed at the Xiaoheba and Fushun stations in recent years due to the gradually reducing effect of earthquakes. The findings in this study provide a new insight for understanding sediment transport and promoting channel regulation in mountainous rivers.
		2022 Vol. 41 (11): 46-55 [Abstract] ( 226 ) PDF (558 KB) ( 341 )

	56	Analysis of multi-entity profit and loss relationship in hydro-wind-solar power complementary operation
		JING Zhiqiang, WANG Yimin, WANG Xuebin, CHEN Yunhua, ZHOU Yong, ZHAO Mingzhe
		DOI: 10.11660/slfdxb.20221106
		In the multi-energy complementary mode, the operation of hydropower-based flexible power sources will make a significant change to match the outputs of wind and solar power, thereby complicating the profit and loss relationship between different power generation entities. If the relationship between the different main entities is not clarified effectively or no compensation mechanism takes effect, it will be difficult to bring into play the enthusiasm of various power sources in participating in the integrated operation. This paper analyzes the profit and loss indexes of different power sources under three hydro-wind-solar power operation scenarios in the typical days of different seasons, and quantifies their profit and loss relationship, via a case study of a clean energy base in the lower Yalong River. The results show that under the multi-energy complementary operation mode, the total benefit of the hydro-wind-solar power system is increased significantly by 13.5% and 13.4%, along with a huge rise in the wind-solar power benefit of 123.3% and 146.0% in Scenarios 2 and 3, respectively, while the hydropower loses its benefit due to compensating for the other two sources by 0.33% and 3.21% for these two scenarios.
		2022 Vol. 41 (11): 56-67 [Abstract] ( 156 ) PDF (3582 KB) ( 365 )

	68	Medium- and long-term optimal scheduling of hydro-solar power system considering short-term complementation
		HUANG Xianfeng, XIANYU Hucheng, XU Chang, LI Dacheng, WU Di, LI Xu
		DOI: 10.11660/slfdxb.20221107
		To overcome the power consumption and fluctuation in the power transmission of a hydro-solar power system to ensure the stability of the power grid, we present a hydro-solar floating compensation method for compensating photoelectric random fluctuations successively, integrating the information of power quantity and output complementation, and identifying short-term power loss and fluctuating compensation power by using capacity information. On this basis, we develop a hierarchical scheduling model for maximizing medium- and long-term power consumption and taking into account the short-term risks of power abandonment and fluctuation. The results show that in comparison with short-term complementation, either medium- or long-term one can better allocate the time-capacity characteristics of hydropower and improve long-term consumption while taking into account short-term risks. A single-peak curve distribution relationship holds between the power consumption gain effect and the runoff guarantee rate, and the gain in the normal hydrological year is the most significant; the stability gain effect is positively correlated with the runoff guarantee rate, and it is the most obvious in the dry year. Thus, our method, by combining the effect preferences of both, can improve the applicability of scheduling decisions to different inflow scenarios.
		2022 Vol. 41 (11): 68-78 [Abstract] ( 124 ) PDF (1250 KB) ( 312 )

	79	New method for measuring time constant of synchronous motor rotor
		LUO Teng, JIA Wei, YANG Chaoting, LIU Xiuyi
		DOI: 10.11660/slfdxb.20221108
		The rotor time constant of a synchronous generator plays a key role in the modeling of the generator excitation system; dynamic response characteristics, starting time and inverter time, along with the compensation effect of the power system stabilizer, are all related to this parameter. The previous measurement methods of this constant are more or less limited and inconvenient. This paper develops a new method for its measurement, and discusses the feasibility through analysis of the measuring principle. This method and its measuring accuracy are verified and compared with numerical simulations and the existing methods, showing its convenience and reliability for engineering application as a new choice.
		2022 Vol. 41 (11): 79-85 [Abstract] ( 121 ) PDF (1088 KB) ( 265 )

	86	Hydrokinetic energy harvesting from flow-induced motion of circular-triangle-attachment oscillator
		RAN Danjie, LIAN Jijian, SHAO Nan, YAN Xiang, LIU Fang, YANG Xu
		DOI: 10.11660/slfdxb.20221109
		Aimed at the issue of the flow-induced motion energy conversion system (FIMECS)－limited utilization of the energy in hard galloping branches, a new type of oscillator with a circular-triangle-attachment (Cir-Tri-Att) combined section is developed. The existing FIMECS is refitted and equipped with a torque sensor to capture fluid forces, and experimental tests are conducted on this oscillator under different excitation voltages, focusing on its flow-induced vibration and power generation capacity. Its amplitude, frequency, lift, active power, and energy conversion efficiency are discussed and analyzed. This study aims to work out a new idea for improving the power generation of the real energy conversion system and to broaden its application scope. In the vortex-induced vibration range, the oscillator captures more flow energy in the case of larger flow velocity; its vibration response shifts from soft galloping to hard galloping as its damping increases; its best branch energy conversion is in the galloping branch. In our test range, its maximum amplitude ratio is 2.43 at an excitation voltage of 3 V and a reduced velocity of 12.4. And it features a peak active power of Pharn = 24.7 W and a peak efficiency of ηharn = 25.5%, corresponding to the excitation voltage of 99 V and reduced velocity of 12.4. Compared with the triangular prism, its energy converting capability improves to a certain extent.
		2022 Vol. 41 (11): 86-95 [Abstract] ( 126 ) PDF (1803 KB) ( 270 )

	96	Intelligent text classification and knowledge mining of hidden safety hazards in hydropower engineering construction
		WANG Renchao, ZHANG Yiwei, MAO Sanjun
		DOI: 10.11660/slfdxb.20221110
		Knowledge mining based on hidden danger troubleshooting information plays an important role in supporting engineering safety management; the natural language processing (NLP) technology is an important method to realize text knowledge mining. The depth and accuracy of knowledge mining are the key indicators of such methods. This paper presents a new hidden hazard text knowledge mining method that combines text classification and text mining technology to improve its efficiency in application to hydropower projects. It uses the RoBERTa-wwm-CNN hybrid deep learning model to make a fast intelligent classification of hidden hazard texts. On this basis, it realizes a visual analysis of the key points of hidden danger management through drawing a nephogram for hidden hazard words, and analyzes inner links among latent danger data via constructing a word co-occurrence network. Application to a hydropower station for comparison with the existing advanced text classification models shows that our new model is better in accuracy and applicability.
		2022 Vol. 41 (11): 96-106 [Abstract] ( 175 ) PDF (3783 KB) ( 343 )

	107	Influence of failure criterion fuzziness on seismic vulnerability of core rockfill dams
		LI Xingchen, SU Zhe, HUANG Qingfu, YANG Yang, WANG Xiaoling, YU Jia
		DOI: 10.11660/slfdxb.20221111
		The earthquake failure of core rockfill dams is a gradual process, but deterministic failure criteria were adopted in its previous seismic vulnerability studies, and the classification of its grades is ambiguous due to limited understanding of its mechanism and grades. This paper describes a seismic vulnerability analysis method for core rockfill dams, considering the fuzziness of failure criteria. First, the fuzzy set theory is used to fuzzily the threshold values of dam damage levels; and to quantify the seismic fuzzy damage levels, we formulate a fuzziness coefficient that reflects the membership function form and the size of the fuzzy interval. Then, a fuzzy-probability integral formula for calculating the seismic vulnerability function is derived from the fuzzy seismic damage level. For the calculation, this formula makes up for the deficiency of its existing formula that is based on the deterministic failure criterion. Combined with the probabilistic seismic demand model, this new formula gives a dam seismic vulnerability curve under the fuzzy failure criterion and predicts the probability of dam structure failure at different levels corresponding to different earthquake intensities. Our method is applied to the seismic vulnerability analysis of a core rockfill dam in Southwest China. Results show that the seismic fragility curve obtained using the fuzzy failure criterion follows a trend similar to the traditional curve. Under the fuzzy criterion, the subsidence rate of the dam crest increases the membership degree for high-level damage, resulting in an increase in the probability of high-grade dam body failure under the same earthquake intensity. And a greater ambiguity coefficient means a greater impact of the failure criterion ambiguity on seismic vulnerability.
		2022 Vol. 41 (11): 107-116 [Abstract] ( 77 ) PDF (1658 KB) ( 225 )

	117	Influence of mica particle size and content on mortar properties
		ZHENG Shunxiang, YAN Yong, WANG Ruiyijia, LI Jiazheng, SHI Yan, LI Yang
		DOI: 10.11660/slfdxb.20221112
		Mica is a main rock-forming mineral that widely exists in artificial sand; its content in aggregate may be high and affect the performance of concrete significantly. In this work, we study the effects of two kinds of mica common in engineering on the workability, mechanical properties, deformation properties, and crack resistance of cement mortar considering different mica particle sizes and different mica contents. Based on the formation mechanism and quality characteristics of mica, its influence on the properties of mortar is examined. The test results show that at a small particle size and a low content, mica has little effect on the mechanical properties of mortar; at a small particle size and a high content, it has great influence on the volume stability of mortar. The higher the mica content, the worse the crack resistance of cement mortar.
		2022 Vol. 41 (11): 117-123 [Abstract] ( 168 ) PDF (1928 KB) ( 135 )

	124	Spatiotemporal hybrid model for deformation of mortar masonry dams with time-varying factor
		SU Yan, ZHENG Zhiming, LIN Chuan, LIN Youlong, HE Qiang, ZHANG Ting, HUANG Shuxuan
		DOI: 10.11660/slfdxb.20221113
		Hybrid models are often used to predict the overall deformation of dams. However, most previous studies have focused on concrete dams, lacking an effort into the widespread masonry dams. This paper considers the time-dependent characteristics of nonlinear dam material, and constructs a corresponding multi-point statistical model of the hydrostatic component by introducing a time parameter and the relative coordinates for the observation points. Generally, difficulties exist in optimizing the coefficients of a hydrostatic component model if it is equipped with multiple parameters; thus, we proposed an improved particle swarm optimization (IPSO) algorithm to enhance the particle randomness and interactivity and accelerate the search for optimal model coefficients. By combining finite element method (FEM) and a Kalman filter (KF), a FEMK model is constructed and used for predictions. And a deep learning algorithm LSTM model is used to train the temperature and aging factors after PCA dimensionality reduction and to predict the corresponding deformation. The resultant model, namely the spatiotemporal hybrid model FEMK-LSTM-PCA jointly constructed by these two models, has a high accuracy in the overall prediction of dam deformation, which is verified by its application to engineering examples.
		2022 Vol. 41 (11): 124-138 [Abstract] ( 123 ) PDF (8413 KB) ( 62 )

	139	Experimental study on identification resolution of resistivity abnormal zones in hydraulic concrete
		MENG Yongdong, TIAN Shuangcen, CAI Zhenglong, TIAN Bin, ZHU Chao
		DOI: 10.11660/slfdxb.20221114
		The resistivity of hydraulic concrete with internal defects shows local high and low resistance anomalies. It is the key of high-density electrical nondestructive tests to enhance the identification resolution of high and low resistance zones through different electrode arrangements. An experimental study is conducted using three electrode arrangements of α, β and γ to explore the identification resolution of resistance abnormal bodies, by simulating the abnormal bodies in the concrete with materials of similar high and low resistance. The test results show that the abnormal body specimens from high to low resolution are ranked as α > β > γ for high resistance, γ > β > α for low resistance, and β > α > γ for high-low resistance. This means that the arrangement α is better for the concrete defects of holes and cavities, γ better for those of leakage, and β for those of holes, cavities, leakage, etc. The results help promote the application of high-density electrical methods in the nondestructive tests of hydraulic concrete.
		2022 Vol. 41 (11): 139-148 [Abstract] ( 73 ) PDF (3149 KB) ( 198 )

	149	Experimental study on prestressed concrete mix proportions for composite lining structure
		LU Andian, TANG Xinwei, YAN Zhenrui, MAI Shengwen, YAO Guangliang
		DOI: 10.11660/slfdxb.20221115
		To solve the concrete pouring difficulties in the construction of a composite lining under high internal pressure, such as the void forming in the vault and low pouring compactness in dense areas, this study conducts full-scale model tests for application of three different mix proportions of prestressed concrete in a double-layered steel strands lining structure. Concrete pouring quality is controlled by a device suitable for monitoring the voids in the vault, and pouring effects of different mix proportions are compared and analyzed. The results show that (1) better pouring effect is obtained by changing the aggregate of ordinary concrete from two-graded to one-graded and adopting a reasonable vibrating technology. (2) Self-compacting concrete can reduce the voids in the vault and improve pouring quality, but it needs to control material shrinkage and creep deformation and take certain temperature control measures. (3) The temperature of concrete flattens out in 8 - 10 days. This study recommends that in the case of the steel strands under tension, the curing should not be less than 14 days.
		2022 Vol. 41 (11): 149-158 [Abstract] ( 175 ) PDF (4098 KB) ( 172 )

	159	Flow filling and temperature rise of rock-filled concrete based on prototype monitoring
		XU Xiaorong, YU Shunyao, JIN Feng, QIU Liuchao, XIAO Anrui
		DOI: 10.11660/slfdxb.20221116
		Flowing and filling process of self-compacting concrete (SCC) in the complex voids of rockfill is of high concealability, so it is difficult to scientifically quantify the filling effect of rock-filled concrete (RFC). This study conducts an in-situ monitoring and experiment on SCC at Shibahe gravity dam: lay temperature sensors at different locations of a typical section; measure real-time fresh concrete levels; track pouring locations; record the instants of monitoring sensors covered by fresh concrete mixture. And the free surface profiles of fresh SCC are plotted for different instants. The test results show SCC has a great lateral self-flow filling capacity－it can flow and reach the monitoring section 17 m away from the pouring location. In pouring and filling of the fresh SCC, its surface levels upstream and downstream of the section keep a trend of rising at nearly constant speeds. The slope I_s of the free surface is about 0.03 - 0.08 upstream and downstream of the section and roughly 0.06 along the dam axis in the whole impermeable layer. The damping coefficient η of the rockfill voids is about 65 - 173 in theoretical calculations. Analysis of the temperature data of rockfill-SCC mixture reveals that during pouring, its spatial distribution starts from heterogeneous but approaches relatively uniform soon after mixing. The process of flow filling and temperature rise in the mixture observed in-situ synchronously is of great significance for further quantitative evaluation of RFC compactness and mesoscopic temperature distribution.
		2022 Vol. 41 (11): 159-170 [Abstract] ( 136 ) PDF (5382 KB) ( 352 )