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).


2020 Vol. 39, No. 3 Published: 2020-03-25

	1	Quantitative assessment of water stage changes of Poyang Lake in dry period and its influencing factors
		WANG Dan, ZHANG Shuanghu, WANG Guoli, WANG Hao
		DOI: 10.11660/slfdxb.20200301
		Lake wetlands play an irreplaceable role in maintaining biodiversity, ecological balance, and land surface mass balance. Poyang Lake is important for flood control and water source of the middle and lower Yangtze River and provides a unique hydrological condition for its rich habitats and biodiversity. Since the Three Gorges reservoir was put into operation, Poyang Lake has experienced an earlier and longer dry period, especially its abnormally low water stage in October that greatly imperils its function as an habitat for wintering birds. This paper presents a quantitative analysis of the water stage changes of Poyang Lake in October using a fuzzy division clustering model; and examines its influencing factors such as the river runoff, the Three Gorges reservoir’s water storage after flood period, and the corresponding change in the river and lake geography. Results show that a significant decrease in the Poyang inflow and the Yangtze mainstream runoff is the main cause for the lake’s stage falling, and that the reservoir impounding after flood season has further accelerated this falling. These results can provide a basis for lake management and improving the lake ecosystem and environment during the dry period of Poyang Lake.
		2020 Vol. 39 (3): 1-10 [Abstract] ( 285 ) PDF (826 KB) ( 980 )

	11	Study on exploitation status and potential of hydropower in countries along the Belt and Road
		GU Yu, PENG Dingzhi, ZHAO Keke, FAN Chuting
		DOI: 10.11660/slfdxb.20200302
		It is of great significance to analyze the exploitation status and potential of hydropower in countries along the routes of the Belt and Road to promote energy cooperation and building a community with a shared future. This study analyzes and summarizes spatial and temporal distribution characteristics of the hydropower resources and exploitation rates over six regions along the routes based on a large body of data. The results show that for hydropower resource, its theoretical potential and technically exploitable capacity decrease from the east to west, while its exploitation rate increases from the east to west and is lower than 50% in most countries. In the past five years, the number of countries with an increasing or decreasing hydropower output is equal. Northeast Asia and Southeast Asia have abundant hydropower resources, with an obvious increasing trend in hydropower generation and a great exploiting potential. This study suggests that the countries along the routes can be divided into five levels according to the ratio of their exploiting potential of hydropower to the total, and future efforts should be focused on the 16 countries at the first and second levels. We also suggest and emphasize that the strategy of energy development along the Belt and Road should adapt to the specific situations of different countries with more exchange, innovation and cooperation in the future.
		2020 Vol. 39 (3): 11-21 [Abstract] ( 194 ) PDF (2641 KB) ( 493 )

	22	Study on operation of flood control system for middle and lower Ganjiang River
		ZHU Di, MEI Yadong, XU Xinfa, WU Zhenhui, LAN Lan
		DOI: 10.11660/slfdxb.20200303
		This paper develops a flood control operation model for the middle and lower Ganjiang River that has a complicated flood control system comprising reservoirs, navigation-power junctions, and flood diversion and storage areas, with an objective to maximize the reduction rate of flood peaks at flood control cross sections. This model optimizes the system’s flood control operation using a dynamic programming-progressive optimization algorithm based on a discrete neighborhood, and its results are compared with those of conventional flood control operation, through a case study of the 1961 typical floods and the design floods of 50-, 100- and 500-year return periods. The results show that the optimized operation significantly reduces the flood peaks at the flood control sections to ensure the safety of downstream areas. And the cascade reservoirs and flood diversion area play an important role in the flood-control system of the Ganjiang basin, and the effect of navigation-power junctions is very limited. For the 1961 typical floods, operation of the navigation-power junctions can reduce the peak stage of the Xiajiang reservoir to a certain degree, helping enhance the reservoir safety of flood control.
		2020 Vol. 39 (3): 22-33 [Abstract] ( 171 ) PDF (447 KB) ( 510 )

	34	Runoff prediction based on variational mode decomposition and deep gated network
		LI Wenwu, SHI Qiang, WANG Kai, CHENG Xiong
		DOI: 10.11660/slfdxb.20200304
		To improve the accuracy in medium- and long-term prediction of reservoir runoff, this paper develops a combined prediction model integrating variational mode decomposition, phase space reconstruction, and a deep gated network. For a series of historical runoff data, this model first generates its multiple mode components using variational mode decomposition, and uses phase space reconstruction to reconstruct the components into a high-dimensional feature space to generate inputs for deep learning. Then, detailed characteristics of the series are obtained and predicted using a deep gated network, and the reconstruction is completed by superimposing the predicted values of the mode components. In a case study of the Baishan reservoir, this combined prediction model is compared with typical single prediction models and other combined prediction models. The results show that our method can effectively decompose non-stationary runoff series, learn the intrinsic hydrological patterns, and offer the smallest prediction error, the highest goodness of fit, and more reasonable error distributions over the whole test set, thus helping the planning and management of reservoir water resources.
		2020 Vol. 39 (3): 34-44 [Abstract] ( 390 ) PDF (725 KB) ( 945 )

	45	Experimental investigation on effects of salinity stratification on turbulence characteristics of water body
		HUANG Rui, ZHANG Qinghe, XING Enbo, ZHANG Jinfeng
		DOI: 10.11660/slfdxb.20200305
		Turbulent flows generated by double-layer transverse oscillation grids are used to study the turbulence characteristics of pure fresh water and salt water stratified with different salinity gradients. Time variations in turbulence and salinity are measured simultaneously using an acoustic Doppler velocimeter and a multi-channel micro-salinity meter that was designed in our laboratory. This paper focuses on an analysis of the effects of salinity stratification on turbulent characteristics such as root mean square velocity, turbulence intensity, and turbulent kinetic energy spectrum. The results show that the stratification suppresses turbulences and weakens turbulence intensity, and a larger salinity gradient leads to more suppression of turbulences. A dimensionless stratification parameter is defined to represent the stratification degree of a water body under oscillating grid turbulences. Our analysis reveals the turbulence suppression rate increases as this parameter is increased, and a relationship between them is obtained through data fitting.
		2020 Vol. 39 (3): 45-55 [Abstract] ( 166 ) PDF (4076 KB) ( 394 )

	56	Study on power grid stability of hydropower DC transmission project
		CHEN Dian, LIU Fei, TIAN Xu, ZHANG Jun, WANG Shibin
		DOI: 10.11660/slfdxb.20200306
		Qinghai-Henan UHVDC transmission project, the world's first large-scale use of DC transmission technology to transport hydropower and new energy over a long distance, is important to hydropower and new energy transmission. After it is put into use, new security and stability problems of the power grid will arise. This paper first analyzes the power grid’s stability characteristics after this clean energy DC transmission project put into operation. For the transient problem, the optimal control measures were design and examine to adjust the operation mode and reinforce the grid. Simulations and analysis show that the optimized operation mode and grid reinforcing scheme ensure the transmission of hydropower and clean energy and the DC transmission capability in transition period.
		2020 Vol. 39 (3): 56-65 [Abstract] ( 148 ) PDF (435 KB) ( 513 )

	66	Study on soil-water characteristics and compressive collapsibility of unsaturated lime loess
		LIANG Zhichao, HU Zaiqiang, GUO Jing, WANG Kai, FENG Zhe, SHE Haicheng
		DOI: 10.11660/slfdxb.20200307
		Aimed at the collapsibility of unsaturated loess in Northwest China, an unsaturated consolidation instrument is used to test matric suction and to conduct compression test of lime loess. Different contents of lime are added with different dry densities of the loess; various characteristics of the improved soil, including soil-water characteristic, compression property, moistening and collapse deformation, are measured and examined. Results show that lime content has little effect on the soil-water characteristic curve of lime-improved loess, while dry density produces a great influence. Compression index and yield stress increase with the increase in matric suction, while the expansion index is nearly independent of it. Under the same vertical pressure, the collapsibility coefficient increases with initial suction. As initial matric suction increases, initial collapse pressure decreases, while both the maximum collapsibility coefficient and highest collapse pressure increase. When lime content exceeds 3%, the collapsibility coefficient??s (p = 200 kPa) will be less than 0.015, indicating that the collapsibility of lime- improved loess is nearly eliminated, which can be useful in engineering application.
		2020 Vol. 39 (3): 66-75 [Abstract] ( 148 ) PDF (695 KB) ( 577 )

	76	Prediction of minimum void ratio of coarse-grained soil based on particle packing model
		WEN Xinan, MA Gang, WANG Feng, ZHOU Wei, LIU Qiwen, MEI Jiangzhou
		DOI: 10.11660/slfdxb.20200308
		The minimum void ratio is one of the most fundamental physical indexes of coarse-grained soil; but up to now, its direct prediction method is lacking for common or oversize coarse-grained soils with different gradations, and its calculation relies on laboratory and field tests. This paper presents a particle packing model for the direct prediction and verifies it through testing on the soil ideal sphere particles. Considering the complicated particle shapes of natural and engineering coarse-grained soils, linkages between the model parameters and particle shapes are needed; then we adopt a hypothesis of a power function relationship of the minimum void ratio versus particle size that holds true for monosize soils. We calibrate the parameters using an optimization algorithm and the experimental data of void ratio tests, and predict the minimum void ratio for different gradations. Application to several practical projects shows satisfactory results of this new method in predicting the minimum void ratio of common and oversize coarse-grained soils and its great value in engineering application.
		2020 Vol. 39 (3): 76-85 [Abstract] ( 233 ) PDF (498 KB) ( 520 )

	86	Modal parameter identification for Xiluodu arch dam
		LI Shuai, PAN Jianwen, LUO Guangheng, QIU Yixiang, SHI Hongtao, WANG Jinting
		DOI: 10.11660/slfdxb.20200309
		With a train of high arch dams built in Southwest China, the health of dam structures and their anti-seismic properties have become a hot issue in recent years. Modal parameters reflect the dynamic characteristics of dam structures and are applicable to evaluating dam health status and updating the finite element models for arch dam anti-seismic analysis. This paper presents a study on the identification of modal parameters for Xiluodu arch dam using the ARX, SSI and FDD procedures separately, based on two earthquake recorders located in Yongshan County and ambient vibration test data. The results show the modal parameters identified using ambient vibration tests agree with those identified using the recorded data. When the reservoir stage varies from 566 m to 598 m, the fundamental vibration frequency of this dam is lowered from 1.63 Hz to 1.51 Hz. And similar frequencies identified before and after the earthquakes indicate that the dam is in the normal operation condition.
		2020 Vol. 39 (3): 86-95 [Abstract] ( 217 ) PDF (1300 KB) ( 411 )

	96	Nonlinear dynamic analysis of hydropower generator shaft system under foundation excitations
		SUN Wanquan, ZHENG Zezhi
		DOI: 10.11660/slfdxb.20200310
		This paper presents a new dynamic model of the shaft system of a hydropower generator coupled with external random excitation from its foundation. We establish nonlinear dynamic differential equations for the shaft system, considering the nonlinear effects of rotor unbalance and runner sealing force; numerically simulate the influences of nondeterministic and random foundation excitations on the shaft’s transverse vibrations, using axis orbit diagrams, Poincaré maps and bifurcation diagrams, etc. The results show that the shaft system’s operational stability will be affected by variations in the frequency, intensity and spectrum width of the excitation, leading to its complicated nonlinear vibration behaviors such as period-doubling and chaotic motions. This study helps a deeper understanding of the influence and mechanism of the nonlinear dynamics of hydropower generator shaft systems.
		2020 Vol. 39 (3): 96-105 [Abstract] ( 147 ) PDF (765 KB) ( 420 )

	106	Prediction of dam deformation based on Bootstrap and ICS-MKELM algorithms
		WANG Xiaoling, XIE Huaiyu, WANG Jiajun, CHEN Wenlong, CAI Zhijian, LIU Zongxian
		DOI: 10.11660/slfdxb.20200311
		Traditional prediction methods are hardly applicable to the dam deformation featured with high dimensions and nonlinearity; they can predict the deformation at location points of a dam body, but fail to effectively quantify the uncertainties from data with random noise, subjectivity in input samples, and randomness in parameter selection. To solve this problem, we develop a new dam deformation prediction model based on the Bootstrap algorithm and an improved cuckoo search–multiple kernel extreme learning machine (ICS-MKELM) algorithm. The model quantifies the uncertainty through interval prediction and can realize accurate point prediction of dam deformation. First, based on high-precision MKELM, we construct a dam deformation prediction model that integrates the advantage of KELM efficiently handling strong nonlinear regression problems with the superiority of a hybrid kernel of high generalization and strong learning capability. And an ICS algorithm, based on the inertia weight and chaos theory, is adopted to optimize MKELM’s kernel parameters and regular coefficients, offsetting its disadvantage of easy falling into local optimization. Then, a Bootstrap interval prediction method is used to quantify the uncertainty from the model and data. Our model is applied to the deformation prediction of a real dam, and its consistency and superiority are demonstrated through an analysis on the influence of different sizes of the training sets on prediction accuracy and a comparison with other five commonly-used prediction algorithms.
		2020 Vol. 39 (3): 106-120 [Abstract] ( 237 ) PDF (2266 KB) ( 953 )