Search Results (14)

The increasing demand for water in arid regions has driven the adoption of seawater desalination plants as critical infrastructure for industrial and domestic applications. However, these plants face unique challenges, including high operational costs, environmental vulnerabilities, and system reliability concerns. The critical nature of these infrastructures demands maintaining elevated levels of availability and demonstrating robust resilience. Resilience is framed as the system’s capacity to recover from disruptions and maintain operational efficiency under varying conditions. Quantitative assessment of resilience is essential to facilitate the development and implementation of optimal strategies that ensure operational continuity. This paper puts into practice a novel approach to evaluate the resilience of a seawater intake and pumping system using permutation entropy computed using time series availability data derived from different maintenance strategies. The methodology integrates reliability block diagrams (RBD) and symbolic time series analysis to identify critical components and evaluate maintenance strategies. A case study of a seawater pumping station demonstrates the application of the proposed resilience index. The analysis explored four scenarios to evaluate how these changes improved the system’s resilience: the first three hypothetical scenarios involved testing improvements in the maintainability and reliability indexes of the critical pump. These improvements matched the values of these parameters to the benchmark of the pump, historically showing the best indicators, first one by one, separately, and then both changes simultaneously. The initial resilience index was 0.652 in the baseline scenario. Scenario 1 (reduction in MTTR) showed a negligible impact, while scenario 2 (reduction in downtime) increased the resilience index to 0.682. The combination of both (scenario 3) maintained the index at 0.682, emphasizing the importance of reducing downtimes. Scenario 4, which consisted of reducing and standardizing the frequency of planned maintenance to 100 h, significantly raised the resilience index to 0.778. The results highlight how adjustments in maintenance strategies, including the reduction in preventive interventions, impact the system’s resilience and availability. The study also underscores the importance of aligning maintenance strategies with resilience goals to enhance the operational reliability of marine infrastructure. By providing a quantitative tool for resilience assessment, this work contributes to the sustainable management of desalination plants and offers practical insights for engineers and decision-makers in the marine engineering and water management sectors. Full article

Double suction pumps are widely used in the Yellow River in the China water intake pump stations, which face serious sediment wear. A prediction model for gap erosion in gas-liquid solid three-phase flow was constructed. A gas core factor has been added to the gap erosion model to achieve accurate prediction of particle impact velocity and impact angle caused by cavitation air core deformation. The influence mechanism of cavitation flow and sand-laden suction vortex on the sediment erosion. Usually, double suction pumps are one type. This study aims to explore the effects of the symmetrical and asymmetrical installation of double suction pump impellers on the wear and energy dissipation of pumps under sediment conditions in three-stage centrifugal pumps. The research results indicate that under symmetrical installation, the wear of the impeller caused by sediment impact is significantly intensified with a maximum velocity of 27 m/s. In contrast, asymmetric installation significantly improves sediment wear, with a maximum velocity of 24.3 m/s. By optimizing the staggered angle on both sides of the impeller, it was found that when the staggered angle was set to 10.85°, the performance of the pump under sediment conditions reached its optimal level, with a minimal erosion rate of 0.000008 kg·m⁻²·s⁻¹. These results provide an important basis for the design and optimization of three-stage centrifugal pumps in sediment transport and have significant theoretical significance and engineering application value. Full article

The vortices, backflow, and siltation caused by sediment-laden flow are detrimental to the safe and efficient operation of pumping stations. To explore the effects of water–sediment two-phase flow on the velocity field, vorticity field, and sediment distribution within intake structures, field tests and numerical simulations were conducted in this study with consideration for the sediment concentration, flow rate, and start-up combination. We applied a non-contact laser scanner and ultrasonic Doppler velocimetry to obtain the field data and reverse modeling of the three-dimensional model of the intake structure under siltation. A multiphase flow model based on the Euler–Euler approach combined with the k-ε turbulence model was adopted for numerical simulation under 10 working conditions, and the reliability was verified with field data. The results indicate that sediment promotes the evolution of coaxial vortices into larger-scale spiral vortices along the water depth, and the process of sediment deposition is controlled by the range, intensity, and flow velocity of the backflow zone. Furthermore, the maximum volume fraction of the near-bottom sediment increased by 202.01% compared to the initial state. The increase in flow rate exacerbates the turbulence of the flow field. Although the increase in sediment concentration benefits the flow diffusion, it further promotes sediment deposition. This study provides a new idea for modeling complex surfaces and considers different operating conditions. It can serve as a scientific reference for the structural optimization and anti-siltation design of similar water-conservancy projects. Full article

The site selection of hydraulic structures is crucial to the successful implementation of water conservancy projects. Reasonable or not, site selection has a direct impact on the functioning of hydraulic structures, engineering safety, and environmental impact. In this paper, the proposed Wanfu River Guanqiao Ship Lock and Pumping Station engineering is utilised as the object. The MIKE model is executed to simulate both the impact of Guanqiao Ship Lock operation on the water quality of the pumping station intake as well as the effects of pumping station operation on the navigable water level in order to analyse and demonstrate the reasonableness of the pumping station’s location. According to the water quality monitoring data of the last three years, the entropy weight method coupled with the comprehensive pollution index method was used to evaluate the water quality of the Wanfu River. A one-dimensional hydrodynamic water quality model was constructed by applying MIKE11, which reveals the change rule of water quality and also demonstrates the safety of navigable water levels. The MIKE21 two-dimensional water quality model, which intuitively displays the spatial and temporal patterns of change of each indicator, was constructed. The results show the following: (1) The evaluation results of the entropy weight method coupled with the comprehensive pollution index method indicate that the water quality of the Wanfu River is Class III, which meets the water intake standard. (2) Concentrations of the indicators are higher in the abundant water period than in the dry water period, in which the water quality is Class IV in June and July. (3) There is no impact of the pump station operating on navigable water levels. Full article

The increase in electricity generation prices represents a reason why water utility companies are looking for ways to reduce costs. One of the first ideas of users was to build photovoltaic installations. Water treatment plants or sewage treatment plants usually have large unused areas. They look different in facilities that consume a lot of energy but occupy little land, and include water intakes (wells) and water pumping stations. Facilities equipped with pumps are characterized by high electricity consumption. This article assesses the possibility of using PV installations at the water intake. An analysis of energy production from the 3.0 kW PV installation in Polanica-Zdrój was carried out, and then, simulations of the possibility of providing energy via installations with capacities of 3.0 kW, 4.2 kW, and 6.0 kW were performed. Analyses of energy production and demand, as well as analyses of water production based on annual, monthly, daily, and hourly data, were performed. An analysis of the hourly coverage of the WPS’s demand for electricity was carried out with regard to the current production of energy from the PV installation, as was an analysis of the overproduction of energy from the PV installation regarding the energy demand of the WPS. The simulation results are presented for cloudy and sunny days. Full article

Pump station engineering is a water conservancy project that utilizes water pump units for energy transfer and conversion, and safe water transportation. This study ensures the safe and efficient operation of the pumping station system by taking a pump station project containing seven water pump units as the research object. Under the premise that the total water intake of the pumping station is certain, the flow distribution of the pumping station is optimized with the working flow and head as the constraint function, and the minimum operating cost as the objective function, and the required number of operating units is determined to obtain the optimal combination of flow distribution and the corresponding working flow of each operating unit. Compared with previous studies, the novel feature of this study is that a genetic algorithm is used to optimize the power-up combination and rationally distribute the flow, which can minimize the energy consumption and maximize the operation efficiency of the pumping station. Then, a genetic-algorithm-based optimization method is constructed for unit operation combination and flow distribution. The optimized combination of units is evaluated by using the uniformity of flow velocity at the inlet section of the water pump and the average deviation angle of the section as indicators. The results indicate that, when each operating unit in the pump station has the same working flow distribution, the total input power of the pump station is at maximum. As the differences increase in the working flow rates allocated to each operating unit, the total input power of the pump station decreases. Through the proposed schemes, the optimal operating combination and flow distribution of the pump station system can be achieved when the total water intake is constant, thereby enabling efficient operations and creating maximum economic and social benefits. Full article

Water supply systems that use rivers with high sedimentation levels may experience issues such as reservoir siltation. The suspended sediment concentration (SSC) of rivers experiences interannual variation and high nonlinearity due to its close relationship with meteorological factors, which increase the mismatch between the river water source and urban water demand. The raw water system scheduling problem is expressed as a reservoir and pump station control problem that involves real-time SSC changes. To lower the SSC of the water intake and lower the pumping station’s energy consumption, a deep reinforcement learning (DRL) model based on SSC prediction was developed. The framework consists of a DRL model, a hydraulic model for simulating the raw water system, and a neural network for predicting river SSC. The framework was tested using data from a Yellow River water withdrawal pumping station in China with an average capacity of 400,000 m³/d. The strategy created in this study can reduce the system energy consumption per unit of water withdrawal by 8.33% and the average annual water withdrawal SSC by 37.01%, when compared to manual strategy. Meanwhile, the deep reinforcement learning algorithm had good response robustness to uncertain imperfect predictive data. Full article

In order to study the hydraulic performance and internal flow field of dual pumps in centrifugal prefabricated pumping station under operation conditions, this paper carried out a numerical calculation based on CFD software for dual pumps in a centrifugal prefabricated pumping station under different flow conditions and verified the internal flow field through test. The results show that the efficiency of centrifugal prefabricated pumping station under design conditions (Q_d = 33.93 m³/h) is 63.96%, the head is 8.66 m, the head at the starting point of the saddle area is 10.50 m, which is 1.21 times of the designed head. The efficiency of the high-efficiency zone of the prefabricated pump station is 58.0~63.0%, and the corresponding flow range is 0.62Q_d~1.41Q_d (21.0~48.0 m³/h). The uniformity of the inlet flow rate of impeller of pump 1 is 74.70%, and that of pump 2 is 75.57%. The flow fields of water pumps on both sides are inconsistent. The results of the flow field indicate that there are severe back flow phenomena at the prefabricated bucket intake, more back flow in the bucket, and many eddies on the side wall. With the increase in flow rate, the eddy structure at the intake expands continuously and moves towards the center area, which has a negative impact on the flow field in the center area. The research results of this paper can provide a theoretical reference for the research and operation of the same type of prefabricated pumping stations. Full article

To improve the problem of turbulence in the forebay of the lateral inlet pumping station, a typical lateral inlet pumping station project in Xuzhou, Jiangsu Province, China was taken as the research object. The forebay of the pumping station is a building connecting the river channel and the pumping station into the water tank. Based on the Reynolds-averaged Navier-Stokes (RANS) law and the k-ε turbulence model, the computational fluid dynamics method (CFD) technology compares and analyzes the numerical simulation with or without rectification measures for the forebay of the lateral intake pumping station when multiple units are operating. The three-dimensional model was created by SolidWorks modeling software and the numerical simulation simulated by CFX-ANSYS. To alter the flow pattern in the forebay of the pumping station, various rectification measures were chosen. Internal rectification flow patterns in the forebay under multiple plans, uniformity of flow velocity distribution in the measuring section, and vortex area reduction rates are investigated and compared. Based on the analysis and comparison of numerical simulation results, when the parabolic wall and some rectification piers are set significantly it improves the flow pattern of the forebay of the lateral inlet pumping station. It also makes the flow pattern of the inlet pool better and increases the uniformity of the flow velocity distribution by 8%. Further, it reduced the vortex area by 70%, effectively improving the operating efficiency of the pump. The research results of this paper provide a technical reference for the improvement of the flow pattern in the forebay of the lateral inlet pumping station. Full article

The forebay of a pumping station is an important building connecting the diversion channel and the intake pool. Based on the physical model test and research method of computational fluid dynamics (CFD) based on the improved fluid volume model, the flow field in a forebay of a multi-unit pumping station is analyzed in combination with the engineering practice of the Exi River flood discharge station in the Anhui Province, China. Aiming at the technical problems of a large-scale swing water area in the forebay internal flow field of a lateral intake pumping station, the technical problems are discussed. Different rectification measures are selected to adjust the flow pattern in the forebay of a pumping station. The internal rectification flow pattern in the forebay under different plans, the uniformity of flow velocity distribution in the measurement section, and the reduction rate of the vortex area are studied and compared, and the optimal plan is given. The results show that the flow pattern of the 7.5 m and 15 m solutions of the lengthened inflow wall is still poor, and the ability to eliminate vortices is not strong or even counterproductive. The combination plan of a rectifier sill and a rectifier pier has a better effect and can eliminate more than 90% of the vortex, but the uniformity of flow speed has not been significantly improved at the inlet of the pumping station; the combination plan of a rectifier sill and a diversion wall opening has the best effect; the reduction rate of the vortex area is more than 85%, and the velocity uniformity of three measuring sections is better than that of the original plan. The uniformity of flow rate near the pumping station is increased by 4% and that far away from the pumping station is increased by 13%. The combination plan of a rectifier sill and diversion wall with openings is recommended. Full article

Pumping stations are important regulation facilities in a water distribution system. Intake structures can generally have a great influence on the operational state of the pumping station. To analyze the effects of the bell mouth height of the two-way intake on the performance characteristics and the pressure pulsations of a two-way pumping station, the laboratory-sized model pump units with three different intakes were experimentally investigated. To facilitate parameterized control, ellipse and straight lines were used to construct the profile of the bell mouth. The frequency domain and time-frequency domain of the pressure pulsations on the wall of intakes were analyzed by the Welch’s power spectral density estimate and the continuous wavelet transform (CWT) methods, respectively. The results showed that the bell mouth height (H) has significant influences on the uniformity of the impeller inflow and the operation stability of the pump unit. When H = 204 mm, the data fluctuated greatly throughout the test process and the performance curves are slightly lower than the other two schemes. As the bell mouth height gradually decreases, the average pressure difference of each measuring point began to decrease, more homogeneous velocity distribution of impeller inflow can be ensured. The amplitude of blade passing frequency is obvious in the spectrum. While when (H) is more than 164 mm, the main frequency of pressure pulsations at three points fluctuates with the rotation of the impeller. When H decreases to 142 mm, pressure pulsations will be independent of the operating conditions and positions which contributes to the long-term stable operation of the pump unit. Full article

Siltation is one of the most common problems in storage projects and attached structures around the world, due to its effects on a project’s life span and operational efficiency. A three-dimensional computational fluid dynamics (CFD) model was applied to study the flow and sediment deposition in a multipurpose reservoir (Mosul Dam Reservoir, Iraq) subject to water withdrawal via a pumping station. A suitable control code was developed for the sediment simulation in intakes with multiblock option (SSIIM) model, in order to simulate a study case and achieve the study aims. The measured total deposited load in the reservoir after 25 years of operation and the measured sediment load concentration at different points near the pumping station intake were considered to validate the model results. The sediment load concentrations at several points near the water intake were compared; the percent bias (PBIAS) value was 3.6%, while the t-test value was 0.43, less than the tabulated value, indicating fair model performance. The model sensitivity to grid size and time steps was also tested. Four selected bed level sections along the reservoir were compared with the simulated values and indicate good performance of the model in predicting the sediment load deposition. The PBIAS ranged between 4.8% and 80.7%, and the paired t-test values indicate good model performance for most of the sections. Full article

High flexibility of prefabricated pumping stations in collecting and transporting storm water has been recognized. Nevertheless, flows inside such a complex system have rarely been reported. The present study aims to reveal water-sand flow characteristics in a prefabricated pumping station and to optimize geometric parameters of the tank to mitigate sand particle deposition. Five tank schemes, varying in the ratio of the diameter to the height of the tank bottom (D/L), were investigated. Flows in the pumping station were simulated using the computational fluid dynamics (CFD) technique. Test data were used to validate the numerical scheme. Three-dimensional water-sand flows in the pumping station were described. Underlying mechanisms of sand particle deposition were explained. The results indicate that the risk of deposition is high at the tank bottom side, close to the tank inlet. Both the tank bottom geometry and the inlet suction of the pump contribute to sand particle deposition. The averaged sand volume fraction at the pump inlet reaches its minimum at D/L = 3. Sand particle velocity at the pump inlet varies inversely with D/L. The highest intensity of the vortex at the pump inlet arises at D/L = 3. The best anti-deposition performance of the pumping station is attained at D/L = 3. Full article

The maintenance of the performance of sump pumps is important to mitigate flood damage in urban areas and lowlands. However, the air-entraining vortex in the sump leads to undesirable performance degradation. Thus, in this study, the newly designed floating anti-vortex device (F-AVD) was employed in the intake pipe to enhance the efficiency of water intake in the sump by decreasing the surface vortex. The performance of the F-AVD was evaluated from the model experiments, in which the sump model was designed to represent the pump station that operates in Korea. The flow in the sump was measured using the particle image velocimetry (PIV) technique, and the velocity and vorticity distributions were compared both with and without the adoption of the F-AVD. The experimental results indicated that the vortex structures behind the intake pipe were effectively mitigated by installing the F-AVD. The vorticity magnitude behind the intake pipe was reduced in range of 24.8–52.5% after the installation of the F-AVD. However, in the case of a flow rate increase, the efficiency of the F-AVD decreased because of the strong vortex. Thus, an additional anti-vortex device (AVD), which is attached to the backwall or the floor in the sump, is required to prevent the air entrainment in conditions with high flow rates. Full article