Hydraulic Network Analysis Research Articles

Hybrid method for hydraulic transient analysis of liquid pipe networks based on characteristic lines and equivalent circuits

Water hammer poses a significant concern in the transportation of pipelines and pipe networks. Due to the passage of reflection of water hammer waves at nodes, a large number of high-frequency pressure fluctuation signals appear in the pipe network, demanding an intensive computational workload. A novel hybrid method based on characteristic lines and equivalent circuits is proposed for the accurate and fast simulation of pipe networks. Multiple methods are employed for the simulation of pipelines and pipe networks, followed by a comparative analysis. The accuracy of the hybrid method is validated by comparing the proposed method with simulation results of commercial software. The hybrid method reduces the significant computational workload inherent in the classic method of characteristics and enhances the accuracy at high frequencies in the state-of-the-art elastic water column model. A trade-off between simulation accuracy and computation speed is achieved by adjusting the time step. The accuracy of calculating higher-frequency pressure fluctuations is further validated with an increase in the pipe diameter and a corresponding reduction in the friction loss. Generally, this method enables the simultaneous descriptions of high-frequency characteristics and nonlinear friction loss, enhancing calculation speed with little impact on the accuracy. The results demonstrate that the proposed model can be utilized for the transient analysis of pipe networks, providing support for predicting system performance and designing optimal strategies.

Data-driven hydraulic property analysis and prediction of two-dimensional random fracture networks

The large parameter space and uncertainty of the discrete fracture networks (DFNs) make the hydraulic characteristics have multiple possibilities. Statistical analysis of hydraulic characteristics based on a large amount of data is a standard practice and central to DFN methodology. The present study developed a two-dimensional (2D) DFN numerical seepage model based on Matlab and Comsol from modeling and parameter calculation to simulation to investigate the influence of parameters involved fracture network on seepage characteristics of DFNs. In total, 1728 2D DFN models were generated with increasing fracture density, fracture length, power-law exponent, fracture orientations, and fracture included angles, and 1728 × 3 = 5184 numerical simulations of fluid flow along the x-axis, y-axis, and center through the DFN models are conducted using a self-developed numerical code. The influence of fracture geometric features on connectivity and permeability are estimated, respectively. And to realize the prediction of permeability tensor by known geological data, a theoretical model based on the Snow model and a data mining model based on the back-propagation model are discussed. The analysis helps researchers and engineers can make informed decisions and develop effective strategies for addressing the challenges posed by uncertainty hydraulic property of the fractured rock masses.

Planning Of Raw Water Distribution Network Sumberrejo Village Candipuro District Lumajang Regency

Indonesians have an average domestic water consumption of 34.2 liters/person/day while the minimum amount to meet basic human needs is 50 liters/person/day. The lack of water consumption requires a water distribution system so that minimum water consumption can be met. Sumberrejo Village is one example that does not have a water distribution network, so to meet daily water needs using ground wells. The use of earthen wells certainly has risks, namely contamination from fecal waste. Research on water distribution network planning needs to be done due to these problems. This plan aims to determine the availability of water to flow through Sumberrejo Village, water needs in the projection year, pipe dimensions, and reservoir dimensions used. This study used a quantitative descriptive method. Hydraulic analysis of piping networks using the Hazen–William method with the Epanet 2.2 auxiliary program. The results of the study found that the availability of water in Sumberrejo Village was inadequate, so it used the Gedang Sutro water source located in Sumberwuluh Village. Water demand in the projection year is 20,966 l / s at peak hour conditions. The diameter of the pipe used in this planning is 8 inches; 6 inches; 5 inches; 4 inches; 3 inches; 2.5 inches; 2 inches; 1.5 inches; 1.25 inches; 1 inch; and 0.75 inches. The reservoir used in this planning is tubular with a diameter of 11.5 m and a height of 4.5 m.

EVALUASI KINERJA JARINGAN PIPA TRANSMISI MATA AIR PEBINI KECAMATAN KINTAMANI KABUPATEN BANGLI

The existing transmission pipeline network in Kintamani District, especially in the RV-II Reservoir in Catur Village to the RV-III Reservoir in Belantih Village, often experiences disruption due to leaks. The existing transmission pipe has a diameter of 12 inches and is of the Poly Vinyl Chloride (PVC) type. The current condition of the existing transmission pipe has been repaired several times due to leakage problems and the age of the pipe can be categorized as old. This research is to determine the condition of the existing transmission pipe network and find solutions to overcome problems in the leaking transmission pipe network. So that the water discharge pumped to RV-III Belantih Village can be maintained at 60 l/sec. Hydraulic analysis of pipe networks using the Epanet program. Based on primary data, the total pipe length from RV-II Catur Village to RV-III Belantih Village is 5,050 m. However, the plan to replace the existing transmission pipe is only 1,200 m long. Based on the results of the analysis of population growth in Catur Village and Belantih Village, the calculation results show that it is 0.0127% per year. The service distribution network to Catur Village and Belantih Village of 18.75 l/s is only able to meet the population's water needs until 2036. Simulation using the Epanet program, at nodes RP2.16 to RP2.40, the Ø10 inch PVC pipe design has a maximum pressure of 8,857 bar while the existing Ø12 inch PVC pipe has a maximum pressure of 9.3 bar. The simulated flow discharge for 24 hours is constant at 60 l/s resulting in a flow velocity of 1.22 m/s. Replacing pipes using Ø 10 inch PVC pipes is safer and more cost effective.

Analysis of Siphonic Roof Drainage Systems with EPANET

Analysis and design of siphonic roof drainage systems are usually performed with specific software developed by the system’s manufacturers. An experimental study was carried out to verify if a general software for the analysis of hydraulic pressurized pipe networks can be used to analyze a siphonic roof drainage system. A test model was built and tests were conducted to compare the prototype results with simulation runs in EPANET. A new EPANET data model was developed to overcome software limitations for the siphonic drainage systems analysis. Considering the results, less than 5% of average error was observed between the measures in the real test model and the simulation results, which can be attributed to measurement error. To validate the EPANET data model, it was compared with a specific software that analyzes siphonic roof drainage systems. It can be concluded that EPANET is a software that can be used to analyze and, therefore, to design, siphonic roof drainage systems in buildings.

A parallel computing architecture based on cellular automata for hydraulic analysis of water distribution networks

Water distribution networks (WDNs) are one of the largest infrastructures in society. Various methods for formulation and hydraulic analysis of water distribution networks, including numerical and non-numerical methods, have been previously proposed. Due to the complexity, the nonlinearity of the hydraulic equations of water distribution networks, and the need for multiple executions and uncertainties in parameters, solving the hydraulic model of water distribution networks has high time complexity. In this paper, a parallel computational architecture based on the concept of cellular automata is proposed to accelerate the numerical solution of the steady-state water distribution network model. Taylor series is proposed to solve hydraulic equations. The presented architecture was implemented as a parallel hardware platform on a field-programmable gate array. The performance of the proposed method was compared with EPANET software for networks with different complexities and topologies. The results show that the proposed parallel algorithm can accelerate the hydraulic analysis of regular water distribution networks up to 700 times and 250 times for small and large networks, respectively.

Elastic Water Column Model for Hydraulic Transient Analysis of Pipe Networks

Elastic Water Column Model for Hydraulic Transient Analysis of Pipe Networks

Influence of the thickness of the layer of internal deposits in pipelines of water supply and discharge systems on their remaining service life

Introduction. The practical operation of water supply networks, made of steel and gray cast iron, has proven that deposits accumulate on the inner surface of pipes under certain conditions. Deposition depends on the quality of transported water and the water flow regime, same as in gravity sewerage networks. A sediment layer accumulates in the flume of pipes if the actual flow rate is smaller than the minimum standard one. A layer of deposits in metal water pipes changes the value of the actual inner diameter of pipes and rises the pressure loss due to resistance along the pipeline length, which contributes to an increase in the energy consumption by the pumping equipment and affects the pressure value at the end point of a network. A layer of sediment in the flume of a gravity drainage network also rises losses along its length, slows down the flow rate and may block the water flow in the network. The purpose of the study is to find dependence between the remaining service life of water supply and sewerage networks, having internal deposits, and the thickness of the layer of deposits on pipe walls. Materials and methods. The authors use the dependences, that they have already derived for the hydraulic analysis of metal water supply networks and gravity sewerage networks, having internal deposits. Results. The authors have identified dependence between the remaining service life of water supply pipelines and sewerage systems and the thickness of deposits on the inner walls of pipes. Examples, confirming such a relationship, are provided. They are substantiated by graphs showing dependence between the remaining service life and the thickness of the layer of deposits in pipelines. A hydraulic criterion is proposed for projecting the term of operation of water supply and sewerage networks with internal deposits. Conclusions. The authors have proven the need to use special tables to analyze the characteristics of pipes within the framework of a hydraulic analysis of water supply and sewerage networks, having internal deposits.

Improvement of the performance of NSGA-II and MOPSO algorithms in multi-objective optimization of urban water distribution networks based on modification of decision space

Water distribution networks require huge investment for construction. Involved people, especially researchers, are always seeking to find a way for decreasing costs and achieving an efficient design. One of the main factors of the network design is the selection of proper diameters based on costs and deficit of flow pressure and velocity in the network. The reduction in construction costs is accomplished by minimizing the diameter of network pipes which leads to the pressure drop in the network. Supplying proper pressure in nodes is one of the important design principles, and low pressure will not provide a complete water supply at the consumption site. Therefore, in this research, the problem of optimization in several sample networks was defined with the objectives of cost minimization and minimization of pressure deficit in the whole network. The EPANET software was used for hydraulic analysis of sample networks, and the multi-objective optimization process was performed by coding NSGA-II and MOPSO algorithms in the MATLAB software environment and linking them to EPANET. The cost function was initially defined only by considering the relationship between cost and diameter and the length of pipes, and in the next definition, the cost resulted by violation of the allowable pressure range was added to this function In both cases, the schedule for achieving the optimal answer was executed. The results showed that these algorithms have a high ability to find optimal solutions and are able to optimize the network in terms of cost and pressure by finding the appropriate pipe diameter. The time for reaching convergence was reduced by considering the cost of violation of the allowable pressure limits significantly and the optimal answer is obtained in a small number of repetitions. In NSGA-II and MOPSO algorithms in two-looped network with 20 and 30 iterations and run time of 0.66 and 0.8 s, respectively, and in Lansey network with 150 and 250 iterations and run time of 5.7 and 9.5 s, the optimal solutions were obtained.

Justification of the need for the hydrodynamic cleaning of gravity water discharge networks

Introduction. It is widely known that the operation of sewage treatment facilities requires a significant amount of energy, consumed by the pumping equipment, the automated control system, lighting, heating, ventilation, etc. To ensure the reliable operation of pressure sewerage pipelines, it is necessary to analyze the flow parameters and adequately protect these structures from pressure surges (fluid shocks), that demonstrate unique features in the process of wastewater discharge. The proposed method of analyzing principal hydrodynamic parameters in case of a fluid shock takes into account the multi-phase nature of the pressure flow. The hydrodynamic cleaning of water supply and sewerage networks involves special equipment used to clean pipes, having the diameter of over 150 mm which are made of any material. The process of the hydrodynamic cleaning of networks is expensive and laborious. Therefore, the authors of the article propose to prepare a preliminary justification report for such an expensive operation. The purpose of the research is to identify the pipe characteristics, that can justify the application of the hydraulic method for the removal of a layer of internal deposits. Materials and methods. Dependencies, derived by the authors for the purpose of the hydraulic analysis of gravity drainage networks, are used in the article. Results. Dependence between the actual pipe filling and the thickness of the sediment layer in the pipe gully was confirmed. A specific example is provided by the authors to confirm the existence of such a dependence. The graph shows dependence between the actual pipe filling level and the thickness of the sediment layer in the gully and dependence between the value of the hydraulic slope and the thickness of the actual sediment layer. Conclusions. It is shown that the hydrodynamic cleaning of pipes, having a gully sediment layer exceeding 70 mm, is justified for the case analyzed in the article.

Evaluation of service pressure regulation strategy on the performance of a rural water network based on pulse demand; using the method of characteristics

Abstract Reducing the occurrence of pipe bursts, reducing leakage, and reducing energy consumption are the three main goals in implementing pressure control programs in water distribution networks. Service pressure regulation strategy is an evolved approach that encompasses all goals of pressure management. This paper has investigated this approach in a rural network with hydraulic complexities as a case study so that some parts of the network have excess pressure and other low pressure. A computer code based on the method of characteristics (MOC) has been developed for network hydraulic analysis. The generated code analyzes unsteady flow, pressure-driven demand analysis, and dynamic adjustment of pressure control valves based on the target node. Also, the experimental results of a laboratory network have been applied to validate and calibrate the numerical simulation. In addition, by measuring the flow rate and pressure of the network and the results of the minimum night flow method, three consumption patterns were used to generate pulsed nodal demands. Studies show that creating pressure-management areas by hydraulic analysis by MOC will determine the best control strategies. The mean pressure decreased 54% by applying this strategy. Furthermore, the average fluctuations of pressure reduced from 9.7 meters to 3.5 meters.

Discussion of “Hydraulic Analysis of Intermittent Water-Distribution Networks Considering Partial-Flow Regimes” by S. Mohan and G. R. Abhijith

Discussion of “Hydraulic Analysis of Intermittent Water-Distribution Networks Considering Partial-Flow Regimes” by S. Mohan and G. R. Abhijith

Closure to “Hydraulic Analysis of Intermittent Water-Distribution Networks Considering Partial-Flow Regimes” by S. Mohan and G. R. Abhijith

Closure to “Hydraulic Analysis of Intermittent Water-Distribution Networks Considering Partial-Flow Regimes” by S. Mohan and G. R. Abhijith

Discussion of “Hydraulic Analysis of Intermittent Water-Distribution Networks Considering Partial-Flow Regimes” by S. Mohan and G. R. Abhijith

Discussion of “Hydraulic Analysis of Intermittent Water-Distribution Networks Considering Partial-Flow Regimes” by S. Mohan and G. R. Abhijith

Smart Water Grid Research Group Project: An Introduction to the Smart Water Grid Living-Lab Demonstrative Operation in YeongJong Island, Korea

In South Korea, in line with the increasing need for a reliable water supply following the continuous increase in water demand, the Smart Water Grid Research Group (SWGRG) was officially launched in 2012. With the vision of providing water welfare at a national level, SWGRG incorporated Information and Communications Technology in its water resource management, and built a living lab for the demonstrative operation of the Smart Water Grid (SWG). The living lab was built in Block 112 of YeongJong Island, Incheon, South Korea (area of 17.4 km2, population of 8000), where Incheon International Airport, a hub for Northeast Asia, is located. In this location, water is supplied through a single submarine pipeline, making the location optimal for responses to water crises and the construction of a water supply system during emergencies. From 2017 to 2019, ultrasonic wave type smart water meters and IEEE 802.15.4 Advanced Metering Infrastructure (AMI) networks were installed at 527 sites of 958 consumer areas in the living lab. Therefore, this study introduces the development of SWG core element technologies (Intelligent water source management and distribution system, Smart water distribution network planning/control/operation strategy establishment, AMI network and device development, Integrated management of bi-directional smart water information), and operation solutions (Smart water statistics information, Real-time demand-supply analysis, Decision support system, Real-time hydraulic pipeline network analysis, Smart DB management, and Water information mobile application) through a field operation and testing in the living lab.

Physical controls in the simulation of hydraulic networks in buildings using Epanet 2.0 software

Water supply and distribution are an important design criterion in building construction. For this it is necessary to make an analysis of hydraulic networks, which is generally done through conventional methods based on iterative processes in spreadsheets. However, the Epanet 2.0 software can serve as an analysis method through simulation that is not currently considered for these applications, while such software is not a conventional method, it holds the possibility of being a model which through physical controls can serve as a simulator for hydraulic networks with the hypothesis that it can optimize costs and solution times. Therefore, the research has as purpose the application of physical controls for the analysis of the hydraulic networks in buildings by means of the software. For this reason, a design of the hydraulic network calculated by the modified Hunter model was executed and compared with the simulation in the software. The results obtained from the study demonstrated effectiveness of the software with a minimum percentage of error (0.24% to 1.06%) from one method to another, achieving to optimize calculation times and the economy of designs.

Hydraulic Analysis of Intermittent Water-Distribution Networks Considering Partial-Flow Regimes

AbstractModeling intermittent water distribution networks (WDNs) requires effective incorporation of the transient flow conditions, including the transitions from pressurized to partial flow regime...

Seismic reliability analysis of water distribution networks on the basis of the probability density evolution method

In this study, a new approach for assessing the seismic functional reliability of water distribution networks is presented on the basis of the probability density evolution method. The original contribution of this paper is to build a new framework for the reliability analysis of water distribution networks on the basis of the physical mechanism of water distribution networks subjected to earthquakes. Firstly, a finite element model is established to capture the seismic response of the entire buried pipe networks. Then the nodal head of water distribution networks is derived through hydraulic analysis of water distribution networks with leakages. Secondly, owing to the randomness of ground motions, the probability density functions of the nodal heads of water distribution networks are obtained on the basis of the probability density evolution method. Thirdly, the seismic functional reliability of water distribution networks is evaluated considering the demand heads of nodes. When the nodal head is larger than the predetermined water head, the node is reliable while when the nodal head is smaller than the predetermined water head, the node is not reliable. Two examples, namely, a virtual and an actual water distribution networks, are examined in detail to investigate the feasibility of the proposed method. Results show that the proposed method effectively evaluates the seismic functional reliability of water distribution networks.

A method of analysis of complex hydraulic networks

A simple and reliable iterative solution method of classical hydraulic network flow rate distribution problem is described. The method is based on chord linearization of inverse branch loss function which keeps basic branch properties. It has good speed of convergency which is practically independent of initial values.

Effectiveness of Several Metaheuristic Methods to Analyze Hydraulic Parameters in a Drinking Water Distribution Network

The reliability and ease of applying metaheuristic methods in solving large and complex equation systems make it interesting to be applied as an alternative solution to solving problems in various fields. This article proves the effectiveness of an optimization model based on the metaheuristic method for the analysis of hydraulic parameters of drinking water distribution pipes. The metaheuristic methods explored are Differential Evolution (DE) algorithm, Particle Swam Optimization (PSO) algorithm and CODEQ algorithm. The effectiveness of the three methods is measured relative by comparing the results of the analysis of the three models with the results from Newton Raphson method and Monte Carlo simulation method. The analysis shows that the optimization model based on the DE, PSO and CODEQ algorithms is very effective for solving problems on a simple network that has 6 pipe elements and 5 service nodes. The results obtained have a level of accuracy as good as Newton Raphson method. In the case of complex networks that have 32 pipe elements and 21 service nodes, there is an indication of performance degradation which is indicated by a decrease in fitness value. In this case, Newton Raphson method still shows its consistency. The optimization model based on the metaheuristic method is still far more effective than the Monte Carlo simulation method, although it is not as effective as Newton Raphson method. The Monte Carlo simulation method is not recommended for hydraulic pipe network analysis, even for simple networks.