Pipe Network Optimization Research Articles

Operation Optimization of Natural Gas Pipe Network Considering Energy Metering

Operation Optimization of Natural Gas Pipe Network Considering Energy Metering

Optimization of Water Pipe Network and Formulation of Pumping Rate

Minimizing water delivery costs and increasing water supply dependability are the two key objectives in designing and operating of water distribution systems. An analytical solution for the best pipe diameters of a water distribution pipe network was created in this study. The raw water was collected from a water canal and transported to a treatment plant (WTP). The cleansed water was pushed into the water distribution network via the pumping station. The derivative approach was used in the optimization process, and the cost functions incorporating the various capital and operating expenses were used. The initial diameters were adjusted to reach the least-cost diameters. The study shows that the optimum design of a pipe network (PNW) achieves saving a total cost of about 12.3% after utilizing our unique method. The optimal pumping rate in the PNW can also be determined using an analytical approach that considers the optimum value that occurs when the minor and friction losses in the entire network are at their lowest. The analytical solution for the optimum pumping rate shows a rigid value of optimum pumping rate (Qopt) which is 5296.32 m3/day. On comparative estimates, this figure is very close to that of 5,300 m3/day interpreted from the graphical solution, with negligible deviation. The total cost and optimum pumping rate results for the analyzed PNW example demonstrate the correctness of the analytical solutions, reliability, and dependability of the assumptions.

Discussion of “Seismic Rehabilitation Optimization of Water Pipe Networks Considering Spatial Variabilities of Demand Criticalities and Seismic Ground Motion Intensities” by Binaya Pudasaini and Mohsen Shahandashti

Discussion of “Seismic Rehabilitation Optimization of Water Pipe Networks Considering Spatial Variabilities of Demand Criticalities and Seismic Ground Motion Intensities” by Binaya Pudasaini and Mohsen Shahandashti

Synchronization Optimization of Pipe Diameter and Operation Frequency in a Pressurized Irrigation Network Based on the Genetic Algorithm

The pressurized irrigation network aims to deliver water to consumption nodes at an appropriate pressure and discharge. The traditional pipe network optimization minimizes the annual operating cost or investment per unit area. The present work establishes the traditional pipe diameter and operating frequency optimization models based on flattish terrain. It proposes a new synchronization optimization method of pipe diameter and operation frequency to find the best match point for pipe diameter and operating frequency in the branched network system. The irrigation costs of the above three models, including the energy and pipe network costs, are compared with the original irrigation network system. Based on the results of optimizing the typical experimental field, the operation frequency optimization model and the pipe diameter optimization model can save about 1.4% and 10.6% in irrigation cost, respectively. Furthermore, the synchronous optimization model can significantly reduce the irrigation cost to about 19.3%, including a 26.6% reduction in the pipe network cost and a 21.9% increase in the energy cost. Compared with pipe diameter optimization, synchronous optimization can further reduce network costs while generating lower energy costs. The results of this research can be used for the design of the network system in flattish terrain to reduce the irrigation cost.

Optimal Design of Water Supply Network Based on Adaptive Penalty Function and Improved Genetic Algorithm

In view of the shortcomings of water supply network optimization design based on the traditional genetic algorithm in water supply safety and economy, an improved crossover operator adaptive algorithm and penalty function are proposed to improve the traditional genetic algorithm, which can effectively solve the problem of local optimal solution caused by too early convergence of the traditional genetic algorithm in pipe network optimization design. Taking a typical annular water supply network as an example, the calculation results show that the economy of the design scheme of the improved genetic algorithm is better than the traditional genetic algorithm, which fully shows that the improved genetic algorithm is practical and effective for the optimal design of water supply network.

Study on Construction Resource Optimization and Uncertain Risk of Urban Sewage Pipe Network

With considering sewage pipe network upgrading projects in the “villages” in cities, the optimization of construction resources and the assessment of delay risks could be achieved. Based on the schedule-cost hypothetical theory, the mathematical model with constraint indicators was established to obtain the expression of optimal resource input, and conclude the method to analyze the schedule uncertainties. The analysis showed that cyclical footage of pipe could be regarded as a relatively fixed value, and the cost can be regarded as a function that depending on the number of working teams. The optimal number of teams and the optimal schedule occurred when the minimum total cost achieved. In the case of insufficient meteorological data, the Monte Carlo simulation method and uncertainty analysis method can be applied to assess the impact of rainfall on the total construction period, correspondingly the probability of such risk could be derived. The calculation showed that the risk of overdue completion varied significantly according to the construction starting time. It was necessary to take rainfall risk into consideration and make corresponding strategies and measures.

Seismic Rehabilitation Optimization of Water Pipe Networks Considering Spatial Variabilities of Demand Criticalities and Seismic Ground Motion Intensities

AbstractOperation of critical infrastructure facilities such as hospitals, firefighting stations, and disaster shelters are critical during a postearthquake scenario. The serviceability of many suc...

Research and practice on optimal design method of the oilfield water injection system pipeline network

The efficiency of oilfield water injection system is generally low and energy consumption is high. With the deepening of oilfield exploitation, the water cut of the oilfield is increasing, the power consumption of the water injection system is increasing year by year, the oilfield exploitation cost is increasing, and energy conservation and consumption reduction are very important. In order to improve oilfield water injection efficiency and reduce water injection energy loss, this paper puts forward the pipe network optimization design method of partial pressure water injection, establishes the mathematical model of partial pressure water injection pipe network and throttling loss calculation model, compiles the calculation software of partial pressure water injection mathematical model, optimizes the partial pressure interval, calculates the partial pressure points, effectively reduces the energy loss of water injection system and improves the efficiency of water injection system.

Optimal diameter of district heating pipe network based on the hybrid operation of distributed variable speed pumps and regulating valves

The district heating system that uses the hybrid operation of distributed variable speed pumps and regulating valves can effectively reduce the pressure level at the far-end of the heating network, while retaining the energy saving advantages of the distributed variable speed pump system and ensuring the safe operation of the heating network. In this study, pipe network optimization based on genetic algorithm was used to determine the pipe diameter required for the hybrid operation of distributed variable speed pumps and regulating valves. A mathematical model was established to evaluate the economic efficacy based on the annual equivalent cost. The zero-pressure difference point was evaluated to optimize the pipe diameter. A real pipe network was assessed to evaluate the efficacy of the method, and a sensitivity analysis of pressure constraints and economic factors was conducted. Our results show the system of hybrid operation of distributed variable speed pumps and regulating valves can reduce the annual equivalent cost by about 10.35% compared to the conventional central circulating pump system. In addition, the annual energy consumption due to heat loss and pump operation is only 0.36% higher than that of the conventional central circulating pump system.

Energy stations and pipe network collaborative planning of integrated energy system based on load complementary characteristics

Abstract In view of the lack of effective energy station site optimization method in the existing integrated energy system (IES) planning, and the failure to consider the load characteristics in the division process of the energy supply area of energy stations, a collaborative planning method of energy stations and pipe networks considering the complementary load characteristics is proposed. Firstly, based on the analysis of the interaction between the station and network planning of IES, an alternated optimal method framework of energy station site, energy supply area division and pipe network layout are proposed. Secondly, based on the energy supply radius of the energy station, this paper proposes a method to determine the number of new energy stations, and based on the topological characteristics of the cellular networks, a method of determining the initial energy station site is proposed. Thirdly, considering the complementary load characteristics, the evaluation index and division method of energy supply area of integrated energy station are proposed. Fourthly, aiming at the problem of pipe network layout on the road, a pipe network optimization method based on Kruskal algorithm is proposed, and optimizes the direction of load access to the pipe network by the linear optimization model. Fifthly, the calculation method of equivalent energy distance of load and the optimization method of energy station site based on equivalent energy distance are proposed. Finally, the rationality and effectiveness of this method are verified by an example.

Topological surrogates for computationally efficient seismic robustness optimization of water pipe networks

AbstractThe criticality of seismic robustness of the water pipe networks cannot be overstated. Current methodologies for optimizing seismic robustness of city‐scale water pipe networks are scarce. A very few studies that can be found are also prone to long optimization runtimes due to the requirement of repeated hydraulic analysis. Hence, there is a critical need for the identification of computationally efficient surrogate optimization methods for maximizing seismic robustness of water pipe networks. To address this need, this research was conducted to identify, for the first time, computationally efficient topological surrogates for hydraulic simulation‐based optimization. The computational efficiency of surrogate optimization was measured in terms of solution quality (i.e., post‐earthquake serviceability) and computational runtime. Ten different topological connectivity metrics were evaluated out of which five were considered computationally infeasible due to their prohibitive optimization runtime. Five remaining metrics were then used to formulate five surrogate objective functions for seismic robustness of water pipe networks. Each of these functions was optimized using a simulated annealing‐based algorithm. Application of the proposed approach to city‐level benchmark networks helped to identify two metrics out of ten that offered a substantial reduction in optimization runtime with a minimal loss in solution quality. These findings will be highly valuable to water distribution network managers for identifying economical rehabilitation policies for enhancing the seismic robustness at a city‐scale within a reasonable amount of time.

CFD-Based Optimization of Hot Primary-Air Pipe Networks in Power Plant Milling Systems

A hot primary-air pipe system is the bridge connecting an air-preheater with a coal mill in power generation stations. The effective geometrical configuration of the pipe network greatly affects the air flow distribution and consequently influences the safe and economic operation of milling systems in power stations. In order to improve the properties of the air flow, in the present work the SIMPLEC method is used to simulate numerically the flow field for the original layout of the system. As a result, the internal mechanisms influencing the uneven pressure drop in each branch are explored and three optimization schemes are proposed accordingly. The numerical results indicate that, for the original layout, the local pressure drop of the tee section accounts for approximately 74% of the total drop of the system, with other pressure drops depending on the specific branch considered. It is shown that after optimization, a roughly balanced flow resistance and flow rate can be obtained. Compared with the original layout, the pressure drop relating to different branches is significantly reduced.

Pipeline Network Layout Design of Integrated Energy System based on Energy Station Site Selection and Load Complementary Characteristics

In view of the lack of effective energy station site optimization method in the existing integrated energy system (IES) planning, and the failure to consider the load characteristics in the division process of the energy supply area of energy stations, a pipeline network layout method of integrated energy system is proposed based on energy station site selection and load complementary characteristics. Firstly, based on the analysis of the interaction between the station and network planning of IES, an alternated optimal method framework of energy station site, energy supply area division and pipe network layout are proposed. Secondly, based on the energy supply radius of the energy station, this paper proposes a method to determine the number of new energy stations, and based on the topological characteristics of the cellular networks, a method of determine the initial energy station site is proposed. Thirdly, considering the complementary load characteristics, the evaluation index and division method of energy supply area of integrated energy station are proposed. Fourthly, aiming at the problem of pipe network layout on the road, a pipe network optimization method based on Kruskal algorithm is proposed, and optimize the direction of load access to the pipe network by the linear optimization model. Fifthly, the calculation method of equivalent energy distance of load and the optimization method of energy station site based on equivalent energy distance are proposed. Finally, the rationality and effectiveness of this method are verified by an example.

An area-wide layout design method considering piecewise steam piping and energy loss

Pipeline layout is a significant factor influencing an area-wide layout. But in the most of published works, piping system only consists of the one-to-one connection pipelines with constant diameters. In addition, energy loss is sometime ignored in previous works. In this work, energy loss due to pressure loss and heat loss is taken into consideration originally. An improved method is proposed to design an industrial area-wide layout considering the optimization of pipe network. The pipe length of steam piping is optimized based on Kruskal algorithm. The diameters of steam piping are piecewise considered. The flow rates are obtained by solving a linear programming (LP) model. The problem of area-wide layout optimization is solved by genetic algorithm (GA). Finally, the results of a case study show that the optimization of piecewise steam piping can reduce the total flow rate and energy loss of all branches in the pipe network.

Transient Modeling and Simulation of Gas Pipe Networks with Characteristic Diagram Models for Compressors

AbstractOne challenge for the simulation and optimization of real gas pipe networks is the treatment of compressors. Their behavior is usually described by characteristic diagrams reflecting the connection of the volumetric flow and the enthalpy change or shaft torque. Such models are commonly used for an optimal control of compressors and compressor stations [4,7] using stationary models for the gas flow through the pipes. For transient simulations of gas networks, simplified compressor models have been studied in [1–3]. Here, we present a transient simulation of gas pipe networks with characteristic diagram models of compressors using a stable network formulation as (partial) differential‐algebraic system. (© 2017 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Resilience-based optimal design of water distribution network

Optimal design of water distribution network is generally aimed to minimize the capital cost of the investments on tanks, pipes, pumps, and other appurtenances. Minimizing the cost of pipes is usually considered as a prime objective as its proportion in capital cost of the water distribution system project is very high. However, minimizing the capital cost of the pipeline alone may result in economical network configuration, but it may not be a promising solution in terms of resilience point of view. Resilience of the water distribution network has been considered as one of the popular surrogate measures to address ability of network to withstand failure scenarios. To improve the resiliency of the network, the pipe network optimization can be performed with two objectives, namely minimizing the capital cost as first objective and maximizing resilience measure of the configuration as secondary objective. In the present work, these two objectives are combined as single objective and optimization problem is solved by differential evolution technique. The paper illustrates the procedure for normalizing the objective functions having distinct metrics. Two of the existing resilience indices and power efficiency are considered for optimal design of water distribution network. The proposed normalized objective function is found to be efficient under weighted method of handling multi-objective water distribution design problem. The numerical results of the design indicate the importance of sizing pipe telescopically along shortest path of flow to have enhanced resiliency indices.

Using ATP tests for assessment of hygiene risks

Abstract Adenosine-5’-triphosphate (ATP) is a high-energy molecule playing a role of universal energy carrier used in cell metabolism. Since ATP is present in both prokaryotic and eukaryotic cells, this coenzyme can be used to determine a hygiene state. During last decade there has been a significant growth of practical applications of ATP measurements. ATP tests are commonly used for an assessment of hygienic conditions in food industry, residential buildings and hotels. In comparison with traditional and time-consuming laborious microbial analysis the measurement of ATP provides a quick indicative on-site data, characterizing microbial and organic contamination to support decision-making with regards to adequate corrective and preventive actions. This paper demonstrates applications of ATP in practice and, particularly, in water treatment technology and wastewater processing. The review highlights opportunities for using the test for the optimization of water treatment facilities and pipe networks functioning in order to assess wastewater toxicity and wastewater treatment process efficiency. Other areas of application are also addressed. The review of literature indicates that ATP used in different areas of industry can be considered as a diagnostic method - complement the classical methods - useful for identification of hygiene risks as well as a tool for a real-time management of health and environmental risks.

A Graph Portioning Approach for Hydraulic Analysis-Design of Looped Pipe Networks

This study introduces a new formulation for hydraulic analysis and design of looped pipe networks. The network is partitioned into two sub-graphs so-called the base and the remainders graphs. The base graph is a spanning tree of the network and, the remainders graph includes pipes hypothetically removed from the network to open the loops. The network governing equations of mass and energy conservation are manipulated so that, pipe flows in the remainders and head losses in the base graph are considered as independent variables to calculate pipe diameters directly. The method is applied to two example networks and the results are discussed. The new approach is found to be computationally efficient and useful for design and optimization of pipe networks.

Study on Management System of Drainage Network

The advanced intelligent optimization algorithms used in water distribution network model study, currently in the pipe network optimization theory is a new, has great research value and practical value of the subject. This paper proposes a decision-making functions to optimize the drainage network system, by choosing the model using intelligent optimization algorithm for computing the most cost-caliber combination, to achieve the renovation and expansion of urban water supply network technical support.

The Steam Pipe Network Mathematical Modeling and Flow Field Analysis of Zibo Power Plant

As Zibo power plant original steam pipes for a long time to run, the strength decreased and resistance was large, transformation was proposed to optimize. A mathematical model of the main steam pipe network was established to analysis changes of temperature, pressure and velocity vector before and after transformation. After transformation, the loss was significantly reduced,so transformation successfully achieve the optimization, adjustment and analysis functions of the main steam pipe network.