Distribution Pipes Research Articles

Returning Individual Tap Water Testing Results to Research Study Participants after a Wildfire Disaster.

After the devastating wildfire that destroyed most of the town of Paradise, California in 2018, volatile organic compounds were found in water distribution pipes. Approximately 11 months after the fire, we collected tap water samples from 136 homes that were still standing and tested for over 100 chemicals. Each participant received a customized report showing the laboratory findings from their sample. Our goal was to communicate individual water results and chemical information rapidly in a way that was understandable, scientifically accurate, and useful to participants. On the basis of this process, we developed a framework to illustrate considerations and priorities that draw from best practices of previous environmental results return research and crisis communication, while also addressing challenges specific to the disaster context. We also conducted a follow-up survey on participants’ perceptions of the results return process. In general, participants found the results return communications to be understandable, and they felt less worried about their drinking water quality after receiving the information. Over one-third of the participants reported taking some kind of action around their water usage habits after receiving their results. Communication with participants is a critical element of environmental disaster research, and it is important to have a strategy to communicate results that achieves the goals of timeliness, clarity, and scientific accuracy, ultimately empowering people toward actions that can reduce exposure.

Direct evidence of microbiological water quality changes on bacterial quantity and community caused by plumbing system

Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compared the water quality in the water main and at customer tap by preparing a sampling tap on the water main. The biomass was quantified by adenosine triphosphate (ATP) and the microbial community was profiled by 454 pyrosequencing. The results showed that in distribution pipes, biofilm contributed >94% of the total biomass, while loose deposits showed little contribution (< 2%) because of the low amount of loose deposits. The distribution of biological stable water had minor effects on the microbiocidal water quality regarding both quantity (ATP 1 ng/L vs. 1.7 ng/L) and community of the bacteria. Whereas the plumbing system has significant contribution to the increase of active biomass (1.7 ng/L vs. 2.9 ng/L) and the changes of bacterial community. The relative abundance of Sphingomonas spp. at tap (22%) was higher than that at water main (2%), while the relative abundance of Pseudomonas spp. in tap water (15%) was lower than that in the water from street water main (29%). Though only one location was prepared and studied, the present study showed that the protocol of making sampling tap on water main offered directly evidences about the impacts of plumbing system on tap water quality, which makes it possible to distinguish and study the processes in distribution system and plumbing system separately.

Water Leakage Detection System Using Arduino

Clean water is a scarce resource for the human life and is subject to wastage due to leakage of the distribution pipes in large cities. Water pipe leakage is a big problem around the world of which most of the water distribution authorities faces difficulties to detect the location of the fault. This problem of leakage can be caused by several factors such as breakage of the pipelines due to aging or ongoing constructions in urban cities like Dar es salaam, consequently due to that case, the distribution authorities face hardship to identify the cause and enable them to take action. Therefore, the aim of this project was to develop an IoT-based system for water leakage detection. The prototype was developed comprising two sensors embedded at the source and destination points to measure the flow rate of water. The result indicated that the volume of water generated at the start point can be compared with the other end to determine if there is any leakage. A greater focus on distance calculation could produce interesting findings that account for more research on IoT monitoring systems.

Analysis of water distribution systems and head losses using the hardy-cross method

Distribution services have not been running optimally at PDAM Tirta Meulaboh, that This study aims to determine the level of pressure loss in the PDAM’s clean water pipe network. The method used in this research is a quantitative descriptive survey method supported by primary data and secondary data. Calculation of the amount of pressure loss using the hardy cross method. The results showed that the observed value of discharge with the highest water consumption was at 18:00 WIB at 0.172 m3 / person, while for the lowest use was at 14:00 WIB at 0.119 m3 / person. It can be concluded that this time is the peak time for water consumption. High-pressure water where the maximum average is 0.00000599 m, because high pressure is not adequate. The maximum loss of high pressure is found in the loop (VII) of 2.57025 m or 0.257025 atm, for the minimum pressure there is in the loop (VI) of - 0.00024 m or -0.000024 atm. It is necessary to re-evaluate the distribution network system by PDAM such as surveys to find out the causes of high water pressure losses to customers such as surveys for water leaks in distribution pipes, replacing old pipes.

Image Reconstruction for ECT under Compressed Sensing Framework Based on an Overcomplete Dictionary

Electrical capacitance tomography (ECT) has great application potential in multiphase process monitoring, and its visualization results are of great significance for studying the changes in two-phase flow in closed environments. In this paper, compressed sensing (CS) theory based on dictionary learning is introduced to the inverse problem of ECT, and the K-SVD algorithm is used to learn the overcomplete dictionary to establish a nonlinear mapping between observed capacitance and sparse space. Because the trained overcomplete dictionary has the property to match few features of interest in the reconstructed image of ECT, it is not necessary to rely on the sparsity of coefficient vector to solve the nonlinear mapping as most algorithms based on CS theory. Two-phase flow distribution in a cylindrical pipe was modeled and simulated, and three variations without sparse constraint based on Landweber, Tikhonov, and Newton-Raphson algorithms were used to rapidly reconstruct a 2-D image.

A Data-driven Model of Pipe Diameter and Insulation Thickness Optimization for District Heating Systems

One of the major downsides of district heating systems is the large thermal loss through the distribution pipe network, which is expected to be alleviated through the optimization for the thickness of the insulation layer and the pipe diameter. Although a few previous studies have developed a diversity of techno-economic models for optimizing the pipe diameter or the insulation thickness of the district heating pipeline, few of them were able to capture the complicated relationship among the heat loss, pipe diameter, insulation thickness, operation parameters, and complex exterior conditions in the real world (such as the conditions of the soil and degradation condition of the insulation layer). The present study devises a combined model that first bases on the heat transfer model to theoretically estimate heat losses and then bases on the data-driven artificial-neural-network model to fill in the gap between the measured and theoretical heat losses. Results show that the predicted heat losses via the developed combined model reproduce the measured data well. Furthermore, compared with the original pipe diameter and insulation layer thickness, the optimized diameters of the pipe and thickness values of the insulation layers via the proposed combined model are all elevated.

Experimental Investigation of Two-Phase Flow Maldistribution in Plate Heat Exchangers

After conducting a critical survey of the different categories of existing heat exchangers, the results of several experiments about the behaviour of a two-phase current in an open channel are reported. The results confirm the complexity of the problems induced in heat exchangers by flow maldistribution, especially when two-phase flows are considered in multi-channel systems. It is shown that severe misalignment of heat exchangers can lead to a loss of economic performance of more than 25%. Improper distribution of fluid flow causes longer fluid coils to form, and the liquid cochlea can eventually occupy a large space, thereby reducing heat transfer and disrupting the considered biphasic system. The use of a small diameter distribution pipe with properly spaced outlet holes seems to be a promising approach to fix many of these issues. It is found that the current distribution in the channels, in addition to the header pressure distribution, also depends on factors such as the geometry and the initial flow regime in the header.

An ILP-Assisted Two-Stage Layout Optimization Method for Satellite Payload Placement

In the satellite overall design phase, it is a crucial step to perform satellite layout design to guarantee that the aggregation of electronic components can operate normally and stably in an appropriate temperature environment. In order to handle the satellite payload placement problem of the DongFangHong 4 (DFH-4) platform, the heat pipe-constrained component layout optimization (HCLO) problem is proposed with the HCLO model formulated. Through careful investigation, it can be divided into two optimization subproblems that can be solved subsequently. Based on the divide-and-conquer strategy, an integer linear programming- (ILP-) assisted two-stage layout optimization method is proposed. In stage one, component-heat pipe distribution optimization is performed using the ILP technique so that specific heat pipes occupied by each component can be determined and the horizontal movement range of components can be reduced. In stage two, the detailed component layout optimization is investigated to obtain the final positions of components. First, the sequence layout sampling (SeqLS) method is used to generate one nonoverlap initial layout. Next, swap operation between components is incorporated to reduce the centroid deviation. Finally, sequential quadratic programming (SQP) search is conducted based on the generated promising initial layout solutions. Therefore, the SeqLS-based heuristic layout search algorithm is proposed in the second stage. Two layout test cases, including 15 components and 90 components, respectively, are investigated to demonstrate the validity and efficacy of the proposed layout design method. Experimental results show that it is promising to apply such a two-stage approach for satellite payload placement in engineering.

Optimizing access to drinking water in remote areas. Application to Nepal

This study is motivated by the need to restore part of the Nepal water distribution network that was destroyed by the Gorkha and Dolakha earthquakes in April and May 2015. The problem consists of two hierarchical subproblems: locating water taps to ensure a good coverage of the population, and connecting these water taps to water sources by means of a pipe distribution network. Both subproblems are subject to a variety of accessibility and technical constraints that make the problem unique and highly complex. Namely, because Nepal is highly mountainous, elevations must be taken into account in the distance calculations, and the distribution network is gravity-fed, meaning that pumps are not used. The problem is solved by means of a two-phase matheuristic: the first subproblem is a constrained location–allocation problem which is solved exactly by integer linear programming, while the second subproblem is tackled by means of a cluster-first, tree-second heuristic. Several variants of the heuristic are developed and compared. The network design problem is of very large scale, being solved on a graph with as many as 29,900 vertices and 75,200 arcs. Tests are performed on real-world data, obtained by satellite imagery, from the Suspa Kshemawati and Lapilang communities in the Dolakha district. Extensive computational results confirm the effectiveness of the proposed methodology and enable an identification of the best parameter settings and algorithmic tactical choices.

Gene expression programming based mathematical modeling for leak detection of water distribution networks

Globally, the loss of potable water through buried and service water distribution networks (WDNs) is one of the persistent challenges confronted by water utilities. Most of the WDNs inspection methods are ad-hoc and typically provide the current status of the pipes. Despite the significant research efforts, a reliable prediction method of the water leak of buried and service water distribution pipes is rare. To overcome this challenge, gene expression programming (GEP) models – that uses extracted features of acoustic signals collected from noise loggers attached to pipeline valves at the chamber – are developed and validated in the current study. To develop these models, extensive fieldwork hitherto unavailable was undertaken in this study to record the flow-induced acoustic signal of WDNs. The GEP models are developed using a step function – that returns a binary output – which is leveraged to exhibit the proposed detection and prediction methods using the acoustic signal collected from the buried WDNs. The models only consider the highly correlated features with the leakage. The models are found to be able to predict leakages on metal and nonmetal pipes with about 95% accuracy. These models were developed to reduce the time and cost of deployment of equipment for leakage detection of pipes. The proposed method presented in this study highlights the prospect and advantage of using the GEP in infrastructural management given the amazing capability of the machine intelligence technique to recognize multi-dimensional circumstances with ease, high prediction accuracy, and potential for unceasing improvement.

Air-to-water heat pumps: Review and analysis of the performance gap between in-use and product rated performance

Air-to-water heat pumps are regarded as a fundamental part of many proposed climate action plans in heating dominated climates. However, individual studies have concluded that this technology generally underperforms in practice when compared to its rated performance. This study aims to harmonise these conclusions and propose reasons for this reported underperformance. The European standards used to rate the performance of heat pumps are first reviewed and deconstructed, a review and analysis of all past research that report air-to-water heat pump performance is then conducted. Finally, a novel in-situ monitoring study of an air-to-water heat pump in Ireland is presented. Of the 378 heat pumps reviewed, it was found that the average seasonal performance was 2.59, significantly lower than typical product rated performances. Three reasons for this underperformance include, misrepresentative weather data for certain locations, unaccounted for losses in the distribution pipes and unaccounted for effects of cycling. The measured seasonal performance factor of the case study heat pump monitored in this paper was 2.49 for space heating. This 40% reduction in performance, when compared to the product rated performance of 4.12, was attributed to the three reasons identified. Because these reasons are largely due to inadequate installation practice, environmental policy should focus not just on the quantity of these technologies to be installed but critically also on the quality of the installation itself.

Structural simulation analysis of high pressure common rail pipe

As one of the key components of the common rail system, the accuracy of pressure field and velocity field analysis of the common rail pipe is related to the service reliability. In order to obtain the velocity and pressure distribution that difficult to be measured in the experiment, this paper considers using three-dimensional modeling and establishing the three-dimensional model of oil flow in the common rail pipe based on the fluid simulation software, and then obtains the velocity field and pressure field distribution of the common rail pipe through numerical simulation. The cone angle at the nozzle structure of common rail pipe is compared and analyzed. Meanwhile the most appropriate cone angle’s processing angle among the commonly used processing cone angles is obtained, which improves the rationality of common rail pipe structure processing. It is great significance to the subsequent rail pressure stabilization analysis of common rail pipe.

Spatio-temporal patterns of domestic water distribution, consumption and sufficiency: Neighbourhood inequalities in Nairobi, Kenya

Whilst there are longstanding and well-established inequalities in safe-drinking water-access between urban and rural areas, there remain few studies of changing intra-urban inequalities over time. In this study, we determined the spatio-temporal patterns of domestic piped water distribution in Nairobi, Kenya between 1985 and 2018, and the implications of socio-economic and neighbourhood inequalities in water sufficiency. Using data from the Nairobi water and sewerage utility company for the period 2008–2018, we examined the sufficiency of monthly domestic water consumption per capita for 2380 itineraries (areas with an average population of 700) in relation to a residential neighbourhood classification, population and neighbourhood age and also examined water rationing patterns by neighbourhood type. Water sufficiency differed by residential areas, age of neighbourhood and population per itinerary. Compared to residents of low-income areas, those in high- and middle-income areas were six and four times more likely to receive the recommended 1500 L per capita per month respectively. Newer neighbourhoods and less densely populated areas were more likely to receive higher volumes of water. Non-revenue water loss accounted for 29% (average 3.5 billion litres per month) of water distributed across Nairobi, and was more than two times the amount of water needed for all residents to access the recommended monthly per capita water consumption. The observed spatial inequality in distribution, and access to piped water associated with socio-economic status and neighbourhood age highlights the need for deliberate planning and governance to improve water distribution to match the speed of growth of low/middle- and low-income residential areas and enhance equity.

Phononic Band Gap and Free Vibration Analysis of Fluid-Conveying Pipes with Periodically Varying Cross-Section

Phononic crystals (PCs) are a novel class of artificial periodic structure, and their band gap (BG) attributes provide a new technical approach for vibration reduction in piping systems. In this paper, the vibration suppression performance and natural properties of fluid-conveying pipes with periodically varying cross-section are investigated. The flexural wave equation of substructure pipes is established based on the classical beam model and traveling wave property. The spectral element method (SEM) is developed for semi-analytical solutions, the accuracy of which is confirmed by comparison with the available literature and the widely used transfer matrix method (TMM). The BG distribution and frequency response of the periodic pipe are attained, and the natural frequencies and mode shapes are also obtained. The effects of some critical parameters are discussed. It is revealed that the BG of the present pipe system is fundamentally induced by the geometrical difference of the substructure cross-section, and it is also related to the substructure length and fluid–structure interaction (FSI). The number of cells does not contribute to the BG region, while it has significant effects on the amplitude attenuation, higher order natural frequencies and mode shapes. The impact of FSI is more evident for the pipes with smaller numbers of cells. Moreover, compared with the conventional TMM, the present SEM is demonstrated more effective for comprehensive analysis of BG characteristics and free vibration of PC dynamical structures.

Optimization design of the octagonal water diffuser with uniform flow orifice plate

Energy storage technology has been widely used in many fields, mainly due to the continuous development of social economy, resulting in increasing power consumption and peak valley load difference. This technology can play the role of adjusting the electric network load. Among them, water storage technology is the most representative. Naturally stratified technology is the most economical and effective method in chilled water storage technique and its core is the design of water diffuser. Octagonal water diffuser with the uniform flow orifice plate is a more effective water distribution mode in the naturally stratified chilled water storage system. In order to get the higher chilled water storage efficiency, the fluid dynamics software was used to make an optimization research on its parameters. Based on the scheme of octagonal diffuser and uniform flow orifice plate, the simulation analysis of the outlet mode of water distribution pipe and the opening parameters of orifice plate were carried out. According to the numerical simulations on the different volume water storage tanks, the comprehensive analysis showed that the diffusion performance of circular opening was better than slot opening, and the thickness of thermocline was thinner when the opening ratio of the orifice plate was 20% than the case of 30% and 45%. In addition, it was pointed out that the porous media model could almost replace the two-dimensional actual opening model under the low opening rate.

Towards the Development of Novel Hybrid Composite Steel Pipes: Electrochemical Evaluation of Fiber-Reinforced Polymer Layered Steel against Corrosion.

Corrosion remains one of the major and most costly challenges faced by the steel industry. Various fiber-reinforced polymer coating systems have been proposed to protect metallic piping distribution networks against corrosion. Despite increasing interest among scientific and industrial communities, there is only limited predictive capability for selecting the optimum composite system for a given corrosive condition. In this study, we present a comprehensive evaluation of the electrochemical behavior of two different fiber-reinforced polymer composite systems against the corrosion of carbon steel pipes under a wide range of acidic and corrosive solutions. The composites were made of glass and Kevlar fibers with an epoxy resin matrix and were subjected to corrosive solutions of 0.5 M NaCl, 0.5 M HCl, and 0.5 M H2SO4. The kinetics of the corrosion reactions were evaluated using potentiodynamic polarization (PDP) tests. In addition, electrochemical impedance spectroscopy (EIS) tests were carried out at open circuit potentials (OCPs). It was demonstrated that the glass fiber-reinforced polymer coating system offered the best protection against corrosion, with a high stability against deterioration when compared with epoxy and Kevlar fiber-reinforced polymer coating systems. Scanning electron microscopy images revealed cracks and deteriorated embedded fibers due to acid attack, sustained/assisted by the diffusion of the corrosion species.

Structure-Property Relationships of Polyamide 12 Grades Exposed to Rapid Crack Extension.

Thermoplastic materials have established a reputation for long-term reliability in low-pressure gas and water distribution pipe systems. However, occasional Slow Crack Growth (SCG) and Rapid Crack Propagation (RCP) failures still occur. SCG may initiate only a small leak, but it has the potential to trigger RCP, which is much rarer but more catastrophic and destructive. RCP can create a long, straight or meandering axial crack path at speeds of up to hundreds of meters per second. It is driven by internal (residual) and external (pressure) loads and resisted by molecular and morphological characteristics of the polymer. The safe installation and operation of a pipe throughout its service lifetime therefore requires knowledge of its resistance to RCP, particularly when using new materials. In this context, the RCP resistance of five different polyamide (PA) 12 grades was investigated using the ISO 13477 Small-Scale Steady State (S4) test. Since these grades differed not only in molecular weight but also in their use of additives (impact modifiers and pigments), structure-property relationships could be deduced from S4 test results. A new method is proposed for correlating these results more efficiently to evaluate each grade using the crack arrest lengths from individual S4 test specimens.

Performance evaluation of sub ground passive cooling system with Ecotech software simulation (Case study: Pasio Christi Church at Cibunut, Kuningan, West Java)

The church in Cibunut, Kuningan, West Java has implemented a sub ground passive cooling system in its renovated building in 2018. This sub ground passive cooling system has not been widely applied in tropical regions, however the church is trying to implement it. This system is supported by making air wells and flowing cold air through distribution pipes into the room. Because not many people have implemented this system, performance evaluation through an ecotect software simulation is used to determine the success of the system in cooling the room. The research was carried out with the following steps: (i) Data collection in the form of CAD drawings of Cibunut Church building, (ii) Simulation using ecotect software, and (iii) Analysis of simulation results with thermal comfort standards in the tropics. The results of this study are conclusions from the results of simulations and analyzes, as an illustration in applying of the sub ground passive cooling system. This research helps illustrate the difference between buildings that have not applied sub ground passive cooling and buildings that have applied sub ground passive cooling.

Planning of clean water distribution network Kamosope Village, Pasir Putih District, Muna Regency

The availability of clean water is essential for human life because clean water is the primary human need. It is imperative to plan a clean water supply system that is appropriately managed. Kamosope Village does not yet have a reasonable and adequate clean water network system, so it is necessary to plan a sound clean water supply network system to serve the community. The source of water to be used is river water. The designed clean water network system collects water from the river then the water is distributed to the population through a gravity system. The clean water network system is planned to meet the needs of clean water until 2029. The need for clean water is calculated based on the projected population using the Least Square method. From the calculation results, the need for clean water in Kamosope Village in 2029, with 723 people, reaches 1.753 liters/second. Kamosope river discharge based on field measurements using the buoy method is 0.535 m³/second or 107 liters/second. Distribution pipe diameters are the inch, 1 inch, 1½ inch, and 2 inches. EPANET 2.0 software is used to design the clean water network system.

„Fliegendes” Andrehen mit einer Gripper‐TBM in Flach‐ und Steilstrecke

AbstractContractor G. Hinteregger &amp; Söhne Baugesellschaft mbH submitted an alternative proposal for the ”Rodundwerk I, new headrace and distribution pipe system“ project commissioned by Illwerke vkw AG which uses a new launch structure for an open gripper TBM. An Austrian utility model has been registered for this new development. This paper describes the process.