Pipeline Size Research Articles

Fault Diagnosis Based on Belief Rule Base With Considering Attribute Correlation

With the growing demand for high safety in industrial system, fault diagnosis has attracted more and more attention. Currently, belief rule base (BRB) has shown an excellent performance in modeling complex system, where the expert knowledge is used effectively. Existing BRB models are assumed that the inputs of the attributes are independent and the attribute correlation is not taken into account. However, in some engineering system, there is an obvious correlation among these attributes. The correlated attributes may produce redundant information which limits the abilities of attributes to express the accurate information of system. In this paper, a new BRB model with considering attribute correlation (BRB-c) is proposed. Moreover, a decoupling matrix is introduced to eliminate the redundant information from the attributes. The initial parameters of the decoupling matrix are given according to the expert knowledge. And then, when the inputs of the attributes are available, the parameters in the decoupling matrix are trained by an optimization model. The projection covariance matrix adaption evolution strategy is chosen as an optimization algorithm. A practical case study about fault diagnosis of oil pipeline is conducted and the results show that the BRB-c model can diagnose the leak size and leak time of oil pipeline accurately, which can demonstrate that the proposed model can be widely applied in engineering for fault diagnosis.

On slug frequency in concurrent high viscosity liquid and gas flow

Slug frequency is an important input parameter in most mechanistic and semi-mechanistic models used for estimating slug flow characteristics such as pressure gradient, slug length and slug holdup. It is also essential in the design and sizing of transport and/or production pipelines, process flow control, design and operation of process equipment, etc. This study experimentally investigates slug frequency in two horizontal pipelines with internal diameters (ID) of 0.0254 and 0.0764 m. Test liquids used in the study were mineral oil (with viscosity ranging from 1.0 to 4.0 Poise) and water while compressed air is the gas phase. Effects of liquid viscosity, gas superficial velocity, liquid superficial velocity, pipe internal diameter, pipe length and pressure gradient are discussed. Results indicate that slug frequency increased with increase in oil viscosity; decreased with increase in pipe diameter; and reduces along the length of the pipe. For gas Reynolds number, ReSG≤2500, slug frequency increased with increase in gas superficial velocity, when ReSG>2500, slug frequency decreased with increase in gas superficial velocity. A new slug frequency correlation that accounts for liquid viscosity and gas superficial velocity, hitherto not included in other correlations was proposed. A comparative analysis of the proposed models and existing slug frequency correlation on a high viscosity databank showed that the proposed correlation gave the best prediction with an average absolute percentage error (AAPE) of 19.91%.

Simulation analysis of solution transportation absorption chiller with a capacity from 90 kW to 3517 kW

The utilization of waste heat instead of fuel combustion is effective in reducing primary energy consumption to mitigate global warming problems. As waste heat sources are not necessarily located close to areas of heat demand, one of the difficulties is that waste heat must be transferred from the heat source side to the heat demand side, which may require the transportation of heat over long distances. From this point of view, we proposed and examined a new idea of heat transportation using ammonia-water as the working fluid in the system named the Solution Transportation Absorption chiller (STA). Our previous studies of the STA were mainly based on the experimental investigation with the STA facility where the cooling power was 25 RT (90 kW). Thus, the Coefficient of Performance (COP) of STA was found to have almost the same value of 0.65 with conventional absorption chillers without depending on the transportation distances. The simulation using AspenHYSYS also examined the same experimental condition. The experimental data showed good agreement with the simulation calculation. In this study, we examined the large-scale cooling power of the STA on the simulation. The intention of this study was to analyze sensitivity with large cooling capacities, the examined cooling powers were from 90 kW (25 RT) to 3517 kW (1000 RT). All cooling power achieved around COP 0.64 including pump power consumption. In addition, we performed a dynamic simulation. The results showed that pipeline size did not affect the cooling capacities and mass flow rates. Furthermore, the stability time of the cooling capacities and mass flow rates were almost the same regardless of the pipeline size and cooling capacity. In other words, the STA may achieve the same COP despite having various complex conditions compared with the conventional absorption chiller.

Analysis of design characteristics of a V-type support using an advanced engineering environment

Modern mining support, for the entire period of their use, is the important part of the mining complex, which includes all the devices in the excavation during his normal use. Therefore, during the design of the support, it is an important task to choose the shape and to select the dimensions of a support as well as its strength characteristics. According to the rules, the design process of a support must take into account, inter alia, the type and the dimensions of the expected means of transport, the number and size of pipelines, and the type of additional equipment used excavation area. The support design must ensure the functionality of the excavation process and job security, while maintaining the economic viability of the entire project. Among others it should ensure the selection of a support for specific natural conditions. It is also important to take into consideration the economic characteristics of the project. The article presents an algorithm of integrative approach and its formalized description in the form of integration the areas of different construction characteristics optimization of a V-type mining support. The paper includes the example of its application for developing the construction of this support. In the paper is also described the results of the characteristics analysis and changings that were introduced afterwards. The support models are prepared in the computer environment of the CAD class (Siemens NX PLM). Also the analyses were conducted in this design, graphical environment.

Considerations in the Development of Flexible CCS Networks

This paper discusses considerations for the design of flexibly operated Carbon Capture and Storage (CCS) pipeline networks and is based on the findings of the Flexible CCS Network Development project (FleCCSnet), funded as part of the UK CCS Research Centre. The project considered the impact of flexibility across the whole CCS chain, as well as studying the interfaces between each element of the system; e.g. at the entry to the pipeline system from the capture plant and at the exit from the pipeline to the storage site. The factors identified are intended to allow CCS network designers to determine the degree of flexibility in the system; allowing them to react effectively to short, medium and long term variations in the flow of CO2 from capture plants and the constraints imposed on the system by CO2 injection and storage.The work of the project is reviewed in this paper which explores the flexibility of power plants operating with post combustion capture systems; quantifies the available time to store (line pack) CO2 in the pipeline as a function of pipeline size, the inlet mass flow rate and operating pressure; and explores the influence that uncertainty in injection and storage parameters have on the design of the pipeline. In addition, parameters influencing short and longer term network designs are discussed in terms of varying flow rates. Two practitioner workshops [1,2] contributed to the direction of the project. The first workshop identified and confirmed key questions to be considered in order to understand the most likely impacts of variability in both the CO2 sources and CO2 sinks on CO2 transport system design and operation. The second workshop focused on transient issues in the pipeline and storage site.Although the case studies in the work are UK based, this work is applicable to other situations where large and small sources of CO2 are expected to be feeding into a CCS transportation system. The work is expected to inform a broad range of stakeholders and allow network designers to anticipate potential problems associated with the operation of a CCS network. For an effective design of CCS infrastructure, all of the factors that will have a substantial impact on CO2 flow will have to be analysed at an early stage to prevent possible bottle necks in the whole chain.

Experimental evaluation of a vibration-based leak detection technique for water pipelines

Conventional water pipeline leak detection surveys employ labour-intensive acoustic techniques, which are usually expensive and not amenable for continuous monitoring of distribution systems. Many previous studies attempted to address these limitations by proposing and evaluating a myriad of continuous, long-term monitoring techniques. However, these techniques have difficulty to identify leaks in the presence of pipeline system complexities (e.g. T-joints), offered limited compatibility with popular pipe materials (e.g. PVC), and were in some cases intrusive in nature. Recently, a non-intrusive pipeline surface vibration-based leak detection technique has been proposed to address some of the limitations of the previous studies. This new technique involves continuous monitoring of the change in the cross-spectral density of surface vibration measured at discrete locations along the pipeline. Previously, the capabilities of this technique have been demonstrated through an experimental campaign carried out on a simple pipeline set-up. This paper presents a follow-up evaluation of the new technique in a real-size experimental looped pipeline system located in a laboratory with complexities, such as junctions, bends and varying pipeline sizes. The results revealed the potential feasibility of the proposed technique to detect and assess the onset of single or multiple leaks in a complex system.

DALiuGE: A graph execution framework for harnessing the astronomical data deluge

Abstract The Data Activated Liu 1 Graph Engine – DALiuGE 2 – is an execution framework for processing large astronomical datasets at a scale required by the Square Kilometre Array Phase 1 (SKA1). It includes an interface for expressing complex data reduction pipelines consisting of both datasets and algorithmic components and an implementation run-time to execute such pipelines on distributed resources. By mapping the logical view of a pipeline to its physical realisation, DALiuGE separates the concerns of multiple stakeholders, allowing them to collectively optimise large-scale data processing solutions in a coherent manner. The execution in DALiuGE is data-activated, where each individual data item autonomously triggers the processing on itself. Such decentralisation also makes the execution framework very scalable and flexible, supporting pipeline sizes ranging from less than ten tasks running on a laptop to tens of millions of concurrent tasks on the second fastest supercomputer in the world. DALiuGE has been used in production for reducing interferometry datasets from the Karl E. Jansky Very Large Array and the Mingantu Ultrawide Spectral Radioheliograph; and is being developed as the execution framework prototype for the Science Data Processor (SDP) consortium of the Square Kilometre Array (SKA) telescope. This paper presents a technical overview of DALiuGE and discusses case studies from the CHILES and MUSER projects that use DALiuGE to execute production pipelines. In a companion paper, we provide in-depth analysis of DALiuGE’s scalability to very large numbers of tasks on two supercomputing facilities.

Disruption of drug-resistant biofilms using de novo designed short α-helical antimicrobial peptides with idealized facial amphiphilicity.

Antimicrobial peptides (AMPs) are increasingly explored as therapeutics for drug-resistant and biofilm-related infections to help expand the size and quality of the current antibiotic pipeline in the face of mounting antimicrobial resistance. Here, synthetic peptides rationally designed based upon principles governing the folding of natural α-helical AMPs, comprising the backbone sequence (X1Y1Y2X2)n, and which assemble into α-helical structures with idealized facial amphiphilicity, is presented. These multifunctional peptide amphiphiles demonstrate high bacterial selectivity, promote the disruption of pre-formed drug-resistant biofilms, and effectively neutralize endotoxins at low micromolar concentrations. Overall, the design strategies presented here could provide a useful tool for developing therapeutic peptides with broad-ranging clinical applications from the treatment and prevention of drug-resistant biofilms to the neutralization of bacterial endotoxins.

Development of RFECT system for in-line inspection robot considering extendibility of receiving sensors based on parallel lock-in amplifier

This paper proposes a new and effective approach to design a remote-field eddy current testing (RFECT) system equipped with a large number of sensors in order to provide full circumferential coverage of pipelines larger than 6 inches. By developing a parallel digital lock-in amplifier (LIA), the extendibility of receiving sensors can be achieved, and therefore, the modification of RFECT systems, which should be accompanied by sufficiently securing the receiving sensors whose number increases with the pipeline size, can be minimized. Using the design method for an RFECT system based on a parallel digital LIA, a new non-destructive testing (NDT) platform that can be applied to RFECT systems of various sizes without modifying the system architecture is developed. It is then applied to an RFECT system that can be mated with an in-line inspection (ILI) robot and has 36 receiving sensors to inspect unpiggable gas pipelines. The performance of the RFECT system is verified with respect to the sensitivity and the accuracy of defect characterization though the pull-rig test having a number of artificial defects.

An Investigation of the Gathering System Options for a Hypothetical Field with Uniformly Distributed Production Wells

The gathering systems in the production wells are very crucial in the transportation of produced liquids from production wells to collection points such as the processing plant or central processing facilities. Liquid transmission pipelines are a part of the energy industry which involves the transportation of natural crude oil through pipelines. In this research the pipeline costs, material costs are proportional to pipeline diameter, whilst construction and design costs are approximately constant. The research shows that the bigger the length of the flow line, the bigger the total pressure drop, per unit length of the flow line for a given size and the type of pipe, the total pressure drop increases with length, whilst the pressure increases from 100 kpa to 250 kpa, and the length of the flow lines increases from 5.4 km to 12.5 km. The inlet pressure of 600 psig was used, as maximum inlet pressure with a design pressure of 1215 psig, with the assumption that protection against closed in tubing head pressure (CITHP) was protected. The investigation shows that a single flow line or trunk lines are not economical in transporting the fluids from the production wells, due to high -pressure drop in the flowline segments and it can affect pipeline diameters since pressure drop can lead to excess inlet pressure to push the liquid through the flow line and the operating costs can be excessive and result in insufficient pressure to pump or transport the fluids to the central processing facility. The modeling of the pressure drop in the flowline at different rates and for different sizes of nominal pipeline in the gathering systems was achieved.

Conceptual design of multi-source CCS pipeline transportation network for Polish energy sector

The aim of this study was to identify an optimal CCS transport infrastructure for Polish energy sector in regards of selected European Commission Energy Roadmap 2050 scenario. The work covers identification of the offshore storage site location, CO 2 pipeline network design and sizing for deployment at a national scale along with CAPEX analysis. It was conducted for the worst-case scenario, wherein the power plants operate under full-load conditions. The input data for the evaluation of CO 2 flow rates (flue gas composition) were taken from the selected cogeneration plant with the maximum electric capacity of 620 MW and the results were extrapolated from these data given the power outputs of the remaining units. A graph search algorithm was employed to estimate pipeline infrastructure costs to transport 95 MT of CO 2 annually, which amount to about 612.6 M€. Additional pipeline infrastructure costs will have to be incurred after 9 years of operation of the system due to limited storage site capacity. The results show that CAPEX estimates for CO 2 pipeline infrastructure cannot be relied on natural gas infrastructure data, since both systems exhibit differences in pipe wall thickness that affects material cost.

Development of In-Pipe Robot D300: Cornering Mechanism

Utilization of robots for in-pipe maintenance considered as one of the most effective ways to improve the pipeline operation. The specific condition and structure of a pipeline system is a challenge for the robots to perform its task. This research aims to assess the characteristic and performance of the in-pipe robot in a 90° pipe elbow. Hence, a prototype of in-pipe robot for 300 mm UPVC pipe diameter (IPR-D300) has been built. The conception of the robot is based on wall-pressed caterpillar type which is suitable for not only horizontal pipeline position, but also vertical and elbows pipeline. This robot is equipped with ultrasonic sensors, high performance microcontroller board and powerful geared motor for travelling in the corner of pipeline. The developed IPR-D300 consist of three independent driving modules that are able to alter the speed according to the pipeline characteristic. The hardware and software of the IPR-D300 performance have been tested and successfully perform the cornering task smoothly. The developed IPR-D300 potentially can be applied for in-pipe cleaning operation especially on centralised sewerage system. As standard pipeline size for sewerage system housing in Malaysia is 200 mm, smaller and robust in-pipe robot will be the future target.

On developing improved modelling and scale-up procedures for pneumatic conveying of fine powders

Pneumatic transport of fine powders in fluidized dense-phase mode is becoming increasingly popular in various industries, such as power, chemical, cement, refinery, alumina, pharmaceutical, limestone, to list a few, because of the reasons of reduced gas flow rate and power consumption, decreased conveying velocities, improved product quality control, reduced pipeline sizing and wear rate, increased workplace safety etc. For the reliable design of a pneumatic conveying system, it is important to accurately predict the total pipeline pressure drop. However, accurate prediction of pressure drop from an improved understanding of the fundamental transport mechanism of fluidized dense-phase flow condition has only made limited progress till now because of the highly concentrated and turbulent nature of the gas-solids mixture. Power plant fly ash (median particle diameter: 30μm; particle density: 2300kg/m3; loose-poured bulk density: 700kg/m3) was conveyed through different pipelines (69mm I.D.×168m long; 105mm I.D.×168m long; 69mm I.D.×554m long). 8 different fly ash samples were tested in a fluidizing column for their deaeration characteristics and fluidized bulk densities were determined. Governing equations of flow for the dense-phase pneumatic conveying system of fine powders were solved using Runge-Kutta-Fehlberg (RKF45) method for different fluidized bulk densities of fly ash and air flow rates. The results have shown that the particle and actual gas velocities and the ratio of the two velocities increase in the direction of flow, while a reverse trend was apparent for the solids volumetric concentration. The results were compared against the predictions obtained using existing empirical relations for particle velocity. To develop an improved model for solids friction factor, an existing reliable pure dilute-phase model has been modified for dense-phase flow condition by incorporating sub-models for particle to actual gas velocity and impact and solids friction factor. The developed solids friction factor model was validated by using it to predict the total pipeline pressure drops for larger and longer pipelines and by comparing the experimental and predicted pneumatic conveying characteristics. The results have shown improved reliable predictions and that the model is capable of addressing the gradual transition of flow mechanism from dense- to dilute-phase. The accuracy of prediction is similar (in fact better in certain scale-up cases) when compared to a recently developed two-layer based model (developed by some of the authors). The results demonstrate the importance of incorporating particle and actual gas velocity terms in the model of solids friction factor instead of the prevailing techniques that overly depend on using superficial gas velocities.

Material stock disparity and factors affecting stocked material use efficiency of sewer pipelines in Japan

Service is most often measured with a flow and monetary perspective using indicators such as gross domestic product (GDP) or the value added or income of a particular economic sector. However, infrastructures and therefore the associated material stocks also participate to the service delivery. Our study contributes to this emerging research field through a novel method of measuring stocked material use efficiency (SMUE) of sewerage pipelines in Japan, beyond monetary measures. We estimated the Japanese national and prefectural material stocks (MS) using statistical data and used direct service indicators such as the population with access to sewerage treatment services and the amount of treated wastewater to find the SMUE. Later, decomposition analysis was used to ascertain the main factors influencing SMUE. Results show an MS increase for all prefectures and a doubling of the national MS from 207 million tonnes (Mt) 520 Mt between 1984 and 2012. Material stocks are found mainly associated with population size, the highest populated prefectures Tokyo and Osaka also accounting for the highest material stocks. Concerning SMUE ranging from 4 to 48m3/ton for a national average of 27m3/ton, its main determinants are population density and pipeline size. This research promotes greater understanding of our stock use condition and thereby facilitates appropriate stock management.

Investigation of the Effect of Pipeline Size on the Cross Flow Injection Process

Injection pumps constitute an essential component for many industrial applications. The main focus of this study is to predict the effect of the size of the pipeline on the cross flow injection process. A test-rig was designed, built and equipped with three different pipelines, 1½", ¾" and ½" diameters. Comparison was made under constant line pressure of 40-bar and line flow rate of 5 liter/min, with a fixed injection pump rotational speed of 100 rpm. The main parameter tested was the injection dose capacity at different pump displacements. Cross flow mixing process is also theoretically studied using 3D-CFD analysis to show the injection cross flow behavior for the same geometry and parameters used for experimental test. Results show that increasing the size of the pipeline increases injection pump doses ability. This effect is insignificant at lower injection pump displacements, while the effect of the size of the pipeline becomes dominant when increasing the displacement. By changing the size of the pipeline from ½" to 1½" diameter injection pump dose capacity increases by 3.24% at 100% pump displacement. Selecting larger pipe sizes for injection ports is recommended whenever possible.

Investigation of the Effect of Pipeline Size on the Cross Flow Injection Process

Investigation of the Effect of Pipeline Size on the Cross Flow Injection Process

Determination of a particle size distribution criterion for predicting dense phase pneumatic conveying behaviour of granular and powder materials

The purpose of this study was to evaluate the effect of particle size distribution on the modes of flow that particulate materials will support in a pneumatic conveying pipeline. It has long been known that some materials can be conveyed in dense phase flow, i.e. a condition wherein the superficial gas velocity is below the saltation value, whereas some materials will block the pipeline under such conditions. It has also been known for a long time that there are two distinct forms of dense phase flow, generally linked to whether the material is fine (such as cement powder), or coarse (such as pellets), but until now there has been no successful method to assess the conveyability of a material based on size distribution alone. Six materials with different size grades were conveyed in a 25mm bore pipeline, at a range of pressures up to 3bar and gas velocities from zero to 12m/s. The results showed that materials below a certain size would support a fluid-like dense phase mode of flow, whereas to support a low-velocity slug flow the key was to have a very narrow size distribution. Materials that satisfied neither of these criteria would not support flow at gas velocities below the saltation value. Clear trends for how throughput changes in the transition from lean to dense phase, are also demonstrated, which have major implications for pipeline sizing. A quantitative criterion for deciding on the likely conveyability of a material, based on size distribution alone, is proposed.

Empirical analysis of large diameter water main break consequences

The recent ASCE report card gave a "D" grade for the state of drinking water infrastructure in the U.S. and reported that there are about 240,000 water main failures annually. Some of these failures result in significant economic, environmental and societal consequences that are difficult to predict for the purpose of accurate risk assessment and subsequent rehabilitation planning. This study analyzed the overall consequences of 20 large diameter water main failures in the U.S., majority of which have occurred in the last seven years, with an objective of identifying factors that aggravate the consequences to be able to reasonably predict them for rehabilitation decision making. It has been found that the overall cost of the failure consequences dependedon several factors that include but not limited to pipeline size, relative elevation and the type of land use, population density, utility response and repair time, and operating pressure.Direct repair of the failed pipeline, followed by property damage and then travel delays, accounted for 35%, 22% and 21% of the overall failure cost on average, respectively. It has also been found that the direct costs which the water utility pays for accounted for only about 41% while the indirect costs which are usually borne by the society accounted for the remaining 59%. While consideration of the overall failure costs as part of rehabilitation planning may increase the investment needs of water utilities, it remains to be investigated as to how much more investment will be required, who would pay for it and how willing are the water utilities in adopting the overall failure cost approach.

Modeling solids friction factor for fluidized dense-phase pneumatic transport of powders using two layer flow theory

Fluidized dense-phase pneumatic conveying of powders is becoming increasingly popular in various industries, such as power, chemical, cement, refinery, alumina, pharmaceutical, limestone, to list a few, due to the reasons of reduced gas flows and power consumption, improved product quality control, reduced pipeline sizing and wear rate, increased workplace safety etc. An accurate estimation of total pipeline pressure drop is of paramount importance for the reliable design of a pneumatic conveying system. However, because of the highly concentrated and turbulent nature of the gas–solids mixture, fundamentally understanding the flow mechanism and accurately predicting the pressure drop as an important design parameter has only made limited progress so far. This paper results from an ongoing investigation into developing a validated modeling procedure for solids friction factor for the accurate prediction of pressure drop and optimal operating conditions for fluidized dense-phase pneumatic conveying systems. Under the present study, a two-layer based model has been developed by separately considering the solids friction contributions of the non-suspension (dense) bed of powders flowing along the bottom of pipe and the suspension (dilute-phase flow) of particles occurring on top of the non-suspension layer. Volumetric loading ratio and dimensionless velocity have been used to model the non-suspension dune flow layer. A solids impact and friction term and dimensionless velocity have been employed to model the dilute-phase flow due their established reliability. Models have been developed using the straight-pipe conveying data of two types of fly ash, cement and ESP dust (median particle diameter: 7 to 30μm; particle density: 2300 to 3637kg/m3; loose-poured bulk density: 610–1080kg/m3). The developed models for solids friction were validated for their scale-up accuracy by using them to predict the pressure drops in five larger and longer pipelines (69mm I.D.×168m long; 105mm I.D.×168m long; 69mm I.D.×554m long, 65mm I.D.×254m long and 80/100mm I.D.×407m long pipes) and by comparing the experimental versus predicted pneumatic conveying characteristics. The two-layer model provided improved accuracy compared to existing models indicating that the model is able to adequately address the dense- to dilute-phase transition criteria.

Hardware Development of Electrical Capacitance Tomography (ECT) System with Capacitance Sensor for Liquid Measurements

Electrical capacitance tomography system is useful for obtaining information about the spatial distribution of a mixture of dielectric materials inside a vessel. This research aims to obtain real-time monitoring on the composition for liquid mixture in conveying pipeline. ECT is a non-invasive, non-intrusive and non-destructive technique that can measure the flow level inside a pipeline. In order to increase the image resolution and accuracy of current tomography research, a study on 16 electrodes sensor ECT system has been developed. The developed system has the flexibility to be assembled and moved from a pipeline to another. The intelligent on-board flexibility and mobility sensor technique is a new technique for ECT system. The system can be assembled in different diameter sizes of pipeline, and numbers of electrodes sensor can be reduced accordingly depending on the pipeline sizes without the need to redesign the electrodes sensor. The new design is equipped with high speed data processing rate data acquisition system and high speed data reconstruction. A microcontroller that support full-speed USB data transfer rate has been designed as the centralization control unit. In order to improve data result, iterative algorithm has been implemented in this system in order to obtain a precise image of the flow in the pipeline. As a result, the ECT system is able to reconstruct various multiphase flow images.