Position Of Pipe Research Articles

Flow field and noise characteristics of manifold in natural gas transportation station

Manifolds play a role of pressure balance, buffering and rectification for different branch pipelines, the flow noise of manifolds has been a serious problem all this time in natural gas transmission station. By changing the number of outlet pipes of manifolds and the different positions of intake pipes, the distribution of the Sound Pressure Level (SPL) of the manifold flow noise is analyzed based on the Ffowcs Williams-Hawkings (FW-H) acoustic analogy theory and Large Eddy Simulations (LESs). The three-dimensional simulation analysis of the flow field shows that pressure pulsation is the mainly source of manifold noise, as the number of outlet pipe increases, the SPLs of fluid dynamic noise at the end of inlet pipes are significantly reduced by about 10 dB on average, when the inlet and outlet piping are oppositely connected, the SPL is 2 dB~3 dB lower than that in staggered connections. An expansion-chamber muffler is designed with the analysis of its noise reduction effect, the results show that after the muffler is installed, the noise reduction in the low-frequency ranges reaches up to 37.5 dB, which controls the maximum noise to around 82 dB.

Are combi parks just as useful as regular parks for fatteners for part-time group housing of rabbit does?

<p>Group housing of lactating rabbit does is desirable from a welfare standpoint, but agonistic behaviour can cause severe skin injuries, which are undesired for animal welfare. Park layout, creating hiding places and escape possibilities, may help redirect attention away from fighting, which could in turn help prevent skin damage. An experiment was performed to test whether more damaging behaviour would occur in a combi park (with nest box panels) after mixing, compared to a regular park for fatteners, as nest box panels would obstruct does when escaping aggressive interactions. In addition, the position of the PVC pipe underneath the platform differed between parks (longitudinal or transversal), resulting in different escape routes. Twenty-two parks were used, in which 5 does per park were grouped at 23 d of lactation until weaning at 36 d of lactation. Skin injuries were scored at 4 d after grouping and on the day before weaning. The presence of nest box panels in a combi park and the position of the PVC pipe underneath the platform did not affect the level of skin damage. Moderate to severe injuries were observed, mostly at the hind quarters, ears and head. Five to 6% of the does were severely injured (wounds). There was a positive relationship between the average skin injury per park at 4 d after grouping and at weaning. On average, average injury score per park increased from grouping to weaning, but there are differences between individual parks. From this experiment it can be concluded that group housing of lactating rabbit does involves animals getting injured. In fact, 5 to 6% of the does were severely injured (wounds). Social dynamics of group housed does are insufficiently understood and might be important to reduce damaging behaviour in group housing.</p>

Microstructure and micropore formation in a centrifugally-cast duplex stainless steel via X-ray microtomography

Cast duplex stainless steels (CDSS) is being extensively used in many industries. The morphology and distribution of ferrite phase present, as well as the micropores defect, significantly influences the hot cracking susceptibility and corrosion resistance of CDSS. In this work, the microstructure and the micropores of the inner wall and outer wall position of a primary coolant pipe used in the pressurized water reactor (PWR) were characterized and compared using a lab scale X-ray microtomography approach. During centrifugal casting process, the local ferrite grains tend to grow in the same direction. Although the ferrite phases seem separated from each other in a two-dimensional (2D) image, most of them are connected in a three-dimensional (3D) view. Solution treatment can result in homogeneous distribution in both fraction and morphology of ferrite phase. Micropores always form along the ferrite/austenite interface and the inner wall position is more prone to porosity.

Analyzing Influence of Ignition Gas Flow Pipe of Igniter on Working Process

Based on gas dynamics and computational fluid dynamics, the numerical simulation of the steady-state flow field of igniter working in the two conditions was conducted with FLUENT. The numerical simulation results were validated by experiments. Influences of ignition gas flow pipe on the igniter's working performance were analyzed on the basis of test validation. The analysis results show that the combustion chamber pressure has atmospheric pressure and that the igniter works with ignition gas flow pipe. The velocity of throat is lower than the speed of sound and the sonic position moves to the position of ignition gas flow pipe; the velocity, pressure and temperature of throat increase; but the flux, pressure and temperature of outlet decrease. Under the different conditions of combustion chamber pressure, the outlet velocity, pressure, temperature and flux have a stable section; but the flux decreases.

Development of media learning practice welding pipe position vertical axis (2G) with Gas Metal Arc Welding process (GMAW) in senior high school

This research develops old media by creating new media. The reason, because of the improper application of the pipeline welding procedure that caused misconceptions of learners, his assumption of piping can be rotated and shifted. With the new media will minimize the problem. The practical media device helps weld the vertical axis position pipe (2G) with GMAW process, the weld pipe dimension is at least two to four inches. Standard procedure, fixed pipe, incendiary rotator in the same direction or counter clockwise. Mechanization and automation of pipe welding produces high productivity, because the weld bead is better. The results of this study indicate the effectiveness of pipe welding systems and practices with indicators of students able to master the welding of pipes with and without the media mentioned above.

Precision measurement of the structure of the CMS inner tracking system using nuclear interactions

The structure of the CMS inner tracking system has been studied using nuclear interactions of hadrons striking its material. Data from proton-proton collisions at a center-of-mass energy of 13 TeV recorded in 2015 at the LHC are used to reconstruct millions of secondary vertices from these nuclear interactions. Precise positions of the beam pipe and the inner tracking system elements, such as the pixel detector support tube, and barrel pixel detector inner shield and support rails, are determined using these vertices. These measurements are important for detector simulations, detector upgrades, and to identify any changes in the positions of inactive elements.

Detection and Positioning of Pipes and Columns with Autonomous Multicopter Drones

A multimodal sensory array to accurately position aerial multicopter drones with respect to pipes has been studied, and a solution exploiting both LiDAR and vision sensors has been proposed. Several challenges, including detection of pipes and other cylindrical elements in sensor space and validation of the elements detected, have been studied. A probabilistic parametric method has been applied to segment and position cylinders with LIDAR, while several vision-based techniques have been tested to find the contours of the pipe, combined with conic estimation cylinder pose recovery. Multiple solutions have been studied and analyzed, evaluating their results. This allowed proposing an approach that combines both LiDAR and vision to produce robust and accurate pipe detection. This combined solution is validated with real experimental data.

Localized pitting corrosion of API 5L grade A pipe used in industrial fire water piping applications

In this present paper, failure analysis is conducted for a pipe used in fire water applications. In petroleum industries many failures were observed in API 5 L grade steel pipes. The past inspection history records were observed, which reveals that failed pipeline is poorly maintained since construction. Visual inspection, macroscopic and microscopic examinations were conducted for the failed pipe. The microscopic analysis reveals that the pitting corrosion is a root cause of failure which perforates the wall thickness at 6′o′ clock pipe position. The mechanism of pitting corrosion is correlated with ferrite matrix dissolution. The Cu, Co & Zn ions were detected in scale deposits reveals that the fire water is severely contaminated by various makeup water sources which results in under deposit corrosion. The various sources of foreign elements are discussed in detail. The copper deposits identified at suspected location attributed to galvanic corrosion. Moreover, the severity of pitting is aggravated by grain boundary attack which acts as an anode during corrosion process. Based on various experimental evidences, the conclusions were drawn and further recommendations are discussed to mitigate the corrosion failure.

Evaluation of a Compact Coaxial Underground Coal Gasification System Inside an Artificial Coal Seam

The Underground Coal Gasification (UCG) system is a clean technology for obtaining energy from coal. The coaxial UCG system is supposed to be compact and flexible in order to adapt to complicated geological conditions caused by the existence of faults and folds in the ground. In this study, the application of a coaxial UCG system with a horizontal well is discussed, by means of an ex situ model UCG experiment in a large-scale simulated coal seam with dimensions of 550 × 600 × 2740 mm. A horizontal well with a 45-mm diameter and a 2600-mm length was used as an injection/production well. During the experiment, changes in temperature field and product gas compositions were observed when changing the outlet position of the injection pipe. It was found that the UCG reactor is unstable and expands continuously due to fracturing activity caused by coal crack initiation and extension under the influence of thermal stress. Therefore, acoustic emission (AE) is considered an effective tool to monitor fracturing activities and visualize the gasification zone of coal. The results gathered from monitoring of AEs agree with the measured data of temperatures; the source location of AE was detected around the region where temperature increased. The average calorific value of the produced gas was 6.85 MJ/Nm3, and the gasification efficiency, defined as the conversion efficiency of the gasified coal to syngas, was 65.43%, in the whole experimental process. The study results suggest that the recovered coal energy from a coaxial UCG system is comparable to that of a conventional UCG system. Therefore, a coaxial UCG system may be a feasible option to utilize abandoned underground coal resources without mining.

Study on the influence of water flow on temperature around freeze pipes and its distribution optimization during artificial ground freezing

Artificial ground freezing is usually used to improve ground and provide temporary support. However, the freezing process is dramatically influenced by water flow. Evidently, water flow with high velocity brings large heat energy that prevents the freezing of porous media around freeze pipes. In this paper, for safety and energy-saving, the influence of water flow on freezing process is simulated by a developed coupled hydro-thermal model considering water/ice phase transition and the positions of freeze pipes around circular tunnel are optimized through combining this model with Nelder–Mead simplex method based on COMSOL multiphysics platform. According to the evolution law of freezing band under well-distribution of freeze pipes, three kinds of potential frequently-used probability distribution functions are adopted to reduce control parameters and improve the efficiency of optimization program including normal distribution, Poisson distribution and chi-square distribution. The results show that the proposed combining simulation method is suitable for optimization of freeze pipes arrangement. The freezing time is significantly reduced no matter which one of the above distribution functions is employed through careful design.

Recirculation zone characteristics research on a sudden expansion swirl burner for DPF regeneration

Based on the autonomously designed sudden expansion swirl burner and combined with the characteristics of diesel particulate filter (DPF) regeneration, fitting geometric parameters and values were determined with the orthogonal experimental design method. And the effects of main geometric parameters such as the sudden expansion ratio, length‐diameter ratio and position of air supply pipe on main evaluation indexes of the recirculation zone characteristics were studied with CFD. Results showed that with the geometry of sudden expansion ratio 2.0 and length‐diameter ratio 2.1 and air supply pipe located in the middle of the combustion chamber, the length of the recirculation zone in the center could be increased greatly; in order to increase the reattachment length, the sudden expansion ratio should be 1.5–2.0 and the length–diameter ratio should be larger and the air supply pipe should be closer to the fuel spray nozzle; and the swirl intensity was mainly depended on the length–diameter ratio, which could be effectively enhanced when the length–diameter ratio ranged from 2.1 to 2.4. It provides beneficial references for the research of complex flow field in sudden expansion swirl burner and porous medium. © 2018 American Institute of Chemical Engineers Environ Prog, 37: 1901–1907, 2018

Neural-Fuzzy model Based Steel Pipeline Multiple Cracks Classification

While pipes are cheaper than other means of transportation, this cost saving comes with a major price: pipes are subject to cracks, corrosion etc., which in turn can cause leakage and environmental damage. In this paper, Neural-Fuzzy model for multiple cracks classification based on Lamb Guide Wave. Simulation results for 42 sample were collected using ANSYS software. The current research object to carry on the numerical simulation and experimental study, aiming at finding an effective way to detection and the localization of cracks and holes defects in the main body of pipeline. Considering the damage form of multiple cracks and holes which may exist in pipeline, to determine the respective position in the steel pipe. In addition, the technique used in this research a guided lamb wave based structural health monitoring method whereas piezoelectric transducers will use as exciting and receiving sensors by Pitch-Catch method. Implementation of simple learning mechanism has been developed specially for the ANN for fuzzy the system represented.

Numerical analysis on dynamic stress and vibration for tubular joints of welded steel pipes under axial loads

Reported researches rarely focus on dynamic stress concentration factors (SCF) of tubular joints between the chord and brace, where the chord is a square pipe, and the brace is a circular pipe. Tubular joints between a square pipe and circular pipe are widely applied in spatial structures as a support structure. Therefore, tubular joints of welded steel pipes under axial loads were studied numerically for determination of dynamic stress concentration factors (SCF). Finite element models were setup for a total of 165 tubular joints with various configurations, obtaining dynamic stress distributions of each model along the joint. Dynamic stress concentration factors on the brace and the chord were extracted respectively. Relations between sizes of dynamic stress concentration factors between the joint and structural parameters were discussed. The computational model was finally validated by the experimental test. The experimental curve was basically consistent with the finite element at the elastic stage of loading, indicating that the computational model at the elastic stage was very accurate. The paper mainly studied dynamic stress distribution of the tubular joint of welded steel pipes under an excitation load at the elastic stage, so the finite element model could be used to replace experimental test. SCF was 180° symmetric under different parameters. This angle was located at the crown point of tubular joints, while the welded steel pipe structure was a symmetric structure relative to the longitudinal plane. In addition, the chord and brace had SCF peaks at the angles of 90° and 270° because the two points were located at the saddle point of the tubular joints. Under angles of 0° and 180°, the SCF had obvious valley values because the two points were located at crown points of tubular joints. Finally, the vibration performance of the tubular joint was also analyzed. Vibration displacement could be reduced obviously through reinforcement of tubular joints with the collar plates. Axial pre-tensile forces would increase vibration displacement on top and bottom positions of the chord pipe. This paper can provide an important reference for the improvement of the dynamic stress concentration of joints of welded steel pipes.

Effects of evaluated temperature on tribological behaviors of micro-arc oxidated 2219 aluminum alloy and their field application

The effect of evaluated temperatures on tribological properties of micro-arc oxidated (MAO) 2219 aluminum alloy was investigated. Tribotests were carried out under 25, 80, 120, and 160 °C, and the field drilling test was carried out in “Yang D1 Well”. The results reveal that the friction coefficient of MAO sample decreases with the increase of temperature, the wear rate of MAO sample increases with the increase of temperature, and the load bearing capacity of MAO coating reduces when the temperature goes up. However, comparing with the untreated sample, the wear rate of MAO sample is reduced by 60% at 160 °C. The main wear mechanism of MAO sample is slight abrasive wear under high temperature. The outer loose layer of MAO coating is obviously sheared off under low load and high temperature, resulting in the decrease of friction coefficient. The low loading capacity causes the high wear rate of aluminum alloy at elevated temperature. In the field application, the minimum amount of wear loss is 0.06 mm in the B position of the MAO aluminum alloy drilling pipe.

Investigating reduction of uplift forces by longitudinal drains with underlined canals

A provision of drainage systems with underlined canals is investigated aiming to reduce uplift forces and to increase canal stability when groundwater surface is high, without which failure is likely from subsequent heaving and cracking of canal lining. The investigation generates sufficient data for typical 2D canal cross-sections by numerically solving a wide range of configurations using a provision of drain pipes. The generated data comprise the correlation between uplift forces and the various configuration parameters in terms of effects of position of the drain pipes, their size and hydraulic factors, such as the effect of phreatic surface. These data-sets were used to develop both regression model and an Artificial Neural Network model. Results showed that application of drain pipes under the canal bed at appropriate positions is effective in reducing groundwater depth and thereby reducing uplift pressures.

Comprehensive numerical simulation analysis of flow and mass transfer by tuning inlet conditions in solution circulating technique focused to grow quality KDP crystal

The inclusions are easily to be generated because of the nonuniform distribution of supersaturation of crystal surface in KDP crystal growth process, and the inclusions can reduce the growth quality of crystal. So in order to increase the growth rate of crystal and improve the uniformity of surface supersaturation, the numerical simulation of hydrodynamics and mass transfer in the growth of KDP crystal by using solution circulating method have been performed in this paper. The KDP crystal is in eccentric motion in the calculation model, and the effects of inlet velocities, positions of inlet pipe, and incident angles on the crystal growth are discussed. The surface supersaturation and standard deviation of supersaturation are obtained as functions of different inlet velocities, positions of inlet pipe, and incident angles. The value of surface supersaturation is higher and the standard deviation of surface supersaturation is lower when the inlet pipe and crystal are at the same height. Besides, the uniformity of crystal is improved obviously when the axis of inlet pipe is tangent to the rotation track of R-Py tip.

Passive detection of scatterer using autocorrelation of surf noise

When a scatterer is located in a diffuse noise field, time domain Green's function between two different receivers can be extracted from cross-correlation of ambient noise which is recorded by the two receivers so that target detection can be implemented. However, the method based on cross-correlation strongly depends on timing synchronization of each receiver, otherwise there will be a time drift in the cross-correlation result, which can bring error in the positioning detection. Besides, two receivers that are far from each other must communicate with each other to implement cross-correlation in real-time data processing, but big data transmission is difficult in the ocean. Compared with cross-correlation, autocorrelation means that each receiver works independently and only the final autocorrelation result is to be transmitted. Actually, the scattered wave of target is always so weak that it is submerged in the autocorrelation result of the ambient noise. In this paper, we propose a method of processing the autocorrelation of the ambient noise. When the averaging noise autocorrelation of all receivers is subtracted from the autocorrelation result of the noise recorded by each receiver, the signalnoise ratio of the scattered wave will be significantly enhanced. With the help of Kirchhoff migration algorithm, detection of a scatterer can be implemented. We have conducted a scatterer passive detection experiment in Shilaoren beach, Qingdao, and accurately detected the position of a polyviny chloride pipe (about 8 m away from the nearest receiver) using only 12 min surf noise data. The experimental result shows that the processing of autocorrelation could replace cross-correlation in passive target detection when the ambient noise is time steady and the statistical characteristics of the background noise at different receivers are the same. Unlike Green's function extracted from cross-correlation of ambient noise, each receiver can work independently without considering the problems of massive data transmission and timing synchronization, which may be suitable for target detection using multi-receivers and mobile platform.

Analysis of the Suppression Device as Vortex Induced Vibration (VIV) Reducer on Free Span using Finite Element Method

Subsea pipeline is a transportation infrastructure of oil and gas as an alternative for ship tanker. The uneven topography surface of the sea floor resulting the pipe undergoes free span. The free span is a condition endured by the pipe where the pipe position has distance or gap with the seabed supported by two pivot. The free span is at risk of experiencing a vibration caused by the presence of dynamic load that is current and the wave. The vibration that occurs is the impact of the presence of the phenomenon of Vortex Induced Vibration (VIV). The Phenomenon Of VIV occur on a cylindrical component caused by ocean currents, causing the occurrence of vibration by the movement of fluid on the pipe so that it raises the vortex at the rear of the direction of oncoming flow. One way to dampen or reduce the impact of VIV is by adding suppresion device. VIV suppression device is a tool that is installed on the pipeline on offshore piping installationcthat serves to dampen or reduce the impact of VIV. One of the simulations used to know the characteristics of a fluid is to use (CFD) Computational Fluid Dynamic. With the addition of suppression device can add the rest of the operating time on a free span of affected VIV, on the condition of free span critical exposed VIV (Vortex Induced Vibration value) has a life time on plain pipe 44.21 years, on pipe with 53.09 years and Fairing on the pipe with the Helical strike 52.95 year.

Microwave‐based system for non‐destructive monitoring water pipe networks using support vector machine

Water is the most valuable natural resource. To preserve this good, several water monitoring systems for pipe networks have been proposed. However, there is a lack of research on the development of high-frequency electromagnetic sensors for this task. This study proposes a non-destructive technique to locate carrying water polyvinyl chloride pipes using a microstrip patch antenna. An experimental apparatus was mounted and the resonant frequency and Q factor of the antenna were measured for different relative positions between the sensor and the pipe filled with water. To detect the pipe position, experimental data were trained and tested by applying an approach based on support vector machines. The best results were from using a simple linear kernel, which allowed 100% accuracy using a 30% fraction of data used for holdout validation.

Eulerian-Eulerian Simulation of Particle-Liquid Slurry Flow in Horizontal Pipe

In this study, a computational fluid dynamics (CFD) simulation which adopts the inhomogeneous Eulerian-Eulerian two-fluid model in ANSYS CFX-15 was used to examine the influence of particle size (90 μm to 270 μm) and in situ particle volume fraction (10% to 40%) on the radial distribution of particle concentration and velocity and frictional pressure loss. The robustness of various turbulence models such as thek-epsilon(k-ε),k-omega(k-ω), SSG Reynolds stress, shear stress transport, and eddy viscosity transport was tested in predicting experimental data of particle concentration profiles. Thek-epsilon model closely matched the experimental data better than the other turbulence models. Results showed a decrease in frictional pressure loss as particle size increased at constant particle volume fraction. Furthermore, for a constant particle volume fraction, the radial distribution of particle concentration increased with increasing particle size, where high concentration of particles occurred at the bottom of the pipe. Particles of size 90 μm were nearly buoyant especially for high particle volume fraction of 40%. The CFD study shows that knowledge of the variation of these parameters with pipe position is very crucial if the understanding of pipeline wear, particle attrition, or agglomeration is to be advanced.