Home / Advanced Search

  • Title/Keywords

  • Author/Affliations

  • Journal

  • Article Type

  • Start Year

  • End Year

Update SearchingClear
  • Articles
  • Online
Search Results (42)
  • Open Access


    Fiber Grating-Based Strain Sensor Array for Health Monitoring of Pipelines

    Hui Wang1, Songyou Li2, Lei Liang3,*, Gang Xu4,5, Bin Tu6

    Structural Durability & Health Monitoring, Vol.13, No.4, pp. 347-359, 2019, DOI:10.32604/sdhm.2019.05139

    Abstract Pipelines are one of the most important modern energy transportation methods, used especially for the transportation of certain dangerous energy media materials such as crude oil, natural gas, and chemical raw materials. New requirements have been put forward for the health monitoring and early security warning of pipelines because of the large-scale and complicated development trend of the pipe network system. To achieve an accurate assessment of the health conditions of pipeline infrastructure, obtaining as many precise operating parameters as possible, particularly at some critical parts of the pipeline, is necessary. Therefore, a novel type of fiber grating strain sensor… More >

  • Open Access


    Fatigue Investigations on Steel Pipeline Containing 3D Coplanar and Non-Coplanar Cracks

    Zhongmin Xiao1, Wengang Zhang2, Yanmei Zhang1, *, Mu Fan3

    CMC-Computers, Materials & Continua, Vol.62, No.1, pp. 267-280, 2020, DOI:10.32604/cmc.2020.06567

    Abstract Fluctuated loadings from currents, waves and sea ground motions are observed on offshore steel pipelines, and they will result in small cracks to propagate continuously and cause unexpected damage to offshore/geotechnical infrastructures. In spite of the availability of efficient techniques and high-power computers for solving crack problems, investigations on the fatigue life of offshore pipelines with 3D interacting cracks are still rarely found in open literature. In the current study, systematic numerical investigations are performed on fatigue crack growth behaviours of offshore pipelines containing coplanar and non-coplanar cracks. Extended finite element method (XFEM) is adopted to simulate the fatigue crack… More >

  • Open Access


    Pipeline Defect Detection Cloud System Using Role Encryption and Hybrid Information

    Ce Li1,2,*, Xinyu Shang2, Liguo Zhang3,4, Feng Yang1,2, Jing Zheng1,5, Xianlei Xu1

    CMC-Computers, Materials & Continua, Vol.61, No.3, pp. 1245-1260, 2019, DOI:10.32604/cmc.2019.06159

    Abstract Pipeline defect detection systems collect the videos from cameras of pipeline robots, however the systems always analyzed these videos by offline systems or humans to detect the defects of potential security threats. The existing systems tend to reach the limit in terms of data access anywhere, access security and video processing on cloud. There is in need of studying on a pipeline defect detection cloud system for automatic pipeline inspection. In this paper, we deploy the framework of a cloud based pipeline defect detection system, including the user management module, pipeline robot control module, system service module, and defect detection… More >

  • Open Access


    Application of GB/T 19426-2004 “Safety Assessment for In-Service Pressure Vessels Containing Defects” to the Long-Distance Oil Pipeline

    Zihua Zhao1, Yu Zhou, Zheng Zhang, Qunpeng Zhong

    Structural Durability & Health Monitoring, Vol.6, No.2, pp. 101-112, 2010, DOI:10.3970/sdhm.2010.006.101

    Abstract Annex H"Safety assessment method for straight pressure pipeline with local thinning area" of "Safety assessment for in-service pressure vessels containing defects"(GB/T 19426-2004) is briefly introduced. The maximum allowable hanging (unsupported) length of straight pressure pipeline with a local thinning area (LTA) is then determined by using this assessment method. This is the first time that the assessment method has been applied to the long-distance oil pipeline. As a typical case, we have analyzed a length of straight pressure pipeline with LTA and gave the relationship of maximum allowable unsupported length, operating pressure and the depth of LTA. More >

  • Open Access


    Numerical Study of Trapped Solid Particles Displacement From the Elbow of an Inclined Oil Pipeline

    Dingqian Ding1,2, Yongtu Liang1,*, Yansong Li1,3, Jianfei Sun1, Dong Han1, Jing Liu4

    CMES-Computer Modeling in Engineering & Sciences, Vol.121, No.1, pp. 273-290, 2019, DOI:10.32604/cmes.2019.07228

    Abstract The solid particle impurities generated by pipe wall corrosion might deposit at the elbow of hilly pipelines during the production shutdown of oil pipelines. These solid particle impurities will seriously affect the safety of the pipeline operation and the quality of the petroleum products. Thus, it is necessary to study the methods of removing these trapped particles from pipelines. At present, the most common way to remove these solid particle impurities is pigging oil pipelines periodically by utilizing the mechanical pigging method, while the frequent pigging operation will increase the cost and risk of pipeline operation. It is very convenient… More >

  • Open Access


    Leak Detection of Gas Pipelines Based on Characteristics of Acoustic Leakage and Interfering Signals

    Lingya Meng1, *, Cuiwei Liu2, Liping Fang2, Yuxing Li2, Juntao Fu3

    Sound & Vibration, Vol.53, No.4, pp. 111-128, 2019, DOI:10.32604/sv.2019.03835

    Abstract When acoustic method is used in leak detection for natural gas pipelines, the external interferences including operation of compressor and valve, pipeline knocking, etc., should be distinguished with acoustic leakage signals to improve the accuracy and reduce false alarms. In this paper, the technologies of extracting characteristics of acoustic signals were summarized. The acoustic leakage signals and interfering signals were measured by experiments and the characteristics of time-domain, frequency-domain and time-frequency domain were extracted. The main characteristics of time-domain are mean value, root mean square value, kurtosis, skewness and correlation function, etc. The features in frequency domain were obtained by… More >

  • Open Access


    Mechanical Response Analysis and Safety Assessment of Shallow-Buried Pipeline under the Influence of Mining

    Zhengzheng Cao1, Yuejin Zhou1,2, Ping Xu1, Jiawei Li1

    CMES-Computer Modeling in Engineering & Sciences, Vol.101, No.5, pp. 351-364, 2014, DOI:10.3970/cmes.2014.101.351

    Abstract In accordance with the influence of underground mining on the deformation and failure of a shallow-buried gas pipeline, the pipe-soil interaction during mining is classified into two stages, namely coordinated deformation stage and partial hanging stage. According to the mechanical characteristics of the buried pipeline in each stage, the models of a) a beam on an elastic foundation, b) an elastic beam under uniform load, and c) a vertical and horizontal bending beam are introduced in a mining subsidence zone to mechanically analyze, respectively a) the pipeline in non-mining subsidence zone, b) the pipeline at the coordinated deformation stage, and… More >

  • Open Access


    CFD and Experimental Investigations of Drag Force on Spherical Leak Detector in Pipe Flows at High Reynolds Number

    ShiXu Guo1, Shili Chen1, Xinjing Huang1, Yu Zhang1, Shijiu Jin1

    CMES-Computer Modeling in Engineering & Sciences, Vol.101, No.1, pp. 59-80, 2014, DOI:10.3970/cmes.2014.101.059

    Abstract Spherical leak detectors can detect very tiny leakage in pipelines and have low risk of blockage. In this paper the passing ability of the detector in the vertical segment of a pipe was studied using CFD simulations and experiments. The Reynolds number for the sphere exceeds 104 at the economical velocity range for oil pipelines, and there were few researches related to the hydrodynamic force on the sphere by the pipe flow at high Reynolds number. For sphere with different sizes and density, and at different flow rates, more than 100 3-D steady numerical simulations were carried out. The simulation… More >

  • Open Access


    A Line Model-Based Fast Boundary Element Method for the Cathodic Protection Analysis of Pipelines in Layered Soils

    L.Q. Liu1, H.T. Wang1,2

    CMES-Computer Modeling in Engineering & Sciences, Vol.90, No.6, pp. 439-462, 2013, DOI:10.3970/cmes.2013.090.439

    Abstract A line model-based fast boundary element method (BEM) is presented for the large-scale cathodic protection (CP) analysis of three-dimensional pipelines in layered soils. In this approach, pipelines are treated as lines with potentials assumed constant over the cross-section and the boundary integrals happen on the associated cylindrical surfaces. The advantage of this model is that pipelines can be meshed with line elements while the boundary integrals are based on the original shapes. Therefore, the number of unknowns is significantly reduced with accuracy effectively retained. A unified formulation of the multipole moments is developed for the mixed boundary element types in… More >

  • Open Access


    Three Dimensional Wave Scattering by Rigid Circular Pipelines Submerged in an Acoustic Waveguide

    António Tadeu, Andreia Pereira, Luís Godinho1

    CMES-Computer Modeling in Engineering & Sciences, Vol.2, No.1, pp. 49-62, 2001, DOI:10.3970/cmes.2001.002.049

    Abstract The Boundary Element Method (BEM) is used to compute the three-dimensional variation pressure field generated by a point pressure source inside a flat waveguide channel filled with a homogeneous fluid, in the presence of infinite rigid circular pipelines. The problem is solved in the frequency domain, using boundary elements to model the pipeline and an appropriate Green's function to simulate the free surface and the rigid floor of the channel. Because of the 2 ---1/2 ---D geometry of the problem, the separation of variables has been used, and the solution at each frequency is expressed in terms of waves with… More >

Displaying 31-40 on page 4 of 42. Per Page