• Title/Summary/Keyword: Pipeline system

Search Result 778, Processing Time 0.034 seconds

Transient Analysis and Experiment Considering Unsteady Friction and Leakage in a Pipeline System (단일관망에서 누수효과를 고려한 천이류 분석 및 실험)

  • Lee, Mi-hyun;Song, Yong-sok;Kim, Sang-hyun
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.20 no.2
    • /
    • pp.207-214
    • /
    • 2006
  • The current paper focuses the analysis of leakage detection in water pipeline systems by means of the transient method. In order to obtain essential data for evaluation the existing methodology, an extensive experimental process has been carried out in a single pipeline system, Several experimental tests were performed with and without a leakage in the system. Using the unsteady friction and improved unsteady friction factors gives reasonable match between the computed and measured results on the condition of the flow situations presented in the paper. The transient method attempts to estimate the leakage in water pipelines using observed pressure data collected during transient events on the system.

Unsteady Flow Rate Measurement by Using Hydraulic Pipeline Dynamics (유압관로의 동특성을 이용한 비정상 유량계측)

  • 김도태
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 1999.10a
    • /
    • pp.411-416
    • /
    • 1999
  • The measurement of unsteady flow rate is of vital importance to clarify and improve the dynamic characteristics in pipeline, hydraulic components and system. There is also demand for a real time flow sensor of ability to measure unsteady flow rate with high accuracy and fast response to realize feedback control of flow rate in fluid power systems. In this paper, we propose an approach for estimating unsteady flow rate through a pipeline and components under high pressure condition. In the method, unsteady flow rate is estimated by using hydraulic pipeline dynamics and the measured pressure values at two distant points along the pipeline. The distributed parameter model of hydraulic pipeline is applied with consideration of frequency dependent viscosity friction and unsteady velocity distribution at a cross section of a pipeline. By using the self-checking functions of the method, the validity is investigated by comparison with the measured and estimated pressure waveforms at the halfway section on the pipeline. The results show good agreement between the estimated flow rate waveforms and theroetical those under unsteady laminar flow conditions. the method proposed here is useful in estimating unsteady flow rate through an arbitray cross section in hydraulic pipeline and components without installing an instantaneous flowmeter.

  • PDF

The Study about Control Monitoring of Fiber Optic Sensor on Vacuum Pipeline for Waste Collecting System (광섬유센서를 이용한 쓰레기수송관로 유지관리 모니터링에 대한 연구)

  • Lee, Joon-Young;Kim, Chae-Suk;Kim, Bong-Gyu
    • The KSFM Journal of Fluid Machinery
    • /
    • v.13 no.2
    • /
    • pp.54-58
    • /
    • 2010
  • The most recent, Vacuum Pipeline for Waste Collecting System, to collect MSW(Municipal Solid Waste) efficiently, is used environmental preservative, to emit less air pollution, in New City. However, it is difficult to monitor broken pipe and filled mass of Waste, because Vacuum Pipeline is laid underground. Therefore, FBG, optical fiber sensor, is used to inspect the temperature change and longitudinal strain to take proper action for unusual situation. I have need to accumlate sensor data of district control. I hope to be used Vacuum Pipeline more than 30 years in New City.

Leak Detection of Waterworks Pipeline Using Acoustic Emission and Correlation Method (음향방출 및 상관법을 이용한 상수도배관 누수탐지 연구)

  • Yoon, Dong-Jin;Jeong, Jung-Chae;Lee, Young-Sup
    • Proceedings of the KSME Conference
    • /
    • 2003.04a
    • /
    • pp.84-89
    • /
    • 2003
  • Water leak is one of topics with great concern in Korea and many other countries, because of decreasing water supplies and the deterioration of old pipeworks. Correlation techniques have been widely used in leak detection of water pipes, which allow to locate a leak point based on the correlation of leak noise at two sites along water pipes. In this study, both the cross-correlation method and the conventional arrival time difference method are applied in order to analyze and to locate a leak point of a water pipe. In experiment, a 150 m of whole length waterwork pipeline system was constructed in a ground, and several types of leak noise were installed on the pipeline in order to control leak condition. Both the cross-correlation technique and the arrival time difference method showed favorable results at leak detection with the experimental pipeline system.

  • PDF

Internal Pipeline Exploration of an In-pipe Robot Using the Shadow of Pipe Fittings (배관요소 그림자를 이용한 배관로봇의 배관내부 탐사)

  • Lee, Jung-Sub;Lee, Dong-Hyuk;Roh, Se-Gon;Moon, Hyung-Pil;Choi, Hyouk-Ryeol
    • The Journal of Korea Robotics Society
    • /
    • v.5 no.3
    • /
    • pp.251-261
    • /
    • 2010
  • In this paper, we introduce an internal pipeline exploration of an in-pipe robot, based on the landmark recognition system. The fittings of pipelines such as elbows and branches are used as the landmarks. The robot recognizes the landmarks with a vision system by using the shadows of the elements, which are generated by the specially designed illuminator on the robot. By using a simple image-processing, the robot can easily detect and distinguish these landmarks while recognizing the direction of the pipeline path. Simultaneously, all information for exploration is continuously recorded and used to reconstruct the map of the pipelines. The effectiveness of the proposed method is verified by real experiments using the in-pipe robot MRINSPECT V for moving inside of the miniature urban 8-inch gas pipeline structure.

REDUCTION OF PRESSURE RIPPLES USING A PARALLEL LINE IN HYDRAULIC PIPELINE

  • KIM K. H.;JANG J. S.;JUNG D. S.;KIM H. E.
    • International Journal of Automotive Technology
    • /
    • v.6 no.1
    • /
    • pp.65-70
    • /
    • 2005
  • Pressure ripples, which are inevitably generated by a fluctuation of flow rate caused by a pump mechanism, include noises and vibrations in hydraulic pipeline. These noises and vibration deteriorate the stability and accuracy of hydraulic systems. The accumulator and hydraulic attenuator are normally used to reduce the pressure ripples. In this study, a parallel line is introduced to the hydraulic pipeline for the hydraulic system with a bent-axis piston pump as a method to reduce the pressure ripples. The dynamic characteristics of the hydraulic pipeline with a parallel line are analyzed by a transfer matrix in the frequency domain. The usefulness of the hydraulic pipeline with a parallel line was ascertained by experiment and simulation. The results from the experiment and simulation show that the hydraulic pipeline with a parallel line were effective in reducing the pressure ripples.

Study on Transient Flow in Pipeline with Flexible Tube (탄성관을 삽입한 관로에서의 비정상류에 관한 연구)

  • Kim, Young-Joon;Tsukamoto, Hiroshi
    • 유체기계공업학회:학술대회논문집
    • /
    • 2005.12a
    • /
    • pp.825-828
    • /
    • 2005
  • Experimental and numerical study was done to confirm the effect of the flexible tube in pipeline on transient flow oscillation. Experiment was made for a pipeline with and without deformable flexible tube using a single pumping system of main stainless pipe. The wave speeds of main pipe and flexible tube were calculated from the pipe material properties, structures, and boundary conditions. Time dependent pressure fluctuations were calculated for the pipeline using the simple and the Kelvin-Voigt viscoelastic models for the deformation of main pipe and flexible tube. Pressure calculated by the Kelvin-Voigt viscoelastic model showed better agreement with measured one than pressure by the simple model. Experimental and numerical results show that the maximum pressure as well as amplitude of pressure oscillation was decreased by inserting short flexible tube in pipeline. Hence, inserted short flexible tube to pipeline was found to be effective for the suppression of strong pressure oscillation. Moreover, the wave speed in pipe was discussed based on numerical and experimental results.

  • PDF

A pressure based flow velocity estimation technique using inverse impedance for simple pressurized pipeline systems (피압 단순 관로 체제에서의 인버스 임피던스를 이용한 수압기반 유속추정기술)

  • Lee, Jeongseop;Ko, Dongwon;Choi, Dooyong;Kim, Sanghyun
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.36 no.4
    • /
    • pp.219-228
    • /
    • 2022
  • In this study, we propose a flow velocity evaluation scheme based on pressure measurement in pressurized pipeline systems. Conservation of mass and momentum equations can be decomposed into mean and perturbation of pressure head and flowrate, which provide the pressure head and flowrate relationship between upstream and donwstream point in pressurized pipeline system. The inverse impedance formulations were derived to address measured pressure at downstream to evaluation of flow velocity or pressure at any point of system. The convolution of response function to pressure head in downstream valve provides the flow velocity response in any point of the simple pipeline system. Simulation comparison between traditional method of characteristics and the proposed method provide good agreements between two distinct approaches.

A real-time unmeasured dynamic response prediction for nuclear facility pressure pipeline system

  • Seungin Oh ;Hyunwoo Baek ;Kang-Heon Lee ;Dae-Sic Jang;Jihyun Jun ;Jin-Gyun Kim
    • Nuclear Engineering and Technology
    • /
    • v.55 no.7
    • /
    • pp.2642-2649
    • /
    • 2023
  • A real-time unmeasured dynamic response prediction process for the nuclear power plant pressure pipeline is proposed and its performance is tested in the test-loop system (KAERI). The aim of the process is to predict unmeasurable or unreachable dynamic responses such as acceleration, velocity, and displacement by using a limited amount of directly measured physical responses. It is achieved by combining a well-constructed finite element model and robust inverse force identification algorithm. The pressure pipeline system is described by using the displacement-pressure vibro-acoustic formulation to consider fully filled liquid effect inside the pipeline structure. A robust multiphysics modal projection technique is employed for the real-time sensor synchronized prediction. The inverse force identification method is also derived and employed by using Bathe's time integration method to identify the full-field responses of the target system from the modal domain computation. To validate the performance of the proposed process, an experimental test is extensively performed on the nuclear power plant pressure pipeline test-loop under operation conditions. The results show that the proposed identification process could well estimate the unmeasured acceleration in both frequency and time domain faster than 32,768 samples per sec.

Experimental and Numerical Methods for Thermal Conductivity of Backfill Soils for Subsea Pipeline (해저배관 뒤채움 흙의 열전도율 산정에 관한 실험 및 수치 해석적 연구)

  • Park, Dong-Su;Seo, Young-Kyo
    • Journal of Ocean Engineering and Technology
    • /
    • v.31 no.2
    • /
    • pp.103-110
    • /
    • 2017
  • The temperature of subsea pipeline, approximately as high as $100^{\circ}C$, is significantly higher than the temperature of surrounding sea water and sediment. In this reason, heat can be lost from the subsea pipeline to cause serious operation problem. Therefore it is important that the subsea pipeline must be designed to ensure that heat loss is small enough. Heat loss of unburied pipeline is higher than buried pipeline. For that purpose, trenching and backfilling system is a commonly used method for maintaining flow assurance in subsea pipeline installation. For this commonly used method, knowing thermal conductivity of backfill is essential to protect a heat loss of pipeline. This paper presents thermal conductivity of backfill soil using laboratory model test and numerical analysis for various backfill. In conclusion, it can be seen that higher the sand content of the man-made backfill sample, the higher the thermal conductivity. On the other hand, as the water content increases, the thermal conductivity becomes smaller.