Modeling and Simulation for PIG Flow Control in Natural Gas Pipeline

  • 발행 : 2001.08.01

초록

This paper deals with dynamic analysis of Pipeline Inspection Gauge (PIG) flow control in natural gas pipelines. The dynamic behaviour of PIG depends on the pressure differential generated by injected gas flow behind the tail of the PIG and expelled gas flow in front of its nose. To analyze dynamic behaviour characteristics (e.g. gas flow, the PIG position and velocity) mathematical models are derived. Tow types of nonlinear hyperbolic partial differential equations are developed for unsteady flow analysis of the PIG driving and expelled gas. Also, a non-homogeneous differential equation for dynamic analysis of the PIG is given. The nonlinear equations are solved by method of characteristics (MOC) with a regular rectangular grid under appropriate initial and boundary conditions. Runge-Kutta method is used for solving the steady flow equations to get the initial flow values and for solving the dynamic equation of the PIG. The upstream and downstream regions are divided into a number of elements of equal length. The sampling time and distance are chosen under Courant-Friedrich-Lewy (CFL) restriction. Simulation is performed with a pipeline segment in the Korea gas corporation (KOGAS) low pressure system. Ueijungboo-Sangye line. The simulation results show that the derived mathematical models and the proposed computational scheme are effective for estimating the position and velocity of the PIG with a given operational condition of pipeline.

키워드

참고문헌

  1. Azevedo L. F. A., Braga A. M. B., Nieckele A. O., Naccache M. F., and Gomes M. G. F. M., 1996, 'Simple Hydrodynamic Models for the Prediction of Pig Motions in Pipelines,' Proceeding of the 1996 Offshore Technology Conference, TX., USA, pp. 729-739
  2. Cordell J. and Vanzant H., june 1999, 'All About Pigging,' On-Stream Systems Limited and Hershel Vanzant & Associates
  3. Fox J.A., 1977, Hydraulic Analysis of Unsteady Flow in Pipe Networks, John Wiley & Sons Pub
  4. Hodge B.K. and Koenig K., 1995, Compressible Fluid Dynamics with Personal Computer Applications, Prentice-Hall, Inc., pp. 435-488
  5. Kentfield J. A. C., 1993, 'Nonsteady,One Dimensional Internal,Compressible Flows : Theory and Applications,' Oxford University Press, pp. 33-118
  6. Korea Gas Corporation, March 2000, 'The First Stage of Development of Intelligent PIG for Low Pressure Pipeline'
  7. Lima P. C. R., etrobas Petrobas, and Yeoung H., 1999, 'Modeling of Pigging Operations,' Proceedings of SPE Annual Technical Conference and Exhibition, TX., USA, pp. 563-578
  8. Nguyen T. T., Yoo H, R., Rho Y. W., and Kim S. B., October 2000, 'Modeling and Simulation for PIG Flow Control in Natural Gas Pipeline,' Proceedings of the 15th KACC, pp. 448-
  9. Out J. M. M., 1993, 'On the Dynamics of Pigslug Tranis in Gas Pipeline,' OMAE Pipeline Technology, ASME, Vol. V, pp. 396-403
  10. Pric G. R., McBrien R. K., Rizopoulous S. N., Golshan H., May 1999, 'Evaluating the Effective Friction Factor and Overall Heat Transfer Coefficient During Unsteady Pipeline Operation,' Journal of Offshore Mechanics and Arctic Engineering, ASME, Vol. 121, pp. 131-13665
  11. Sim W. G. and Park J. H., 1997, 'Transient Analysis for Compressible Fluid Flow in Transmission Line by the Method of Characteristics,' KSME International Journal, Vol. 11. No. 2, pp. 173-185
  12. Tannehill J. C., Anderson D. A., and Pletcher R. H., 1997, Computational Fluid Mechanics and Heat Transfer, Taylor & Francis Pub
  13. White F. M., 1999, Fluid Mechanics, McGraw-Hill Pub
  14. Wylie E. B., Steeter V. L. and Suo L., 1993, Fluid Transients in Systems, Prentice-Hall, Inc
  15. Zwillinger D., 1996, 'Standard Mathematical Tables and Formulae,' CRC Press, pp. 716-717