EFFECTS OF TWO-DIMENSIONALITY ON PIPE TRANSIENTS MODELING

The authors discuss the rapid damping of pressure peaks in a water-hammer phenomenon after the end of a complete valve-closure maneuver. When one-dimensional models are used, this effect is not apparent because certain flow characteristics are not considered. The effect is tied to the cross-sectional velocity profiles, and therefore, to the intrinsic two-dimensionality of the flow field. By applying a recently proposed two-dimensional model to expand the limited experimental data available with numerical results, useful information on the evolution of the velocity profiles during a transient is obtained. An additional term is introduced into the momentum equation to model the effects of the flow-field two-dimensionality in a one-dimensional formulation. And finally, the adequacy of a relationship previously offered by the authors to evaluate the added term is specifically shown for fast transients in the field of low-Reynolds-number flows when no cavitation occurs, even if its validity is proven elsewhere under different conditions.

Language

  • English

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00715317
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jan 8 1996 12:00AM