Influence of entrapped air pockets on hydraulic transients in water pipelines

  title={Influence of entrapped air pockets on hydraulic transients in water pipelines},
  author={Ling Zhou and Deyou Liu and Bryan W Karney and Qinfen Katherine Zhang},
  journal={Journal of Hydraulic Engineering},
The pressure variations associated with a filling undulating pipeline containing an entrapped air pocket are investigated both experimentally and numerically. The influence of entrapped air on abnormal transient pressures is often ambiguous because the compressibility of the air pocket permits the liquid flow to accelerate but also partly cushions the system, with the balance of these tendencies being associated with the initial void fraction of the air pocket. Earlier experimental research… 

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