The hydrodynamic effects of single-phase flow on flow accelerated corrosion in a 90-degree elbow

Abstract The hydrodynamic effects of single-phase flow on flow accelerated corrosion (FAC) in a single 90-degree elbow were investigated at a Reynolds number of 40,000. Experiments were performed to determine the surface wear patterns using elbows fabricated from hydrocal. The time evolution of the local surface wear was quantified using a laser scanning coordinate measurement system. Numerical simulations for the flow field were performed, and the wear patterns were correlated to the flow structures within the elbow. The wear patterns indicated the development of surface wear in the form of scallops over most of the elbow surface. Elevated levels of wear were found along the inlet of the elbow intrados. Along the elbow extrados, increased levels of wear, starting from 37° downstream of the elbow inlet and up to the elbow exit, were found at prolonged test times. The magnitude of the maximum wear on the surface along the elbow inner radius was found to be approximately 37% higher than the corresponding value at the surface along the outer radius.

[1]  Marco Enrico Ricotti,et al.  Evaluation of erosion–corrosion in multiphase flow via CFD and experimental analysis , 2003 .

[2]  S. Shirazi,et al.  A Comprehensive Procedure to Estimate Erosion in Elbows for Gas/Liquid/Sand Multiphase Flow , 2006 .

[3]  H. Fiedler A note on secondary flow in bends and bend combinations , 1997 .

[4]  Mahesh D. Pandey,et al.  A probabilistic model of wall thinning in CANDU feeders due to flow-accelerated corrosion , 2008 .

[5]  S. Nešić,et al.  Prediction of two-phase erosion-corrosion in bends , 1999 .

[6]  B. Poulson,et al.  The local enhancement of mass transfer at 180° bends , 1988 .

[7]  Ying Zheng,et al.  Surface Dissolution and the Development of Scallops , 2005 .

[8]  N. Crawford,et al.  An experimental investigation into the pressure drop for turbulent flow in 90° elbow bends , 2007 .

[9]  A. Spence,et al.  Laser digitizer-based sheet metal strain and surface analysis , 2007 .

[10]  Y. Ferng,et al.  Numerically Investigating the Influence of Local Flow Behaviors on Flow-Accelerated Corrosion Using Two-Fluid Equations , 1998 .

[11]  B. Poulson Complexities in predicting erosion corrosion , 1999 .

[12]  G. Sedahmed,et al.  The role of mass transfer in the flow-induced corrosion of equipments employing decaying swirl flow , 2002 .

[13]  M. Sumida,et al.  Experimental investigation on turbulent flow in a square-sectioned 90-degree bend , 1998 .

[14]  Srdjan Nesic,et al.  Using computational fluid dynamics in combating erosion-corrosion , 2006 .

[15]  R. B. Dooley,et al.  Flow-accelerated corrosion in fossil and combined cycle/HRSG plants , 2008 .