A Numerical Procedure to Estimate Sand Erosion in Elbows for Annular-Mist Flow Based on Film Thickness and Droplet Diameter Prediction

A numerical procedure is proposed in this study to estimate sand particle erosion in elbows for annular-mist flow. This procedure aims at predicting the erosion rates for annular-mist flow conditions as well as overcoming disadvantages of current empirical or semi-empirical models. First, two liquid film thickness correlations and three droplet mean diameter prediction models are examined by comparing the calculated results with experimental data available from the literature, respectively. Second, a numerical prediction procedure is developed based on the information of film thickness and droplet diameter verification. Three different treatments are respectively made on the gas-liquid flow field simulation and fully coupling is adopted for the sand particle tracking. Penetration rates are then calculated by introducing a solid particle erosion correlation, based on the knowledge of flow modeling and particle tracking. Third, four empirical or semiempirical erosion prediction models are introduced to make a comparison with the numerical procedure by verifying predicted results with corresponding experimental data. It indicates that Henstock and Hanratty's film thickness correlation is more efficient and the droplet diameter model by Kocamustafaogullari et al. is the most accurate. Among the four erosion models, the one by Salama shows the best stability and efficiency. The numerical procedure produces good agreement between predicted erosion rates and experimental data.