Grand Round Case - Multiple Pulmonary Infarcts and Reversible Left Ventricular Dysfunction in a Patient with Chronic Heart Disease

no abstrac

Development of a combined Euler-Euler Euler-Lagrange slurry model

There has been a significant amount of work on modelling erosion caused by slurries, however, these studies are normally focused on low concentrations. The reason for this is usually that dense slurries are too computationally expensive to model in the Euler-Lagrange frame. This presentation suggests a novel solution for reducing computational effort using OpenFOAM to combine two solvers. The two phases of the bulk flow are modelled, partially in the Eulerian-Eulerian reference frame, and partially in the Eulerian-Lagrangian frame. The method aims to increase computational efficiency, but still keep the necessary particle impact data at the wall required for erosion modelling. The new model consists of splitting the domain into two regions and using patch interpolation to couple them together. The particles are then injected into the second region by using the values of the second Eulerian phase from the first region. The values of the second Eulerian phase are written at every time step to a lookupTable, enabling the solver to be used in conjunction with geometry changes, etc., as in Lopez’s work (Lopez in LPT for erosion modelling in OpenFOAM 2014, [1]). If the process can be validated, it provides a promising step towards modelling dense slurry erosion

Assessing the influence of shear stress and particle impingement on inhibitor efficiency through the application of in-situ electrochemistry in a CO-saturated environment

An investigation was conducted to assess the performance of a commercially available high shear carbon dioxide (CO) corrosion inhibitor in a series of flow-induced corrosion and erosion-corrosion environments. The purpose of the study was to understand the role that high shear stress and sand particle impingement play in influencing the in-situ corrosion rate of API 5L X65 carbon steel in blank and inhibited conditions. Tests were conducted at 45°C in CO-saturated conditions using a rotating cylinder electrode (RCE) for low shear stress tests (18-260Pa) and a submerged impinging jet (SIJ) for high shear environments (104-740Pa). The inhibitor was studied at concentrations of 0, 25, 50, 75 and 100ppm. The application of computational fluid dynamics to model the SIJ and the use of ring shaped samples allowed for an accurate prediction of shear stress across the specimen surface that could be correlated with in-situ corrosion rate and inhibitor efficiency over a range of concentrations. The incorporation of 500mg/L of sand to the system helped to quantify the increase of the in-situ corrosion rate due to the impingement of the particles. All corrosion rates were determined through the application of linear polarization measurements throughout the duration of the test. Post-test analysis of the material degradation mechanisms was examined using scanning electron microscopy (SEM)