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The goal of this project was to demonstrate the potential of an HPC solution to model perforation erosion and the resulting pressure drop. The model was to be based upon first principals requiring no additional experimental data besides material properties. The software is to automate the calculation of erosion and flow characteristics thereby allowing application to reservoir/hydraulic-fracturing simulators in order to optimize fracturing treatment and diversion agent strategy. Reservoir and wellbore properties will be adjustable by the user, based on the results of common industry testing and methods (e.g., core analysis, standard wireline and image logging, LWD, DFIT …) that are available to the completions’ engineers performing the frac work. During primary hydraulic stimulation of long horizontal wells, discrete segments (referred to as stages) are connected to the formation with shaped charges (perforations). There can also be – and likely are – natural fractures intersecting the wellbore and the clusters. The perforation clusters are concurrently available for creating multiple hydraulic fractures. The natural fractures can also be preferential pathways for hydraulic stimulation. This multiplicity of fractures is desirable because it increases the surface area of conductive pathways connected to the wellbore – enabling production from low permeability formations. As indicated, connectivity between the reservoir and the wellbore is usually created with shaped charges (perforations) in the discrete clusters. Hydraulic and other boundary conditions often favor the predominant growth of one fracture at the expense of growing a number of fractures. This biasing worsens due to erosion of the perforations in casing and surrounding materials. This nonuniform stimulation, worsened by erosion, substantially reduces the recovery of hydrocarbons. The consequences of sub-optimal hydraulic fracturing can be millions of dollars in operational expenditures compounded by even larger future losses associated with impaired recoveries and diminished reserves. These effects are compounded when using the limited entry technique, or any case where 1) the number of perforations is limited, 2) there is large injection rate/significant proppant, and/or there is large variety in formation stress. It has been demonstrated that perforation erosion plays a significant role in hydraulic-fracturing stimulation treatments. However, erosion can be affected with perforation-cluster spacing, number, fracturing-fluid, treatment, and diversion agents. Any mitigation requires detailed understanding of the erosion and subsequent effect on fracturing. Perforation erosion changes flow distribution by affecting the pressure drop through perforation caused by changes in local geometry. This primarily consists of two geometric changes, rounding/smoothing of the perforation entrance and increase of the perforation diameter. However, these effects are often neglected or under-modeled in reservoir and hydrologic-fracturing simulators. Traditionally, the Bernoulli equation has been used by the industry to estimate perforation pressure drop and flow. However, these correlations require assumptions about the geometry, fluid properties, material properties, and flow characteristics. Due to these assumptions, the correlations must be calibrated with additional experimental data for each combination. As a result of this complexity, erosion is often neglected in reservoir/hydraulic-fracturing simulators and if modeled, simplified corrections are utilized. The results of this Phase I effort demonstrated the potential of utilizing the Uintah::MPMICE code for predicting the erosion and pressure drop occurring from flow of proppant slurry through downhole perforations. Comparisons with available pressure drop data showed the approach to agree better with the data then recent correlations in the literature.