Numerical simulation considering the impact of proppant and its embedment degree on fracture flow conductivity

The present experimental studies always focus on the impact of proppant particle size, proppant concentration and embedment degree on the fracture flow conductivity, while few studies on the corresponding theoretical calculation model, which, however, can make the fracture project design more reasonable and reliable to improve the success rate of the construction and achieve the expected reservoir stimulation effect. To this end, a numerical calculation model was established considering the flow conductivity of the propped fracture embedded by the proppant on the rock surface according to the Carman Kozeny Formula. Fitting correction was also conducted for this theoretical model based on experimental data, and then the model was used to calculate the fracture flow conductivity respectively of 20-40 meshes, 30-50 meshes and 40-70 meshes proppant under different paved layers and embedment degrees, the influence of which were also discussed. The results show that the larger the proppant particle size and the more paved layers, the higher the flow conductivity. As for the single paved layer, when the embedment degree increased from 0 to 33%, the flow conductivity decreased by 85%. The established model provides a reference to and a basis for particle size selection and sand ratio optimization of multiple reservoirs including tight oil and shale gas. It is also a theoretical model for the further software study considering proppant embedment.