Finite Element Modeling of Particle Failure in Stressed Particle Beds

Open Access
Author:
Harris, Jason Thomas
Graduate Program:
Engineering Mechanics
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
April 04, 2008
Committee Members:
  • Albert Eliot Segall, Thesis Advisor
Keywords:
  • proppant
  • CCP
  • FEA
  • Finite element
  • particle failure
Abstract:
Proppants are used in oil and natural gas extraction to maintain the permeability of the well after the opening pressure is released. In order to optimize proppant life and bed permeability, a comprehensive methodology was developed that includes relevant assessment of stresses and a material’s ability to resist them. Accordingly, the study first focused on the stresses associated with particle interactions while under mechanical and fluid loads associated with oil and natural gas extraction. A close-cubic pack finite-element model was employed during this evaluation. In order to apply the aforementioned finite-element model to the API 60 compaction test, the area and volume independent characteristic strengths and the pressure distribution in the test cell needed to be evaluated. Strengths of proppants were first evaluated experimentally by the diametral compression test. The specimen strengths were then scaled via a finite-element model and the CARES parameter estimation software. A ball-on-ring finite element model was also developed to scale strengths evaluated from the ball-on-ring test. An exponential decay pressure distribution was also found to representative of the pressure distribution in the test cell. After the procedure was developed to directly compare experimental and finite element results, the model was verified using glass proppants. An API 60 test was first completed. With the number of failed proppants measured and the failure probability determined. However, a portion of the survived proppants were analyzed and found to contain flaw or failures that left particles too large to be filtered out. Once the extra failed proppants were included, the experimental data was found to compare well with the finite-element results. After verification, the model can be used to evaluate potential proppants and possibly tailor proppant designs.