Add abstract
Want to add your dissertation abstract to this database? It only takes a minute!
Search abstract
Search for abstracts by subject, author or institution
Want to add your dissertation abstract to this database? It only takes a minute!
Search for abstracts by subject, author or institution
Assessment of zonal isolation risk to changes in design parameters
by Huidong active Zhang
Institution: | University of Texas Austin |
---|---|
Year: | 2017 |
Keywords: | Zonal isolation risk; Quantitative risk analysis |
Posted: | 02/01/2018 |
Record ID: | 2220538 |
Full text PDF: | http://hdl.handle.net/2152/62684 |
The Well Containment Screening Tool (WCST) focuses on well integrity evaluation after well control incident. The WCST favors a greater wall thickness and, hence, a narrower cementing annulus, potentially increasing the risk of cement loss. We develop a structured and systematic physical model to simulate and track formation damage. A simulation process is conducted to assess the sensitivity of zonal isolation risk as design parameters are changed. In this paper, a physical model involving wellbore, casing and cement fluid is developed to understand the interaction between cement fluid and the formation. Two failure metrics are defined that provide a comprehensive understanding of the zonal isolation risk. Quantitative risk assessment is implemented with Monte Carlo simulation to assess the risk of zonal isolation problems when design parameters are changed. Models of production casing and intermediate casing are studied to verify the generality of this analysis. Taking both failure metrics into consideration, sensitivity analysis for models of production casing and intermediate casing present common observations regarding changes of design parameters. Our analysis suggests that minor increases (within 0.05) in casing thickness, due to increased outer diameter, has little influence on the risk of cement loss, as does slight decreases in mean open hole diameter (within 0.05). To verify the generality of this approach, in addition to casing and wellbore parameters, the sensitivity to cement fluid flow rate is analyzed. We find that risk is not significantly affected by small increase of flowrate (e.g. from 40 to 100 gpm). This paper applies a novel quantitative risk analysis to assess the influence of different design parameters on zonal isolation problems. This approach, if well implemented, can help to assess the impact of changes in design parameters (e.g., casing length and depth, mud density and cement fluid density, etc.) on drilling safety. It can also help to inform drilling decisions by providing forecasts of zonal isolation risk for particular geological condition.Advisors/Committee Members: Bickel, J. Eric (advisor), van Oort, Eric (committee member).
Want to add your dissertation abstract to this database? It only takes a minute!
Search for abstracts by subject, author or institution
Electric Cooperative Managers' Strategies to Enhan...
|
|
Bullied!
Coping with Workplace Bullying
|
|
The Filipina-South Floridian International Interne...
Agency, Culture, and Paradox
|
|
Solution or Stalemate?
Peace Process in Turkey, 2009-2013
|
|
Performance, Managerial Skill, and Factor Exposure...
|
|
The Deritualization of Death
Toward a Practical Theology of Caregiving for the ...
|
|
Emotional Intelligence and Leadership Styles
Exploring the Relationship between Emotional Intel...
|
|
Commodification of Sexual Labor
Contribution of Internet Communities to Prostituti...
|
|
The Census of Warm Debris Disks in the Solar Neigh...
|
|
Risk Factors and Business Models
Understanding the Five Forces of Entrepreneurial R...
|
|