Alf Kristian Gjerstad

S. Tamaddon; Kristian Gjerstad (2025) Estimating Hole Cleaning Efficiency in Real-Time by Combining Along String Measurements and Hydraulic Modelling. I: IADC/SPE International Drilling Conference and Exhibition. ISSN 2691-0926. DOI: https://dx.doi.org/10.2118/223791-MS

Masoumeh Amiri Mikal; Arild Saasen; Mahmoud Khalifeh; Kristian Gjerstad (2025) Rheological Behavior of Bentonite-Water Mud Under Elevated Temperatures : Predicting Fluid Performance. I: Annual Transactions - The Nordic Rheology Society. ISSN 1601-4057. Volum 33. s.95-102. DOI: 10.31265/atnrs.869

Kristian Gjerstad (2025) Revealing Time-Dependent Mud Properties Needed for Predicting Gel Breaking Pressure. I: Society of Petroleum Engineers SPE, SPE/IADC International Drilling Conference and Exhibition, March 4–6, 2025. Society of Petroleum Engineers. ISBN 9781959025641. DOI: 10.2118/223704-ms

Kristian Gjerstad (2024) Water density–pressure–temperature modeling for drilling fluids in real-time HPHT applications. I: Geoenergy Science and Engineering. ISSN 2949-8929. Volum 244. DOI: 10.1016/j.geoen.2024.213420

Peter Shipton; Mohamed Amish; Kristian Gjerstad (2023) Using Transient Modeling to Define the Effects of Heave on Wellsite Operations. I: SPE Drilling & Completion. ISSN 1064-6671. Volum 38. s.486-501. DOI: 10.2118/214691-PA

Kristian Gjerstad (2023) Relating stress-overshoot measurements of drilling fluids to rheological properties by utilizing inertia calculations, oscillatory tests and modelling. I: Alex Babanin; Hayden Marcollo, ASME 2023 42nd International Conference on Ocean, Offshore and Arctic Engineering : Volume 2: Structures, Safety, and Reliability. The American Society of Mechanical Engineers (ASME). ISBN 9780791886847. DOI: 10.1115/OMAE2023-105303

Jahanzaib Mazhar; Muhammad Usman; Kristian Gjerstad (2022) Analysis of Gelling Properties of Drilling Fluid and Improved Modelling of Gelling Behaviour. I: Herimonja Andrianifaliana Rabenjafimanantsoa, Annual Transactions the Nordic Rheology Society. Nordic Rheology Society. ISBN 9788269272123. s.99-110. https://hdl.handle.net/11250/4510270

Alf Kristian Gjerstad; Ole Morten Aamo (2021) A dynamic model of two-phase flow for simulating gas kick and facilitating model-based control in drilling operations. I: Journal of Petroleum Science and Engineering. ISSN 0920-4105. Volum 205. s.1-17. DOI: 10.1016/j.petrol.2021.108902

Benoit Daireaux; Adrian Ambrus; Liv Carlsen; Rodica G. Mihai; Alf Kristian Gjerstad; Mohsen Karimi Balov (2021) Development, Testing and Validation of an Adaptive Drilling Optimization System. I: Society of Petroleum Engineers SPE, IADC/SPE Managed Pressure Drilling & Underbalanced Operations Conference & Exhibition, Virtual, September 2021. Society of Petroleum Engineers. ISBN 9781613997420. DOI: 10.2118/204083-MS

Alf Kristian Gjerstad; Rune Wiggo Time (2015) Simplified explicit flow equations for Herschel–Bulkley fluids in Couette–Poiseuille flow - For real–time surge and swab modelling in drilling. I: SPE Journal. ISSN 1086-055X. Volum 20. s.610-627. DOI: 10.2118/170246-PA

Kristian Gjerstad, Rune Wiggo Time (veileder), Birger Erik Ydstie (veileder). (2014). Simplified Flow Equations for Single-Phase non-Newtonian Fluids in Couette-Poiseuille Flow and in Pipes : For Dynamic Modeling of Surge and Swab Pressure in Oil Well Drilling Operations. Universitetet i Stavanger. ISBN 9788276445695. https://hdl.handle.net/11250/5525621

Alf Kristian Gjerstad; B.Erik Ydstie; Rune Wiggo Time; Knut Steinar Bjørkevoll (2013) An Explicit and Continuously Differentiable Flow Equation for Non-Newtonian Fluids in Pipes. I: SPE Journal. ISSN 1086-055X. Volum 19. s.78-87. DOI: 10.2118/165930-PA

Alf Kristian Gjerstad (2012) Simplified Modelling of Downhole Pressure Surges for Bingham Fluids in Tripping Operations. I: Society of Petroleum Engineers SPE, SPE Annual Technical Conference and Exhibition, 8-10 October 2012, San Antonio, Texas, USA. Society of Petroleum Engineers. ISBN 9781613992135. https://hdl.handle.net/11250/3675180

S. Tamaddon; Kristian Gjerstad (2025) Estimating Hole Cleaning Efficiency in Real-Time by Combining Along String Measurements and Hydraulic Modelling. SPE/IADC International Drilling Conference and Exhibition, Stavanger; 2025-03-03 - 2025-03-05. DOI: 10.2118/223791-ms

Kristian Gjerstad (2023) Relating Stress-Overshoot Measurements Of Drilling Fluids To Rheological Properties By Utilizing Inertia Calculations, Oscillatory Tests And Modelling. 42nd International Conference on Ocean, Offshore & Arctic Engineering; 2023-06-11 - 2023-06-16. https://hdl.handle.net/11250/4135836

Jahanzaib Mazhar; Kristian Gjerstad; Mohammad Usman (2022) Analysis of gelling properties of drilling fluid and improved modelling of gelling behaviour. The Nordic Rheology Conference 2022; 2022-10-08 - 2022-10-10. https://hdl.handle.net/11250/4035889

Kristian Gjerstad; Ronny Bergerud; Stig Tore Thorsen (2020) Exploiting the Full Potential in Automated Drilling Control by Increased Data Exchange and Multi Disciplinary Collaboration. SPE Annual Technical Conference & Exhibition; 2020-10-05 - 2020-10-07. https://hdl.handle.net/11250/4225120

John Kenneth Hatletvedt; Kristian Gjerstad; Jing Zhou (2018) Modelling of a Hydro-Pneumatic System for Heave Compensation. IEEE Conference on Industrial Electronics and Applications (ICIEA); 2018-05-31 - 2018-06-02. https://hdl.handle.net/11250/3745703