A new automatic differentiation approach for fully implicit compositional reservoir simulation
by Bruno Ramon Batista Fernandes; Francisco Marcondes; Kamy Sepehrnoori
International Journal of Oil, Gas and Coal Technology (IJOGCT), Vol. 34, No. 2, 2023

Abstract: A new stand-alone object-oriented automatic differentiation (AD) tool for FORTRAN 95 codes is presented for facilitating the development of implicit solutions of PDEs. Five different AD approaches were implemented and tested: a forward mode (FM) with static allocation, an FM with dynamic allocation and memory stack, an expression-level reverse mode (RM) with memory stack, an expression-level RM with pointers, and a fully RM with pointers. The new tool is applied to an in-house chemical enhanced oil recovery simulator using three approaches: seed matrix, localised linearisation, and using AD only for computing gridblock properties. The FM AD with static allocation was the fastest AD approach but didn't have the flexibility for problems with variable gradient size. Among the AD coupling techniques, the localised linearisation presented a better performance for assembling the Jacobian when compared to the seed matrix scheme. The use of AD for computing properties only presented the smallest overhead. [Received: May 10, 2023; Accepted: June 1, 2023]

Online publication date: Tue, 03-Oct-2023

The full text of this article is only available to individual subscribers or to users at subscribing institutions.

 
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.

Pay per view:
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.

Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Oil, Gas and Coal Technology (IJOGCT):
Login with your Inderscience username and password:

Username:        Password:          Forgotten your password?

Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.

If you still need assistance, please email subs@inderscience.com