APEX-AP1000 Confirmatory Testing To Support AP1000 Design Certification (Non-Proprietary) To Support AP1000 Design Certification (Non-Proprietary) U.S.

Today I also found this more later.

http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1826/  

The above link yields a highly sanitized version of NUREG-1826,  

APEX-AP1000 Confirmatory Testing
To Support
AP1000 Design Certification

Manuscript Completed: June 2005
Date Published: August 2005 

Prepared by
K.B. Welter and S.M. Bajorek
Advanced Reactors and Regulatory Effectiveness Branch
Division of Systems Analysis and Regulatory Effectiveness
Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

 and

Jose Reyes, Jr., Brian Woods, John Groome, John Hopson,
Eric Young, John DeNoma, and Kent Abel
Department of Nuclear Engineering
Institute of Thermal-Hydraulics
Oregon State University
Corvallis, OR 97601
Gene S. Rhee, NRC Project Manager 

 I'm not reviewing that document here, but it refers to drift-flux only twice, pages 167 and 168 of 280.

 The void fraction as a function of position in the core was obtained using the drift-flux
relationship [Ref. 15]:

and 

The churn-turbulent drift-flux correlation was used to assess equation (A.157) for both APEX and AP1000. 

However, as I scan the document, I see no consideration of the impact of boric acid on the drift-flux considerations.  For example