OLGA-S 2014 Version 2014.1

Release notes

-S MULTIPHASE FLOW MODEL

Page i

August 2014

INTRODUCTION ................................................................................................................................................ 1

ENHANCEMENTS .............................................................................................................................................. 2

FIXED ISSUES .................................................................................................................................................... 2

OLGA-S 2014.1 Release Notes Page 1

August 2014

INTRODUCTION

OLGA-S is a steady-state point model for multiphase flow in wells and pipelines. It has a one dimensional three fluid model for two-phase hydrocarbon and water flow. OLGA-S is delivered in binary form as a library which can be dynamically linked to a driver program, e.g. a steady-state simulator for pipeline networks.

These notes accompany the release of OLGA-S version 2014.1 from Schlumberger. The notes describe changes to the code, and should be read by all users of the program. The changes listed below are relative to OLGA-S version 7.3.1.

The Schlumberger Support portal provides useful information about the product and a Knowledge Base. It is accessible from www.software.slb.com.

Please contact Schlumberger if problems or missing functionality are encountered when using OLGA-S or any of the related tools included in the OLGA-S software package.

E-mail: olgasupport@slb.com

Telephone: +47 6389 0400

Fax: +47 6484 4500

Address: Schlumberger Information Solutions AS,

P.O. Box 113

N-2027 Kjeller, Norway

Disclaimer: Every effort has been made to supply complete and accurate information, however the information in this document is subject to change without notice. Schlumberger assumes no responsibility for any errors that may occur in the documentation. Please contact olgasupport@slb.com if you have any questions.

OLGA-S 2014.1 Release Notes Page 2

August 2014

ENHANCEMENTS

Multiphase Toolkit

Multiphase Toolkit is a front end for the OLGA-S point model, making it possible to analyse fully developed steady state operating conditions in parts of a pipeline. It can be a useful tool ahead of pipeline simulations to learn about your system, e.g. the prediction of holdup as function of inclination for different production rates. If the angle distribution of a pipeline is known, the liquid content in the pipeline for different production rates can be estimated. Investigation of flow regimes for different conditions (inclination, diameter, flow rates) and flow regime maps can also be useful to gain insight into the flow characteristics in parts of a pipeline.

FIXED ISSUES

Correction in slug flow model

Two bugs have been corrected in the new method for calculating the Taylor bubble front velocity, introduced in OLGA-S 7.3.1. The sign of the bubble drift velocity correlation for high Froude numbers (Fr > 3.5) was incorrectly computed under some circumstances, and an incorrect drift velocity was computed for the case when the Taylor bubble turns against the flow under gravity dominated flow conditions. Both errors have been corrected. The model changes only affects slug flow, but it may indirectly affect other flow regimes since changes in the slug flow predictions may lead to a different flow regime being predicted. It only affects downflow. For most cases there is no or moderate change to the predictions. (OLGA-15803)