Schlumberger OLGA 2026.1.0

Olga动态多相流模拟器可模拟瞬态流动（随时间变化的行为），从而最大限度地提高生产潜力。瞬态建模是可行性研究和油田开发设计的重要组成部分。动态模拟在深水环境中至关重要，并广泛应用于海上和陆上开发项目中，用于研究管道和井筒中的瞬态行为。Olga模拟器的瞬态模拟通过预测系统动态（例如流量、流体成分、温度、固体沉积和操作变化等随时间的变化）为稳态分析增添了新的维度。Olga模拟器能够精确预测整个生产系统中的瞬态流动行为——从井筒动态到完井，再到管道和相关工艺设备。

可用版本: 2026.x , 2025.x ,…

Schlumberger OLGA 2026.1.0 Tested Picture

As part of our ongoing commitment to excellence, we continuously innovate to enhance our product. This latest version brings multiple improvements, updates, and bug-fixes to benefit our users. The most important improvements are mentioned in this document below. Please read the release notes for the full overview.

Update of Symmetry Library

The latest Symmetry™ fluid engine release brings major stability and accuracy improvements for Olga compositional tracking and Symmetry flashes. Key highlights include:

• Masked floating-point exceptions and corrected phase identification for gas–aqueous systems.
• Enhanced pressure-enthalpy (P-H)-flash handling with consistent schemes for pressure-temperature (P–T) and PH flashes, ensuring stable density derivatives.
• Fixes for internal flashes in inert and simplified three-phase cases when fluids are pure water or aqueous compounds.
• Improved vapor-liquid equilibrium (VLE) predictions for CO₂–natural gas mixtures and better P-H-flash solutions for low-boiling-point fluids.

Update of Multiflash Library

The KBC Multiflash library has been upgraded from 7.5 to 7.6, delivering improved accuracy and robustness for compositional tracking simulations. Highlights include:

• Enhanced advanced cubic EOS model with updated binary interaction parameters (BIPs) and component properties for better accuracy.
• More robust extrapolation near the critical point for continuous property predictions (notably heat capacity and enthalpy).
• Faster model initialization and updated EOS-CG (Combustion Gas) to the latest 2021 publication.
• Improved handling outside validity ranges with a fallback cubic EOS method, while high-accuracy aqueous EOS remains active for tracking.

Additional improvements:

• Better viscosity tuning with Pedersen and LBC models.
• Updated mercury model. Licenses will be available through SLB.
• Added THF and carbon monoxide as hydrate formers.

Update of PVTSim Library

The latest PVTSim Nova 7.2 release introduces key enhancements for Olga simulator integration:

• Compositional tracking with PH Flash is now supported.
• New option in the Olga tab file interface lets users control liquid–liquid splits. When two non-aqueous liquid phases occur (e.g. two hydrocarbons or a hydrocarbon and CO₂-rich phase), you can choose to merge them into one liquid or treat the lighter phase as gas in the tab file.
• Ability to generate Olga PH tab files in both PVTSim Nova and PVTSim Nova CCS.

Directional leak functionality

The new directional leak feature improves depressurization simulations for stratified flow regimes, where gas sits above liquid in the pipeline. Unlike the default model (which assumes a well-mixed fluid), this functionality calculates leaked gas and liquid fractions based on:

• Leak angle (position around the pipe circumference)
• Leak diameter
• Liquid level

This allows more realistic modeling of leaks dominated by either gas or liquid, depending on their position. Directional leak is only compatible with Olga new solver (CCS) in Olga 2026.1.

Equilibrium fluid model for pumps and compressors

Olga simulator now supports a new FLUIDMODEL key for centrifugal pumps and compressors, with two options:

• IDEAL (default in Olga 2025.2 and earlier): assumes ideal gas and incompressible liquid.
• • EQUILIBRIUM: uses the specified equation of state for more accurate calculations of pump head/torque and compressor compression ratio, without idealized assumptions.

CO₂ flow model

A dedicated CO₂ flow model is now available when the solver option is set to Olga new solver (CCS) and the flow model is set to Olga. It is designed for CO₂-dominated gas–liquid two-phase flow and ensures accurate simulation for these conditions. Compared to the Olga friction factor model, the pressure drop error is reduced by 51%, the hold-up error is decreased by approximately 31%, and the accuracy of flow regime prediction is increased by 34%.

Table 1 – Improvements for the CO2 model compared to the Olga friction factor flow model

Security enhancements

As part of SLB’s Software Lifecycle Management process, SLB will conduct tests to ensure that the software is free from security vulnerabilities and malicious codes, including viruses, trapdoors, trojan horses, or ransomware that could render the software inoperable or prevent its use as documented. If SLB becomes aware of such a threat, it will use commercially reasonable efforts to provide a patch or updated version of the software to eliminate or mitigate the issue, making it available for download or installation by the customer. SLB is not responsible for viruses introduced at the customer’s site or those that did not originate from the software.

With increased focus on security from both customers and internal initiatives, three scanning tools have been introduced for Olga simulator: Mend, Spectra Assure and FlexNet from Flexera. These tools scan for vulnerabilities and enable updates or replacement of outdated libraries.

Additionally, a penetration test was conducted on Olga simulator by a third-party company, which was successfully completed from the project’s perspective.

New output variables

Two new reservoir output variables have been added:

• DPRES – Draw-down pressure
• TMRES – Reservoir temperature

These variables provide enhanced monitoring and analysis capabilities for reservoir performance.

Additional variables have been added to capture and locate the minimum and maximum inner wall surface temperature (TWS) in branches.

• MAXTWSBR – Maximum inner wall surface temperature in branch since start
• MAXTWSPOS – Distance from branch inlet where maximum inner wall surface temperature since start occurs
• MAXTWSBRCT – Maximum inner wall surface temperature in branch at current time
• MINTWSBR – Minimum inner wall surface temperature in branch since start
• MINTWSPOS – Distance from branch inlet where minimum inner wall surface temperature since start occurs
• MINTWSBRCT – Minimum inner wall surface temperature in branch at current time

Node function improvements

Several updates have been made to node functionality:

• INTERNAL node type renamed to MANIFOLD for clearer terminology.
• Sources (mass flow, pressure-driven, or tracer) can now be added to manifold, separator, and phase split nodes, with the same capabilities as sources in flowpaths.
• MASSFLOW node is obsolete and replaced by the manifold node.

Olga simulator cases created in version 2025.2 or earlier that include mass or internal nodes are automatically converted to manifold nodes when opened in the current Olga UI. Cases using manifold nodes are not backward compatible with older versions.

Steady-state preprocessor enhancements

The steady-state preprocessor (SSPP) now includes support for injection wells and negative pressure-driven sources, enabling more accurate modeling of CCS injection and drilling scenarios.

New options have been added to the steady-state preprocessor for RESREVOIRCONTACT through a new key INIWELLFLOW under BRANCH keyword. The following options are available:

• Limit the solution to production only (PRODUCTION).
• Limit the solution to injection only (INJECTION).
• No limit on the solution. The steady-state preprocessor starts with a guessed production rate (INITPRODUCTION).
• No limit on the solution. The steady-state preprocessor starts with a guessed injection rate (INITINJECTION).

Performance improvements

Computational speed in the Olga simulator has been significantly increased through enhanced parallel processing.

More Information in English:Schlumberger OLGA 2026.1.0 Testing Video