Release Notes
Current Release 3.014 – November 04, 2025
• Revised help menu and activation panels to open help files on both Whitson and Nationsconsulting web sites. Activation panel now sends activation code requests to sales@whitson.com. • Added preference to open a standard baseline dataset instead of the last file used. Fixes several other nuisance bugs identified by Oxy Gas Lift specialists. • Stress tested GL mandrel placement code to determine the impact of implementing the newest API RP on mandrel placement. Also confirmed that cases using the dual Gas gradient do not automatically space correctly. designes sing this method have to be manually adjusted below the gradient change, especially if the slope cange is significant. • Confirmed preference to "keep Legend in upper right corner" was not being retained or implemented correctly so re-coded that.
Release 3.000 – April 13, 2025
SNAP has some source code that can be traced back to FORTRAN IV hydraulics routines written in the 1970s, while other components were written last week. Keeping software up to date involves adapting to evolving technologies, new operating systems, shifting language trends, and changing Integrated Development Environments (IDEs).
Those on the bleeding edge rarely deliver a final product – while those maintaining legacy products rarely adapt to the ever-changing bleeding edge.
For the first time in many years, SNAP is achieving both.
- Math libraries for Hydraulics, IPR, Gas Lift, Jet Pumps, and curve fitting have been successfully ported from Visual Studio 2010 to VS2022 (the latest).
- Executable program workflows, I/O routines, and grid control libraries were also migrated to VS2022.
- Graphics libraries, implemented as ActiveX controls, remain compatible with new code and continue to function without requiring recompilation.
We have thoroughly stress tested version 3.000 while tackling several significant problems that showed up during the update. Some of these were old problems that VS2010 didn't know/care about, while others are new bugs created by the more stringent rules of 64-bit architecture and Platform Toolset 143.
Please contact us if you see anything that needs our attention since significant change brings significant risk.
A sincere thank you to those who encouraged us to update to VS2022 – especially Steve Harmon, Pryanka Tayade, and Sandy Williams. I tend to stick with what works but your persistence made this progress unavoidable.
Release 2.971a – April 13, 2025
- For new datasets with no deviation data, the deviation survey panel will show as the top tab of the wellbore collection of tabs...
Release 2.970 – March 30, 2025
- For simple gaslift cases, added new calculation to report predicted lift depth on reports and graph headers...
Release 2.967 – February 26, 2025
- When the Detailed Temperature Options panel is opened over one of the 3 different GasLift panels...
Release 2.966 – January 22, 2025
- Stress tested process to empirically define low-rate jet pump solutions...
Release 2.965 – November 13, 2024
- Stress tested process to empirically define low-rate jet pump solutions...
Release 2.962 – October 31, 2024
- Added new well selection options for US and Norway Conocophillips users...
Release 2.957 – September 16, 2024
- Added method to implement arbitrary pressure reduction moving uphole at any GL valve...
Release 2.956 – August 25, 2024
- Added improved data handling on Jet Pump panel...
Release 2.955 – August 15, 2024
- Added new minimum lift method...
Release 2.952 – July 25, 2024
- Added new plotting option to show superficial gas velocities instead of actual...
Release 2.949 – June 12, 2024
- Moved this release notes section to the top of the help file...
Release 2.946 – May 22, 2024
- Rebuilt sensitivity intersection results portion of text reports...
Release 2.945 – May 14, 2024
- Added special case where an orifice is run in the Top station...
Release 2.942 – April 16, 2024
- Fixed bug (since version 2.938) where velocity values...
Release 2.941 – April 3, 2024
- Significant changes as noted below...
Release 2.937 – February 29, 2024
- Significant changes as noted below...
Release 2.820 – September 30, 2021
- Significant changes as noted below...
Release 2.703 – December 4, 2019
- Added Deviation survey entry and usage...
Release 2.701 – November 19, 2019
- Revised all grids to allow cell height adjustments...
Release 2.700 – November 11, 2019
- All panels can be made Modeless...
Release 2.463.497 – December 20, 2015
- Simplified and stabilized Gas Lift Temperature options...
Release 2.448.497 – September 9, 2015
- SNAP now can be run without formally installing it...
Release 2.445.497 – August 14, 2015
- A huge number of small and large enhancements...
Release 2.346.497 – June 30, 2013
- Improved Gas Lift Troubleshooting algorithms...
Release 2.343.497 – May 24, 2013
- Revised Excel Hydraulics Example...
Release 2.331.497 – November 24, 2012
- Updated VPC parameters to 2012 values.
Release 2.326.497 – October 3, 2012
- Improved stability of the simple gas lift panel...
Release 2.315.497 – July 25, 2012
- Tuned up labeling on headers...
Release 2.313.497 – July 10, 2012
- Removed call to get the Network ID code...
Release 2.306.497 – June 7, 2012
- Implemented several enhancements to multi-zone IPR visualization...
Release 2.295.497 – March 15, 2012
- Continued to fine tune and upgrade Gas Lift features...
Release 2.273.497 – November 20, 2011
- Incorporated first complete PPO valve and XOM Mandrel design options...
Release 2.256.497 – June 29, 2011
- Enhanced the Mandrel design options...
Release 2.255.497 – June 2, 2011
- Added a few more data elements...
Release 2.252.497 – May 17, 2011
- Added additional detail on Gas Lift Mandrel design...
Release 2.248.497 – April 18, 2011
- Remove context specific help toolbar button...
Release 2.243.497 – March 16, 2011
- Solidified mandrel spacing code...
Release 2.241.497 – March 12, 2011
- Re-arranged detailed gas lift dialog...
Release 2.231.497 – January 1, 2011
- Made switching between loading rate vs. pressure plot...
Release 2.229.497 – December 19, 2010
- Revised the algorithm for simulating gas lift kick-off formation...
Release 2.227.497 – December 8, 2010
- Pushed the 2011 password to the installers...
Release 2.216.497 – October 8, 2010
- Fixed a few special case graphics issues...
Release 2.212.497 – September 26, 2010
- Fully tested beta release of Batch Gas Lift troubleshooting utility...
Release 2.204.497 – August 25, 2010
- Tied ConocoPhillips Batch Gas Lift troubleshooting utility...
Release 2.200.497 – August 6, 2010
- Rebuilt and solidified gas lift features...
Release 2.169.497 – March 5, 2010
- Locked in dialog locations after pressing the OK...
Release 2.166.497 – February 14, 2010
- Recoded the force balance routines...
Release 2.163.497 – February 10, 2010
- Enabled a soft return when reaching the right edge of a grid...
Release 2.160.497 – February 2, 2010
- Added code to accept the enter key...
Release 2.158.497 – January 15, 2010
- Added flowline specific pipe sizes...
Release 2.155.497 – January 6, 2010
- Re-wrote check-box logic...
Release 2.151.497 – December 1, 2009
- Fixed an interface bug where IPR layers greater than 2...
Release 2.151.497 – November 30, 2009
- Increased file size that can be saved and retrieved...
Release 2.149.497 – November 23, 2009
Added option to include "loading area shading" to gas well models. Option included in global preferences and a toolbar button. Testing indicates that refreshing is adequate but plots move back to the last closed position when swapping back and forth. Shaded areas do not yet automatically grow with an increase in scale, but will re-fill with a new calculate. Checked and repaired a temporary (has been in place for perhaps 6 months) conversion error in the minimum lifting rate routine.
Release 2.148.497 – November 19, 2009
Added more flexible jet pump modeling features. Removed "Move objects on the graph" toolbar button since it was an unnecessary interface obstacle; all prior functionality still exists but you no longer have to press the button first. Tested minimum lifting area shading logic.
Release 2.143.497 – October 20, 2009
Activated alpha testing module on Plunger lift options showing loaded and unloaded hydraulics plots. Transient codes for build-up and drawdown were imported and compiled but are not yet tied into the GUI.
Release 2.137.497 – September 20, 2009
Rebuilt zonal summing routines for both types of injectors and both types of producers. Removed secondary phase calculations until the last step which simplified and sped up the code significantly. Tested against 4 test suite datasets that use multiple layers. Note: Modified IPR liquid viscosity weighted average from harmonic to a resistance model at 25% saturations of the primary phase. This change may affect results reported from older datasets so may be moved to a preference item in a future release so the old method can remain available.
Release 2.132.497 – September 14, 2009
Retested and stabilized functionality for pulling recent well tests from ConocoPhillips Oracle databases. Added check box to preferences panel for to allow legend to stay where placed instead of always moving back to upper right hand corner. Added the Haaland equation direct solution for friction factors (thanks Drew).
Release 2.128.497 – August 20, 2009
Several working releases of the C7 implementation are circulating. Tested with 10 students for a 5 day class with no problems. Repairs downward compatibility issue on non-VPC gas-lift designs for Prudhoe Bay users.
New features in this version include the Shui-Beggs Temperature prediction for flowing gas lift designs, improved multi-layer injection predictions, improved GOR handling in multi-layer crossflow cases, and several maintenance fixes and upgrades. Still supplying the C6 version but this version will soon be able to replace it w/o regrets.
Release 2.120.497 – May 27, 2009
Improved handling of singularity in Gray correlation friction calculation at load-up conditions resulting in a smoother curve below the load-up point. Preparing for first beta release of Visual C7.1 version in June.
Release 2.119.497 – May 21, 2009
Several significant upgrades including new velocity gradient plots. Improved the tutorial in this help file. Fixed a calculation error that incorrectly straightened base IPR curves in cases using Vogel with reservoir data including completion parameters that were not restrictive (should have been be irrelevant). Reviewed all other completion methods for similar problems with none found.
Release 2.114.497 – April 8, 2009
Added wellbore correlation from Rajan N Chokshi, University of Tulsa revised Aug 1994. Wellbore segment arrays increased from 50 to 100 items in hydrlc32.dll.
Release 2.112.497 – March 16, 2009
Redirected Conoco Phillips Oracle database connections to the new Oracle 10 instance, OAKATDT1.
Added Annular+Tubing flow option to evaluate flow from both a tubing string and an annular space. Tested cases with and without a zero size lower tubing string to evaluate cases with a tubing tail set high. Repaired zone naming logic so that defaults are now "none" instead of "-1.00000".
Release 2.111.497 – March 13, 2009
Posted a release detailed hydraulics report page for the entire wellbore under the operating condition that considers isolated inflows from each layer (page forward to the last page). See release 2.109 discussion. Added Critendon method of determining Annular flow effective diameter instead of wetted radius method.
Release 2.109.497 – March 3, 2009
Posted a beta release detailed hydraulics report page for the entire wellbore under the operating condition that considers isolated inflows from each layer. This report page will follow all other detail page reports. The intent is to see the change in flow regime within the completion section and Identify at which zone standing water will load the lower layers and match the tubing gradient plot under similar conditions. Clarified some text on the gas lift report notes.
Release 2.107.497 – February 17, 2009
Added rate and sensitivity count to top of detailed Hydraulics report pages. Improved units text-box spacing on water and Gas injectivity index panels. Still need to improve final Gas injectivity index units features.
Release 2.106.497 – January 16, 2009
Increased size of working arrays that caused a gradient calculation failure for gas lift cases with more than 20 wellbore segments . Improved column labels on gas-well gas lift reports.
Release 2.105.497 – January 6, 2009
Reset GL Orifice gas passage methods to not include the incremental pressure drop used for bellows Valves. Enables moving of legend on Gas Lift plots, added clarification text on Psc Bot Bel legend item on gas lift design plot.
Release 2.104.497 – January 6, 2009
Added and tightened up several gas lift issues related to Valve Performance Clearinghouse codes. Re-set the correct Y axis labels on gradient plots. Bug exists between versions 99-103.
Release 2.091.497 – November 25, 2008
Fixed numerical interpolation routines to more accurately determine intersection points. Versions starting in early 2008 were inadvertently using a stair-step interpolation as opposed to a linear interpolation, which was fallout from efforts to eliminate divide-by-zero occurrences. This change will only affect reports and sensitivity plots.
Release 2.089.497 – November 23, 2008
First beta release incorporating Cliff Redus' restriction code re-write. Older files may show different results starting with this version if they include small restrictions.
Release 2.087.497 – November 14, 2008
Identified problem with working files being written to the system defined "working directory." These are now stored in the application directory. Work in progress on improved choke code and gas lift enhancements.
Release 2.083.497 – October 23, 2008
Forced entered WHP into the appropriate segment in cases with flowlines and simplistic temperature definitions. Switched back to cumulative length based interpolations on sub-segment temperature profiles. Version releases between 10/1/2008 and 10/23/2008 had a TVD based interpolation to more closely mimic geothermal gradients. As always, rigorous temperature calculations are an option for those who do not know their temperature profiles through measurements. +Minor interface refinements.
Release 2.079.497 – October 15, 2008
Formalized VPC casing pressure adder so that :
1) value is saved with the dataset,
2) is used in all VPC calcs, and
3) retains persistence when tabbing between Gas lift Dialogs
Major Release History
SNAP 1.017 Beta Release (Original Release Date: 3/19/98)
SNAP is the System Nodal Analysis Program developed by Engineers and Programmers working for ARCO E&P Technology using code dating back to the early 1980's. The System Nodal Analysis Program analyzes the intersection of Inflow Performance Relationship (IPR) curves and Tubing Hydraulics curves to predict flow rates. It does not require any external databases or data files and can be run in the same manner as any other Windows Application.
More Recent Releases
After 497 incremental program enhancements to version 1.000, the version number was incremented to 2.000 in 2007 to signify the significant addition of SI and other Units, HTML Help, and the first release of Gas Lifting features for gas wells, as well as VPC gas passage relationships for gas lift valves.
This is a help document outlining the options available with the SNAP application. It is our hope that the following information will help clear up questions on the definitions of the variables found in the application.
We appreciate any advice you may have as to how to better express the terms defined within the program.