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Hydraulic Fracturing Engineering and Software Solution, for Your Most Challenging Reservoirs.

Changes – StimPlan/E-StimPlan 5.50 April 2007


  • “Geologic Models” – Added capability to save different “Geologic Models” (i.e., layer depths, stresses, modulus values, fluid loss, perforated depths, etc.) in a single STP file.
  • Automatic Tip screenout (TSO) treatment designs. The user inputs the desired propped fracture length, and the desired proppant coverage (lb/ft2) subject to a maximum net pressure rise. StimPlan then automatically generates the required pump schedule (which can then be adjusted as desired by the user).
  • Production Model – Added the ability to simulate a wellbore “skin” for horizontal well production modeling.
  • Automatic PNet History Matching. This automatically runs cases and determines the best history match.
  • Folds-of-Increase. This calculation was totally revamped to provide: a) rigorous inclusion of boundary effects, and b) the near wellbore Δp associated with frac-packs.
  • Predicted Surface Pressure – Added capability to allow different pipe friction for different sections of the wellbore when calculating the “Predicted Surface Pressure”
  • Added a “PI” plot for the Production Model output.
  • Further expanded the “Report” format output with direct, formatted output to WORD and/or EXCEL.


  • MAJOR DEVELOPMENT – Horizontal (High Angle) Well Fracturing – This significantly upgrades the ability to simulate fracturing horizontal wells including longitudinal fractures (where the fracture communicates with additional perf-orations or wellbore as it propagates) and multiple, simultaneous transverse fractures. This includes:
    > Input – Special input formats (with one example included in the figure) for entering & visualizing data for high angle wells, and
    > Output – Special 3D output for visualizing multiple fractured horizontal wells, and the relation between fractures (as seen in the figure).
  • Expanded Batch Mode Capability – The rigorous E-StimPlan Fully 3D simulations can be time consuming for some applications. This new feature allows creating a “task list” of runs. These are then executed over-night, with the results automatically archived at the completion of each simulation.
Special Input Special 3D Output

Analysis/Logs Modules

  • After Closure Analysis (ACA) – Further the “ACA for permeability” analysis to include a Type Curve Analysis for reservoir pressure. This allows reservoir pressure/permeability determination with shorter shut-in times.
  • Added log calculations for integrating density logs for OB.
  • “DConc” Variables – To analyze an actual propped fracture treatment, StimPlan historically uses a “SConc” variable (surface proppant concentration) and shifts that data to a “Downhole Concentration (DConc) variable. This is done the “Frac Job Test Analysis”. Two changes were made: > Data Plot – Surface Proppant Concentration data can be shifted to a Downhole Concentration in the Data Plot, and > External DConc Variable – The Frac Job Test Analysis can be done using an external calculated downhole concentration that has been imported.
  • Use “Other” Variables for Frac Job Test Analysis – In the analysis of a “frac Job”, the data is broken into stages for simulation. This is historically done based on pump rate/proppant concentration changes. Ability has been added to add stage changes based on other variables – maybe such as chemical concentration changes which would indicate a change in fluid rheology.
  • Log Output – Added a continuous, scaled log output to PDF files for printing a continuous log.
  • Calculate Log Stress – Added graphical input capability for reservoir pressure distribution for stress log calculations.
  • Calculated Bottomhole Pressure – Added capabilities to 1) allow different pipe friction for different sections of the wellbore and 2) specify different fluids (with different friction properties) at different times when calculating a “Calculated Bottomhole Pressure”
  • Data “ReSample” – The process where two variables are “combined” in the Data Plot, i.e., where a memory gauge Bottomhole Pressure may be combined with surface data was dramatically speeded up. This has always been a good, popular StimPlan feature, but we were seeing more and more cases of HUGE data sets, and this process sometimes took a few minutes (prompting an occasional decision to “kill” the program where users thought it was hung or something). This process ahs been dramatically improved to avoid this perceived problem.
  • Plot Coordinate Display – StimPlan has always had a user selectable option to display the cursor coordinates on any plot, but this facility has been significantly improved and speeded up.