Updates and bug fixes in PVTsim from 20.0 to 20.1
- Depth gradient option enhanced to ensure consistent P and Psat at Gas Oil Contact also for high vertical temperature gradients.
- For some properties incorrect derivatives returned from Flash Open Structure.
- Enhanced numerical robustness of asphaltene PT-curve option.
- Improved phase identification in asphaltene PT flash.
- Eclipse Black Oil output format changed to handle viscosities as high as 1,000,000 cP.
- Bug corrected in logic for calculating solubility of salt in H2O-MEG solutions.
- Bug corrected in logic for regression on Peneloux volume correction factors for already characterized fluids.
- C6 density erroneously corrected when match of C7+ liquid densities specified in a characterized regression.
- Inconsistent viscosity results reported by different PVTsim options for near critical fluids.
- Phase derivatives of density and entropy added to Flash Open Structure for PT non-aqueous, PT aqueous, PH and PS specifications.
- Flash Open Structure extended to also give derivatives from a PT aqueous flash when aqueous properties calculated from Water Package.
- Asphaltene Module returned incorrect Cv for single phase fluids.
- Rs vs. depth option in Eclipse Black Oil interface did not work with K-factors/Split-factors.
- Incorrect densities from Water Package for pressures in the (approximate) interval fro 750 atm to 1000 atm and temperatures below approximately 263.15 K.
- Some tie-line compositions displayed as zeros when 3 phases found at MMP.
Updates and bug fixes in PVTsim from 19.0 to 20.0
New Options/Models
- Wax Open Structure dll.
- Interface to STARS simulator from CMG.
- Import of compositional files from Eclipse Comp.
Updates and Bug Fixes
General
- Minor adjustment (+ 0.07%) of Gas Constant in cal/mol K.
- Improved numerical robustness of procedure for converting water cut to water mol%.
- Improved viscosity results for pure glycols and for water-glycol and water-methanol
mixtures.
- Temperature limit below which for viscosity of aqueous components and mixtures assumed
to be constant lowered from 243.15 K to 223.15 K.
- Help updated with info relevant for users of Office 2010.
Fluid Management
- Enhancement of options for recombining two fluids to specified saturation point.
- Bug corrected in “Clean for Mud” module. GC compositions input in weight% were handled
incorrectly.
PVT & Regression
- Characterized Regression option extended to optionally update Peneloux volume shift
parameters to comply with component liquid densities (always done with Plus Regression).
- Fix to properly catch missing saturation point in CME, CVD, DL and Viscosity experiment
simulations options.
- Plus fluid regression logic enhanced to ensure optimum density results when Peneloux
volume corrections selected as regression parameters. Cpen parameter added to output.
Flash & Unit Operations
- Logic changed to have subsequent flash specifications executed after one with aqueous
phase supersaturated with salt.
- Option added for specifying upper limit for water dew point line in phase envelope
option.
- UV Flash calculations might fail for T < 125 K due to an inappropriate lower T-limit.
Flow Assurance
- Wax temperature calculation could hang in rare cases.
- Error corrected in code for regressing to viscosity data for wax inhibited systems.
- Improved numerical robustness of asphaltene PC-SAFT option.
- Bug corrected in Hydrate module for calculation of the water-gas surface tension.
Open Structure
- Memory leak in SetCalculationError of Hydrate Open Structure dll closed.
Interface Options
Eclipse Black Oil
- Water compressibility output in PVCO and PVDO/PVDG tables erroneously calculated
at standard conditions. Corrected to be calculated at the saturation pressure at
reservoir temperature.
- Extended with combinations of PVTO/PVTDG and PVDO/PVTG.
- Enhanced procedure for correcting for non-monotony.
- Updated for handle Split-factor of 1 for all components except for one component
(which component will form a pure phase).
Vip Black Oil
- Extended with BOGTAB keyword.
- Metric Pressures in VIP Black Oil changed to be kPa instead of bar.
Prosper/Mbal
- Updated for handle Split-factor of 1 for all components except for one component
(which component will for a pure phase).
OLGA (table based)
- A new keyword STDLIQDENSITY added to OLGA two phase table for fluids containing
water. OLGA can read this from versions 6.2 and 5.3.4. Only Key format table.
- Improved numerical robustness of OLGA interface option for fluids with low concentration
of water.
- Refined phase identification check in OLGA interface.
OLGA Wax
- OLGA Wax interface extended with Wax Viscosity Correction Factors.
Weps
- Error corrected in Field Unit output.
Updates and bug fixed from PVTsim 19.0 to 19.1
- Water compressibility output in Eclipse Black Oil PVCO and PVDO/PVDG tables erroneously
calculated at standard conditions. Corrected to be calculated at the saturation
pressure at reservoir temperature.
- Error corrected in Field Unit conversion in WePs interface.
- Fix to properly catch missing saturation point in CME, CVD, DL and Viscosity experiment
simulations options.
- Wax temperature calculation could hang in rare cases.
- A new keyword STDLIQDENSITY added to OLGA two phase table for fluids containing
water. OLGA can read this from versions 6.2 and 5.3.4. Only Key format table.
- Error corrected in code for regressing to viscosity data for wax inhibited systems.
- Eclipse Black Oil interface extended with combinations of PVTO/PVTDG and PVDO/PVTG.
- OLGA Wax interface extended with Wax Viscosity Correction Factors.
- Enhancement of options for recombining two fluids to specified saturation point.
Updates and Bug fixes from PVTsim 18 to 19
New Options/Models
- PVT simulation options extended with Equilibrium Contact experiment.
Updates and Bug Fixes
General
- Tested on Windows Server 2008 and Windows 7 and installation guide updated.
- CSP viscosity model improved for P > 1000 bar.
- No longer possible to import fld-type databases (format used until version 13).
- API correlation for interfacial tension between hydrocarbon and water replaced by
Firoozabadi and Ramey (1988).
- 5 mercaptanes added to the pure component database
- Methyl-mercaptane
- Ethyl-mercaptane
- Methyl-ethyl-sulfide
- Di-Methyl -sulfide
- Di-Ethyl-sulfide
Fluid Management
- When characterizing multiple fluids to the same pseudo-components (Viscosity Tuning
and Same Pseudos options) a master fluid composition is saved in addition to the
individual fluids. The master fluid is a complete list of components contained in
all fluids in question. Dummy mole%'s of 1.E-10 are assigned to the components in
the master fluid. A master fluid is required input to Flowasta when simulating a
pipeline set-up with a source fluid containing components not present in the inlet
composition.
- The coefficients (D, E and F) in the non-Newtonian wax viscosity model saved with
the fluid and displayed under "Lumping/Corr. Fac" accessed from Current Char Fluid
menu.
- Legends with components names added to compositional QC plots.
- N2 is taken out of QC K-factor evaluation, the reason being that sample cylinders
may be contaminated by N2. Correlation coefficient (R2) requirement increased from
0.85 to 0.98.
- In QC reported Plus component mole% was not calculated correctly for compositions
in weight%, if molecular weights entered to a lower carbon number than the component
weight%'s. Plus component mole% is used in evaluation number 5 of the QC module.
- Improved check for legal plus molecular weights in Plus Fluid characterization.
- Mix option extended to handle T-dependent interaction parameters
PVT & Regression
- Option for continuous bleed off of gas in last stage of differential depletion experiment
(to better match lab experiment).
- Multiple Contact Experiment output revised to agree with format used in PVT reports.
- Depth gradient regression option enhanced to provide a better match of observed
compositional variation with depth.
- Recoveries added as primary output on separate tab in Slim Tube output.
- Default number of cells in slimtube experiment increased to 200. Default number
of time steps increased to 400. Max number of time steps increased to 20000.
- Output of key tie-line compositions under Additional Info in MMP output.
- Improved numerical robustness of MMP-algorithm.
- Saturation point option by mistake only allowed one saturation point to be calculated
at a time.
- Regression to PVT data modified to count entered critical temperature as data point.
Flash & Unit Operations
- PH, PS and VT flash specifications extended to handle pure components.
- Compressor and valve options extended to handle pure components.
Flow Assurance
- H2O-MEG and MEG-CaCl2 interaction parameters reestimated to match recent hydrate
depression data.
- By mistake simulated asphaltene onset pressures not shown after tuning to experimental
asphaltene onset pressures.
- Option for tuning asphaltene amount to experimental asphaltene onset pressure corrected
to work properly.
- Upgrade from OLGAS 4.13.1 to OLGAS 6.2.1 for use with DepoWax.
Open Structure
- PH, PS and VT flash specifications extended to handle pure components.
Interface Options
Eclipse Compositional
- Number of characters limited to 8 in output of CNAMES keyword to comply with Eclipse
input specification.
OLGA (table based)
- Standard conditions fixed to match OLGA standard.
- Standard temperature and standard pressure automatically inserted in P&T grid if
standard temperature or pressure within PT grid boundaries.
- IntelliGrid with a Grid factor of 5 is made default.
- Minimum pressure limit lowered to 0.001 bara. Limit of 0.01 bara maintained for
fluids with salts.
- Warning displayed if oil density is higher than water density. May be the case for
degassed heavy oils.
- Improved accuracy of properties of hydrate inhibitors for T < 243.15 K.
- Phase property extrapolation procedure improved for temperatures with two dew points.
- For fluids with a 3-phase area at a low temperature the IntelliGrid option might
not work properly, causing generation of an equidistant table rather than a table
with a denser grid inside the phase envelope.
OLGA Compositional Tracking
- Local tuning facilities removed from OLGA Compositional Tracking interface.
OLGA Wax
- OLGA Wax Table generation might crash or hang with SRK-Peneloux(T) or PR-Peneloux(T)
selected.
Prosper/Mbal Black Oil
- All saturation points in Prosper interface file were by mistake for standard temperature.
- The Gas Gravity written to the Prosper interface file changed to be gas from a single
stage flash or separation of the reservoir fluid to standard conditions. Previously
it was Gas Gravity of gas from single stage flash to standard conditions or separation
on the equilibrium gas at the saturation pressure at the lowest temperature in the
table.
Prosper EOS
- Composition shown with more digits in Prosper-EoS interface file.
Saphir
- Saphir interface extended. It was previously bound to always output average gas
and liquid properties. A new selection permits gas phase properties to be output
not considering a possible liquid phase.
- Error message shown if fluid at any P&T consists of 100% liquid. Was previously
interpreted as 100% gas.
WePS
- Extended to allow up to 150x150 points.
Updates and Bug fixes from PVTsim 18.0 to 18.1
Options/Models
Asphaltene
- Error corrected in option for tuning asphaltene amount to asphaltene onset pressure.
Depth gradient regression
- Changed logic to enhance match of observed compositional variation with depth.
Differential liberation
- Stage to atmospheric pressure may optionally be simulated as a continuous bleed
off of gas.
Flash
- PH, PS and VT flash specifications extended to handle pure components.
Multi Contact experiment
- Column added to output identifying saturation point as either a bubble point or
a dew point.
OLGA table interface
- Intelligrid with a Grid factor of 5 made default. This means a tighter TP-grid at
conditions with two hydrocarbon phases than at conditions with only one hydrocarbon
phase.
- Continuity problems cured in OLGA table for mixtures with two dew point temperatures.
- Robustness of table generation improved for mixtures with salts for low T and low
P.
Prosper EoS
- Composition shown with more digits in Prosper EoS interface file.
QC module
- K-factor, Hoffmann and Mass Balance Closure plots extended with legends with component
names.
- N2 taken out of K-factor evaluation in QC module as sample cylinder may be "contaminated"
by N2. After this change correlation coefficient of K-factor plot must be > 0.98
to pass QC.
Regression
- Critical temperature by mistake not counted as data point.
- Data points and compositions of zero weight by mistake added to number of data points.
Saturation point option
- Extended to allow calculation of more than one saturation point at the time.
- Enhanced numerical robustness of saturation point algorithm.
Saphir interface
- A new selection permits the user to distinguish between i) average gas and liquid
properties or ii) only gas properties.
Slimtube
- Max. number of time steps increased from 2000 to 20000.
Unit Operations
- Compressor and valve options extended to handle pure components.
General
Interfacial tension
- Correlation for interfacial tension between hydrocarbon and water modified from
API correlation to that of Firoozabadi and Ramey (1988). Only DepoWax still uses
API correlation.
Updates and Bug fixes from PVTsim 17 to 18
Options/Models
- PC-SAFT asphaltene model available to JIP sponsors as alternative to SRK/PR.
Updates and Bug Fixes
General
- Support for 64 bit Windows.
- FLEXlm license system upgraded to version 11.5 to have Open Structure applications
run from Excel under Vista.
- Improved water densities from Water Package for pressure higher than 1000 atm and
temperatures of 0-50 °C.
- New parameters for propylene glycol to give improved hydrate inhibitor predictions.
- MEG Peneloux volume shift parameter updated to give improved densities of fluid
with MEG.
- Salt CP-coefficients revised to give improved energy properties of salt water.
- Recombination failed for Plus/No Plus fluids with defined C5-C6 components other
than iC5, nC5 in case the fluids further contained an nC6 component with no density
specified.
- Improved smoothing of CSP viscosity in region between classical CSP and heavy oil
viscosity model.
- Error corrected in correlations for solubility of salts with crystal water. Solubility
of salts with no crystal water corrected to not be influenced by crystal water bound
to other salts.
- Various minor changes and updates in pure component parameters.
- Warning displayed when changing default number of pseudo-components in Unit System
& Settings.
Fluid Management
- QC module extended with check for consistent closing and opening pressures.
- Updated text message in QC module on how to "cure" a fluid composition having a
simulated separator pressure being larger than reported separator pressure.
- QC module updated to fail unrealistic GC-compositions.
- Error corrected in Same Pseudos option for Plus-fluids with only defined C7, C8
and/or C9 components. The error lead to incorrect component mole%'s.
- Weaving and Save Phase options corrected to handle asphaltene components correctly.
- Mix option corrected to properly handle mixing of fluids with components of the
same name but different properties.
PVT & Regression
- MMP algorithm enhanced (especially for CO2 injection gas). More informative error
text message in case of failure.
- Enhanced numerical robustness of option for regressing to MMP.
- Max. number of cells in Slimtube option increased to 2000. Output frequency introduced
for time steps and cell numbers.
- Enhanced numerical stability of saturation point option.
- Regression option modified to run on Vista.
- An extra datapoint was erroneously added when plotting Vrel for CME after regression.
- Bug corrected in Regression option for characterized fluids. Lumping specification
not always carried properly through to regression.
- Plus fluid regression option modified to allow viscosity model parameters as the
only tuning parameters.
- Improved numerical robustness when tuning to swelling data.
- Plus fluid regression erroneously changed the Peneloux parameter of CO2.
- Drive type (Forward or Reverse) specification not visible for set number 5 of Multi
Contact Experiment.
- Saturation point option did not work for more than 1 saturation point.
- Gas/oil mix ratio for Reverse Multi Contact Experiment changed to be per amount
of initial oil and not amount of oil at actual stage.
Flash & Unit Operations
- Improved T-dependence of H2S dissociation constant for temperatures above 70 °C.
- Numerical robustness of water phase envelope algorithm option enhanced for systems
with two hydrocarbon liquid phases.
- Energy properties and density derivates of salt water were incorrect when calculated
using Property Generator and Water Package.
- Unit Operations options by mistake returned C10+ molecular weights of zero.
Flow Assurance
- Hydrate H was not counted when making average energy properties.
- Error corrected in Hydrate Minimum Inhibitor Option. The error appeared for mixtures
with salts when more than one set of pressure-temperature values specified.
- DepoWax extended with Mukherjee&Brill pressure drop model.
- Bug corrected in DepoWax to enable simulation of pipes with identical inlet and
ambient temperatures.
- DepoWax extended to always calculate film thickness, not only in sections with wax
depositing.
- Hinner correlations updated in DepoWax to not include length dependent terms (these
are only relevant for very short pipes with significant boundary effects).
- Error corrected in DepoWax for T-derivative of the density. Marginal influence on
T-profile
- Unit for dP/dL corrected in DepoWax
- Errors corrected in DepoWax for average viscosity of oil and water and for surface
tension of gas-liquid (when water present).
- Corrected made in DepoWax in calculation of heat transfer using Petukov-ESDU correlation.
- Error corrected in DepoWax causing same simulation results after all time steps.
- Error in thickness of laminar film corrected in DepoWax. Caused too much wax deposition.
- Time step control implemented in DepoWax causing wax build-up to be almost independent
of time step length.
- Default Hinner correlation in DepoWax changed from Petukov-ESDU to Sieder-Tate,
as the former is discontinuous in Reynold's number.
- PC-SAFT available as asphaltene model for JIP sponsors as alternative to SRK/PR.
Open Structure
- Open Structure Flash extended with option for calculating water properties from
water package.
- Error corrected in Open Structure Flash in option for specifying phase type of single-phase
fluid.
- PS-flash could not be run in Open Structure Flash.
- In the Open Structure Fluid Utility schema validation made more liberal to allow
reading XML-fluids of other versions than the current one. This ensures better version
compatibility of UniSim cases setup using the Calsep PVTsim Engine.
- Open Structure DataLayer now distinguishes between a database open by another user
and a file, which has a not recognizable database format.
Interface Options
Eclipse Black Oil
- Eclipse Black Oil interface updated with option to enforce monotony in properties.
- Eclipse Black Oil interface updated to give Rs versus depth values consistent with
Rs in the PVTO table also when separator train specified.
- Bug corrected in Eclipse Black Oil table for keyword PVTG. The bug sometimes caused
lack of gas properties at pressures above dew-point pressure.
Hysys
- Component densities transferred to Hysys changed from being input densities to be
densities calculated using Peneloux volume corrected EoS.
OLGA
- Error values now always bolded in the Olga.
- IntelliGrid option in Olga interface updated to work correctly for fluids containing
aqueous components.
- Writing of lines with PBUBO and PDEWO and corresponding temperatures fixed not to
end with "," if the values following the "," are less than 0. The "," causes problems
for the Olga plotting tool when reading the lines.
- Numerical robustness of OLGA interface improved.
OLGA Wax
- Improved numerical robustness of OLGA Wax Table generation.
- Component names were missing in the OLGA Wax table for components with no blanks
among first 10 characters of the component name.
- Incorrect cloud point temperatures in OLGA Wax table if Number of P-points > Number
of T-points.
- Table generation failed fluids containing pseudo-components with zero wax contact.
Prosper/Mbal Black Oil
- For temperatures with two saturation pressures the saturation pressure written to
the Prosper/Mbal interface table was the lower one. Changed to be the higher one.
Updates and Bug fixes from PVTsim 17.2 to 17.3
- Error corrected in saturation point logic that might cause failure of regression
when including swelling data.
- Limit on number of cells in slimtube option increased to 2000. Time step and cell
output frequency introduced.
- Tabulated saturation pressure in Prosper/Mbal interface changed to always be the
higher one (relevant for temperature tabulation points with two saturation point
pressures).
- Plus regression erroneously changed the Peneloux parameter of CO2 marginally. This
caused problems e.g. in MMP simulations with a CO2 "No Plus" fluid as injection
gas.
- Error corrected in DepoWax causing the simulation results to be the same after all
time steps.
- The Save Phase option erroneously assigned asphaltene components an asphaltene fraction
of 0.0. Corrected to be 1.0.
- Error corrected in weaving option for asphaltene components.
- Too low a thickness of laminar film layer in DepoWax caused too much wax deposition
Updates and Bug Fixes in PVTsim from 17.1 to 17.2
- Numerical robustness of MMP algorithm improved for CO2 as injection gas. More informative
error message in case of failure.
- Bug corrected in Eclipse Black Oil table generation for keyword PVTG. Bug seen for
undersaturated properties tabulated at input pressure stages and "const comp extrapol".
No gas properties generated for P > dewpoint pressure.
- Component names missing in OLGA Wax table for components with no blanks among first
10 characters of component name.
- Bug corrected in Same Pseudos option causing incorrect component mole%'s for Plus-fluids
with only defined C7, C8 and/or C9 components.
- Unrealistic GC-compositions might cause crash in QC mud-contamination check.
- Check implemented for license file location in Registry on Vista.
- Bug corrected in DepoWax for surface tension of gas-liquid, when water present.
- Correction in calculation of heat transfer in DepoWax for Petukov-ESDU correlation.
- Incorrect cloud point temperatures in OLGA Wax table if Number of P-points > Number
of T-points.
Updates and Bug Fixes in PVTsim from 17.0 to 17.1
- Component densities transferred via Hysys interface changed from input densities
to be densities calculated with Peneloux corrected EoS.
- Hydrate code corrected to also account for Hydrate H in average energy properties.
- Saturation point option changed to work for more than 1 saturation point at the
time.
- Intelligrid option in OLGA interface changed to work correctly also for fluids containing
aqueous components.
- Numerical robustness of OLGA saturation point algorithm improved for narrow boiling
mixtures.
- Section length term 'turned off' in correlations used to calculate Hinner as the
term is only relevant for very short pipes.
- Changed Schema validation in Open Structure modules to keep consistency UniSim design.
- Error corrected in lumping. It appeared when regressing on already characterized
fluids and regression option accessed from component input menu.
- Enhanced smoothing of CSP viscosity in region between classical CSP and heavy oil
viscosity model.
- Water properties from water package available as an option in Flash Open Structure.
- Error corrected in Property Generator for density derivatives of salt water.
- Warning about unavailable database changed to distinguish between "database open
by other user" and "database format not recognized".
- FLEXlm software license system updated to version 11.5 to have Open Structure applications
run from Excel under Vista.
- Error corrected in correlations for solubility of salts with crystal water.
- Inaccurate minimum inhibitor requirements in Hydrate module if more than one P&T
set specified and water phase contains salt.
- Improved accuracy water densities from water package for pressures > 1000 bar/14700
psia.
