Waterflood optimization module, tracers.
This module is used for the hydrodynamic simulation of streamlines. By means of streamlines tNavigator calculates the drainage matrix, drainage graph and drainage table, and depicts the well drainage zone. A cumulative and instantaneous drainage table provides a numerical evaluation of the interference progress between production and injection wells and the volume of crossflows between them during any time period. tNavigator fully supports tracers.
Model split: merge module.
This module provides the abilty to split large models into self sufficient fragments and merge them back together again. The model can be split using any
trajectory: a specific region of the model, or via an arbitrary user map. Distributed engineering groups can work with one common “virtual model” by using a novel “fragment catalog” concept. After running the large model one time before splitting, the boundary conditions are applied to all fragments and used in the calculations. New boundary conditions recorded in the fragments are then merged back into the large model.
The tree of model versions. Multiple-choice calculations.
The tree of model versions stores all the changes to the model in the shape of a tree in xml format and enables you to monitor all changes, alter meanings of keywords in the graphics interface and save combinations of changes as model versions. The version tree is very convenient to use when adapting the model, selecting paths of new wells, and selecting direction and length of hydraulic fractures. tNavigator enables you to submit all model versions to a queue for calculation and then view and compare calculated graphs for all versions simultaneously in one window.
For example, the trajectory of well sidetrack can be chosen with a few simple steps:
- Add the trajectory of a sidetrack with few mouse clicks
- Visually compare the different sidetrack variants efficiency
- Select multiple-choice calculations
Injection optimization module.
This mo
dule calculates the drainage matrix, drainage graph, and drainage table, which provides a numerical evaluation of the interference progress between production and injection wells and the volume of crossflows between them during any time period.
The optimization algorithm takes into consideration all the injection efficiencies and automatically adjusts the corresponding injection rates to achieve better “injection uniformity”. To keep the average reservoir pressure above the desired value, the additional “Automatic Compensation” option could be turned on.
User Arithmetic module – creation of any user maps, cuts and graphs.
tNavigator 
has unique User Arithmetic, that can be used in the graphical interface. User Arithmetic (analogous to a calculator) deals with all model parameters: phase properties, saturations, rates, injection rates, pressures, transmissibility, and historical data.
The creation of any user cuts can be done via standard math operations, keywords, and tNavigator special functions. User cuts allow the visualization of only parts of the mdoel that meet the arithmetic criteria. For example: visualize only model cells where pressure is above average pressure, or where there is only one fluid-in-place, etc.
By means of User Arithmetic any user graphs can be created, for example: total oil rate for any well group, or maximum deviation between calculated and historical values of oil rate for the wells in one fluid-in-place region, or average water saturation of blocks which contain well perforations, etc.
Uncertainty analysis module – the most effective well disposition.
This module provides the choice of the most effective FDP scenario by means of analysis and calcu-
lations of different variants. To estimate uncertainty due to a specific FDP scenario, the production and injection wells are placed randomly using Monte Carlo experiments. The placement is based on probability density functions supplied by the user (3D maps), within specified constraints (region borders, min/max distances between wells etc).
Interactive well designer: vertical and horizontal wells.
The interactiv
ity of tNavigator allows adding vertical and horizontal wells at any time step during the simulation run. This module adds a new vertical well with one mouse click on 2D or 3D maps. The trajectory of a new horizontal well is defined as a sequence of cells selected by a mouse click on the 2D map profile (user can create any 2D profile interactively during the simulation run). The new well can start working at any time step. After adding the well, we continue the run: the new well immediately starts producing!
Interactive well pattern designer.
This module provides well pattern design work for waterflood planning and optimization. With the help of an interactive pattern designer tool, any arbitrary configuratio
ns of injectors and producers can be combined in a user’s pattern. After the pattern is defined and stored, it takes only a mouse click to add the pattern at any arbitrary location(s) on the map. New wells can be added at any time step during the run. After adding the well pattern we continue the run and all new wells immediately start working! tNavigator allows the user to create an arbitrary number of different well patterns.
Fixing all grid orientation effects module.
The 
limitations imposed by the standard “two-point” approach used for numerical flux approximation are well known and require grid generators to keep the line connecting block centers and the block common faces almost perpendicular. Two-point flux approximation (TPFA) and the RFD developed hybrid (finite volume and finite element) multipoint flux appoximation (MPFA) were compared with different models with complex grids. Multipoint approximation minimizes the orientation effect MPFA and doesn’t lead to solution distortion as opposed to two-point approximation TPFA.
2D histogram module.
A unique interactive module for building and analyzing user-defined 2D
histograms and their 2D projections provides a very powerful tool for multivariate analysis of static and dynamic model parameters and their correlations before, during, and after the simulation run. This module makes it possible to build a distribution of properties in the form of a 2D histogram for all model grid cells: along X and Y axis there are arbitrary parameters chosen by user. For example, by means of 2D histogram we may visually correlate what number of blocks with high porosity have high permeability, and what number of blocks with high porosity have low permeability.
Economic parameters and reports.
This module is used for setting economic parameters and making the graph of net present value.
tNavigator creates a summary report for any time period, specified by user. The module saves the report (production report, injection wells report, reporting regions data, cumulative injection/production, etc. at every step of simulation).
Eclipse-compatible files can be created: .EGRID, .INIT, .UNSMPY, .UNRST, .SMSPEC.
Creating a new model in graphical interface: model designer and schedule loading.
The model designer allows creating a model in the graphical interface. Grid loading is supported. PVT and initial data can be loaded from text files or unloaded from other software (Petrel, RMS, etc). The loading schedule includes loading of well trajectories (las-files also supported), groups, events, and history.
Visualization isoline modul.
The distributions of any static or dynamic model properties in a 2D representation can be viewed with contour lines superimposed.
Polymer flooding based on the BrightWater® technology module
tNavigator supports polymer flooding simulation – an effective flow deflecting technology. Particles of nanopolymers increase their volume at hydrolysis or heating. These particles expand in formation pores in the direction from producers to injectors. Pores in zones of active filtration are blocked and water is forced out to the zones with low permeability via the process of activating the nanopolymer.
tNavigator takes into consideration the hydrolysis swelling rate and nanopolymer type. The simulator uses a black-oil model, where the nanopolymer is considered an admixture to the water phase that changes the filtration-capacity formation properties.
tNavigator also has an option of Surfactant injection simulation. Admixture influence to surface tension is simulated using relative phase permeability scaling.
The technology was verified on real field cases with BrightWater® injections.
Interactive tracer injection module
n tNavigator, you can mark injected water with one mouse click for each injector. The spread of the injected water will immediately be shown on the tracer map for this injector. Plots of tracer production rates will reflect the exact moment of breakthrough of the injected water into production wells.
Temperature option
This module allows the simulation of thermal effects resulting from cold water injection. One can specify the temperature of the matrix, water, oil and gas, as well as the dependence of oil and water viscosity on temperature.
tNavigator visualizes maps and graphs of temperature and fluid viscosities for model cross sections and for each grid block.
Fresh water injection into the saline reservoir module
tNavigator simulates fresh water injection into the saline reservoir.
Salt wash-out with fresh water is modeled by the following effects:
- mass of reservoir salt that can be dissolved is specified;
- spreading of injected water is calculated;
- reservoir salt is dissolved that leads to formation porosity changes and increase of salt concentration, density, and viscosity in the water;
- oil viscosity and water viscosity are equalized and this leads to improvement of oil mobility.