TutorialsUsing the Hydraulic Fracture Template 1 Using the Hydraulic Fracture Template Tutorial 1: Objective The aim of the tutorial is to familiarise the user with the main features of the workflow, from model generation through running the simulation to result viewing. It demonstrates how a simulation model may be built quickly using the default values within the template. Problem description In this tutorial you build a model of a simple under-saturated oil reservoir with a vertical well. A fully-penetrating fracture is then added to the well, and then modified to be a partially penetrating fracture Getting started 1 Start ECLIPSE Office from the GeoQuest Launcher. 2 From the top menubar select File | New Project and give this project the name fracture.off. 3 Select Case | Add Case | Template. The Template Model Selection panel is displayed. 4 Set the Case Name to simple. 5 Select the Hydraulic Fracture model and OK to open the fracture template editor. The fracture template is opened with a default model pre-loaded. The template editor contains a workflow list down the left hand side. The display on the right hand side of the window depends on which option in the workflow has been selected. Model Definition The first workflow page contains general model definitions. The length of the simulation and phases should be selected here. Note The ECLIPSE blackoil simulator is run be default. If Include Turbulence and Non- Darcy Effects or Gas Condensate Reservoir is selected then the E300 simulator is run. In this case 3 phases must be entered. 6 Select the Reservoir Description workflow option. Reservoir Description Navigate through the different panels using the Next Page and Previous Page buttons. Layers In the layers page the geometry of the model is defined. Here a single 100ft layer has been added. A name for the rock type can be added, or it can be left blank to take default RESERVOIR properties. 2 Tutorials Using the Hydraulic Fracture Template Rock Properties Properties of the rock defined in the layers lanel are set here. Initial Conditions The inital pressure of the reservoir is defined. If more than one phase exists in the model, then the contact depths will alos need to be defined here. Aquifers Infinite volume aquifers may be attached to the edge of any of the layers defined. Fractures This panel allows you to add any number of fractures to the model. They may be added at any position in the reservoir (not necessarily intersecting with a well), however they must be aligned with either the X or Y axis. 7 Select the Wells workflow option This model has had one well added. The hydraulic fracture template supports an arbitrary number of wells. Wells can be added to the model using the Add Well... or Add Vertical Well... buttons from the Field tab. The coordinates of the wells are measured from the centre of the model. 8 Select W1 in the wells tree. Each well can have an arbitrary trajectory. 9 Select Production from the workflow 10 Select W1 from the Production tree. A perforation and production event has been added to the well. This is the minimum control required for the simulator to run. New events can be added by selecting the correct type from the Available Event Types drop-down and hitting New Event. 11 Select Fluid Properties from the workflow The fields that appear in this window depend on the phases in the model. For models with only oil, properties are defined here. Other fluid properties are created by correlation. The advanced user can choose to edit the keywords once they have been created, or to define them from an external file. 12 Select Simulator Controls from the workflow The controls in this window allow the user to alter the refinement in the grid. Increasing the cell size or growth rate will reduce the size of the model, and hence the simulation time. However if you want to match transient response then it is recommended that the cell sizes are not increased. Running the default model & viewing results Note that there are three buttons which are available throughout the workflow: Generate Model, Run Simulation and View Results. 13 Select Generate Model This will cause a grid to be generated honouring all the features of the model (layer boundaries, phase contacts, wells, fractures). This model is then displayed in a 3D window. Select this option at any time to regenerate the grid and see the effects of any changes in geometry you have made. Tutorials Using the Hydraulic Fracture Template 3 14 Select Run Simulation. This will cause the model to be validated and updated in the display window. The input deck for the simulator is then written. The simulator is launched in a separate DOS window. Refer to the Log Window for progress reports. Wait until Simulations finished. Timer Stopped appears in the Log Window. You are then able to look at the output of the simulator. 15 Select View Results The ECLIPSE Office Result Viewer is displayed. The output from the simulator is automatically loaded and a number of pictures are created. The display in the Result Viewer is controlled using a Graphics Run File (GRF). The location of this file is controlled by the following lines in the ECLIPSE Office config file: Note The advanced user may edit the supplied GRF or define their own in order to customise the display in the Result Viewer. For more information on the GRF file format please refer to "Graphics Run File" in the ECLIPSE Office User Guide 16 Toggle between pictures by selecting different nodes on the Pictures tree. 17 Select View | 2D. A new picture is created containing an areal view of the model. 18 Select Tools | Timestep. Select Play from Animation Controls. Individual timesteps may be displayed by selecting the appropriate time from the list above the controls. Note Please refer to "Result Viewer" in the ECLIPSE Office User Guide for more details of the features of the Result Viewer. 19 Close the Result Viewer. Adding a fracture 20 Navigate to the Reservoir Description page of the workflow window. 21 Select the Fracture page. 22 Select New. 23 Enter the following information: SECTION OFFICE SUBSECT MODULES FRACTURE-GRF d:\ecl\2004a\office\templates\fracture.grf Fracture Name f1 Half Length 200 ft Width 0.5 in Top of Fracture 6000 ft Bottom of Fracture 6100 ft Permeability 100 D Porosity 0.5 4 Tutorials Using the Hydraulic Fracture Template Hint Change the units of permeability using the drop-down to the right of the field. 24 Select Apply. 25 Run the simulation and view results as before. 26 Close the template window (this will save the current model). You will now create a case which is a clone of the current case, and modify the fracture so that it only penetrates the top half of the reservoir. 27 Select Case | Add Case | Clone from the main ECLIPSE Office window. 28 Choose a new case name and select OK. 29 Change the bottom of the fracture to 6050 feet and re-run the simulation. Note that the display now shows that the model has been divided into a number of simulation layers in order to model the bottom of the fracture. 30 Select View Results 31 Select View | 3D to display with 3D viewer with solution displays loaded. 32 Select Scene | Grid | Threshold 33 Select Initial Properties and double click on PERMX in the list. 34 Set the minimum threshold to 100,000 and click Apply. 35 The only cells displayed now are fracture cells.Zoom in and animate to see the pressure drop in the fracture.