Using Automatic Parameter Estimation (Hybrid Model)
Click to see Subtopics:Automatic parameter estimation (APE) is used to perform history matching. The steps to do this are: specify the data points to be used, specify the parameters to vary, and run APE.
Specify Data Points to be Used by APE
By default, all data points are selected to be used by APE. If your data has some outliers, or some periods of unreliable data, you can deselect these points.
1. Click the Display a toolbar with options to select data points icon on the Plots tab, and select the appropriate sub-option to remove unwanted data.
2. If the well has a typecurve or unconventional reservoir model (URM) analysis worksheet with some of the data points selected, you can copy the data selection from the typecurve to the model by clicking the Copy Data Selection from Typecurves icon (
). Deselected data points are displayed in gray.
3. If it is important to match some specific portion of the data (e.g., the last part of the production), you can weight data points by clicking the Weight Data Points icon (
). Weighted data points are displayed in a brighter color.
Specify Parameters to Vary
To specify which parameters to vary:
1. To select which parameters to vary, click the Automatically calculate variable checkbox to the right of the parameter's field.
2. To vary a certain parameter within given limits, click the View Defaults and Limits button to the right of the field.
3. Enter the appropriate values, and then click the Accept button.
Run Automatic Parameter Estimation
To run automatic parameter estimation (APE), click the APE icon (
).
While APE is running, selected parameters are automatically varied to minimize the error between the simulated pressure and the actual pressure. The updated simulated pressure is shown on the plots while the calculation is running.
While APE is running, you can wait until it finishes, or if the history match looks good, you can stop the process by clicking the APE icon ().
After you have achieved your desired result in Use Rate Calculation mode, we recommend that you switch to Use Pressure Calculation mode, and verify if the calculated rate matches the actual rate. If these rates are not close, additional history matching should be done.