How to Enable/Disable Restart

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Why should you Enable or Disable the Calculation Restart Feature?

The Calculation Restart feature was added to the OLI Solver to help speed up calculations. In the OLI solver an array of equations are created to solve the chemical equilibrium and mass/heat balances for the simulation. This array of equations need to have an initial value created for the unknown variables. The program that does this in the OLI software is called the "Initializer". The initializer program can be quite slow in making the guess for the initial values. In multiple point calculations such as a survey, if the preceding point converged we can use its values to set the initial value for the next point. This is especially useful if the next point is not too different from the preceding point. This can speed up a calculation.

For the Aqueous Thermodynamic Framework (AQ) the default setting is to enable the restart function. OLI has over 40 years of experience with the AQ framework and our initializer is quite well established. For the Mixed-Solvent Electrolyte Thermodynamic Framework (MSE) the default setting is to disable the restart function. Since water (H2O) is not required to be present, the next point in a survey may be quite different from the preceding point. Thus restarting the initial values may be unreliable.

Sometimes you will want to switch on or off this setting. This is how to do it.


Using the Tree-View method to toggle the restart feature

Locate your survey from the tree-view on the left:

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Right-click the survey:

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Select Calculation Options:

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Click on the Convergence Tab:

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Check or uncheck the restart option as required. Click the OK to update the file and then run (or re-run) your calculation. You may see small changes from any previous runs.


Using the Specs... button method to toggle the restart feature

From the calculation definition click the Specs... button.

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Click on the Convergence Tab:

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Check or uncheck the restart option as required.

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Click the OK to update the file and then run (or re-run) your calculation. You may see small changes from any previous runs.


--Jberthold