Estimation

Estimation »
In the Estimation Tree, the reaction mechanisms entered in the Chemistry Tree are reconciled with the experimental observations. In the sub-nodes of this tree, you may provide bounds on the kinetic parameters, the experimental reactor measurements, and run the estimation model in order to estimate the kinetic parameters. Grid Views Actions Grid Views Estimated Reactions Estimated LHHW Sites Estimated Reactions This grid displays the list of reactions that are included in both the Reactions and the Kinetics nodes. If you choose to estimate a reaction, the parameters of the reaction will be calculated. If you choose to not estimate the reaction, the kinetic parameters for this reaction are fixed at their initial values provided in Estimation → Parameters node. Estimated LHHW Sites This grid displays the list of all the LHHW Sites that are related with one or more included reaction, as specified in Kinetics Sites node. By default, all sites are selected as estimated. When a site is not estimated, the parameters associated with that site remain fixed during the estimation run. Note: When a LHHW Site is selected as Estimate, its parameters are estimated even if one or more reactions associated with that site are not marked for estimation. To alert the user about this issue, the last column indicates whether a LHHW site is associated with one or more reactions that have their parameters fixed because their Estimate flag is un-selected. Top of Topic Actions Initialize from Results Estimate Stoichiometric Coefficients Quick Run Open Solver Initialize from Results Initialize All You may speed up the solution of an estimation model by providing better starting points. When you have a satisfactory previous solution, you may initialize the kinetic parameters and the composition profiles with this solution. On executing this action, the values of the kinetics in Results → Parameters and the profiles in Results → Profiles are loaded into the values of the Kinetics → Reactions Parameters - Initial Estimates and Initialization Values respectively. This is the recommended option for initialization only when you already have a successful solution as a starting point. Initialize Profiles Only: This action is similar to the previous option, except that only the composition profiles are loaded from the Results → Profiles to the Initialization Values. This option for initialization is not recommended, except for special situations. Note 1 : These actions for initialization should only be performed when a previous solution is satisfactory. Otherwise, the initialization will not provide any benefit. Note 2 : The initialization values are used only when Use Provided Initial Values is chosen as the Warmstart option in the Solution Options node. Estimate Stoichiometric Coefficients By default, estimation of stoichiometric coefficients is disabled. When enabled, a new Stoichiometry tab is shown in the Estimation → Parameters node where you must define the bounds for the coefficients. Top of Topic See Also: Project Explorer Reactions Kinetics Sites Estimation → Parameters Reactor Experiments Weights Solution Options Results

In the Estimation Tree, the reaction mechanisms entered in the Chemistry Tree are reconciled with the experimental observations. In the sub-nodes of this tree, you may provide bounds on the kinetic parameters, the experimental reactor measurements, and run the estimation model in order to estimate the kinetic parameters.

Grid Views

Actions

Grid Views

Estimated Reactions

Estimated LHHW Sites

Estimated Reactions

This grid displays the list of reactions that are included in both the Reactions and the Kinetics nodes. If you choose to estimate a reaction, the parameters of the reaction will be calculated. If you choose to not estimate the reaction, the kinetic parameters for this reaction are fixed at their initial values provided in Estimation → Parameters node.

Estimated LHHW Sites

This grid displays the list of all the LHHW Sites that are related with one or more included reaction, as specified in Kinetics Sites node.
By default, all sites are selected as estimated. When a site is not estimated, the parameters associated with that site remain fixed during the estimation run.

Note:
When a LHHW Site is selected as Estimate, its parameters are estimated even if one or more reactions associated with that site are not marked for estimation. To alert the user about this issue, the last column indicates whether a LHHW site is associated with one or more reactions that have their parameters fixed because their Estimate flag is un-selected.

Top of Topic

Actions

Initialize from Results

Estimate Stoichiometric Coefficients

Quick Run

Open Solver

Initialize from Results

Initialize All

Kinetics → Reactions Parameters - Initial Estimates

Initialization Values

only

Initialize Profiles Only:

Initialization Values

Note 1 : These actions for initialization should only be performed when a previous solution is satisfactory. Otherwise, the initialization will not provide any benefit.

Note 2 : The initialization values are used only when Use Provided Initial Values is chosen as the Warmstart option in the Solution Options node.

Estimate Stoichiometric Coefficients

By default, estimation of stoichiometric coefficients is disabled. When enabled, a new Stoichiometry tab is shown in the Estimation → Parameters node where you must define the bounds for the coefficients.

Estimation »