Manage SUTRA Boundary Observations Dialog Box

  • Scroll to top of this topic Scroll to Top of Page

  • Print the current topic Print Topic

  • No expanding elements on this page Show/Hide Expanders

The Manage Sutra Boundary Observations dialog box is used for defining observations related to flow through SUTRA boundary conditions for use with PEST. It is displayed by selecting Model|Manage SUTRA Boundary Observations...

The left side of the dialog box has a tree control with a list of boundary observation types that can be used for calibration observations. If any calibration observations for these boundary types have been defined, they will be child nodes from these root nodes. You can add a boundary observation item by selecting one of the root nodes and clicking the Add button in the lower left part of the dialog box. You can delete a boundary observation item by selecting it and clicking the Delete button next to the Add button.

When a observation item is selected in the tree control, the main part of the dialog box can be used to edit its properties.

Observation series identifier is a unique name used to distinguish a group of observations that all include the same objects.

Each observation series can define one or more calibration observations. It can also define comparison observatinss between the calibration observations it defines. Each Observation series must also include one of more objects that define the appropriate boundary type for the observation. These are specified on the Objects tab.

Beneath the Observation series identifier is a tab control with two tabs.

The Observation times and values tab is used to define the observation properties whereas the Objects tab is used to define which objects are part of the observation.

There are two types of observations that can be defined for an observation item: Direct observations and Comparison observations. Direct observations are measures of flow through a boundary whereas with Comparison observations, the observation value is the difference between two direct observation values.

Direct Observations

Observation Name (OBSNME) is the name of the direct or comparison observation.

Observation type is the type of data to be extracted from the SUTRA output file for direct observations. For example, with specified pressure boundaries, there are three types of data that could be used for direct observations: the flow rate through the boundary, the concentration or temperature of the flow through the boundary, or the resultant mass or energy flux through the boundary.

Observation Group (OBGNME} is the name of the observation group to which the observation is assigned. Observation group names are specified in the Pest Properties dialog box. Observation group names can be be assigned later in the Pest Properties dialog box if a suitable observation group has not yet been defined.

Observation Time is the time at which the observation was made.

Observation Value (OBSVAL) is the measured value to which the simulated value should be compared.

Observation Weight (WEIGHT) is the weight assigned to the observation.

Comment is an optional comment about the observation.

Comparison Observations

Observation Name (OBSNME) is the name of the comparison observation.

Observation Group (OBGNME) is the name of the PEST observation group to which the observation is assigned. Observation group names are specified in the Pest Properties dialog box. Observation group names can be be assigned later in the Pest Properties dialog box if a suitable observation group has not yet been defined.

First Observation (OBSNME1) is the name of the first observation that will be compared.

Second Observation (OBSNME2) is the name of the second observation that will be compared.

Observation Value (OBSVAL) (OBSVAL1 - OBSVAL2) is the observed difference in value between the first and second observations. It is computed as value of the first observation minus the value of the second observation.

Observation Weight (WEIGHT) is the weight assigned to the comparison observation.

Comment is an optional comment about the observation.

Objects Tab

The Objects tab contains two list of objects labeled Available objects and Used objects.

The Used objects are objects that define boundaries of the appropriate type that are used when determining the simulated values. The Available objects are other that define boundaries of the appropriate type but that are not used when determining the simulated values. Buttons between the two lists can be used to move selected objects between the lists. Objects can also be added or removed from an observation group on the SUTRA Boundary Observations panes of the Object Properties dialog box.

Each used object has a Factor associated with it. Factor is a formula that should evaluate to a value between 0 and 1 inclusive. By default Factor is set to 1. Factor can be used to excluded some of the flow through the nodes defined by an object from an observation. For example, if flow through only half of the boundary nodes defined by the object should be part of the observation, Factor can be defined so that it evaluates to 1 for the nodes that should be included and to 0 for the nodes that should be excluded.