EBSILON®Professional Online Documentation
In EBSILON®Professionalthere are two global calculation modes:
The design mode is used for the construction of new cycles. In this mode, you define appropriate specification values for all components, e.g. according to specifications from manufacturer.
When you perform a calculation in design mode, the results of the calculation are stored as reference values for the off-design calculation.
Example: In "example2.ebs", there is a steam turbine. Double-click on this component to get its specification values. The value P2N (nominal outlet pressure) is such a reference value. In design mode, it is not used for the calculation.
When you insert a new steam turbine, you get a dummy value of 0.01 bar. After a design calculation, the calculated value of the outlet pressure steam is stored in this field. You can test this by changing the value P in the "input value" component between turbine and condenser and calculating again.
In Off-Design mode, the turbine is calculated with the help of the transformation laws (in this case, the "Stodola" law), which refers to P2N. See also: Part-load - Steam Turbine
The Off-Design mode is used for a cycle already completed and calculated in design mode. Now it can be calculated for different variations (different sets of input data).
EBSILON®Professional offers the possibility of handling different cycle cases in "profiles" in a tree-like hierarchy. The root of this tree should be the design case.
To create a new profile, click on the "P" in the profile bar. The "Profiles" dialog box appears displaying the existing profile structure. To add a profile, click on "New sub-profile". You can rename the new profile by clicking two times (slowly) on its name in the tree structure.
Select the new profile in the tree structure and click on "Activate". In the profile bar combo box, the name of the current profile is displayed. You can use this combo box to switch between the profiles.
Note that a sub profile inherits all properties (e.g. the specification values and characteristics of all components) from its parent.
To switch to Off-Design mode in the current profile, activate the option window by "Extras --> Model Options" and switch to "Off-Design" in the "Global Mode" combo box. When you calculate now, the calculation will be performed according to the Off-Design rules.
If you modify the specification data, you see that values inherited from the parent profile are displayed in gray. Values that you change will be displayed in black.