Specifying transient simulation input
<< Click to Display Table of Contents >> Specifying transient simulation input |
Quick start basics - Your first simulation session .
•a fuel flow change from 0.38 (max. thrust) down to 0.1 in 1 second (deceleration),
•a 5 seconds stabilisation at this fuel flow,
•a fuel flow increase to 0.38 again (an acceleration) in 1 second
•finally followed by 5 seconds stabilisation again.
1. | Click in the project tree panel on the ReferenceModel node (configuration model) to load the original configuration. Now add a new case model (name it "Transient case") and set the case type to Transient (confirm to save changes). |
2. | Enter the Fuel Control input dialog window (double-click the icon). Click the Transient tab sheet. |
Here the time-function table for fuel flow is visible. At the top row at time 0.000 the design fuel flow is already specified.
3. | Click A to add a line and enter 1 as the time value. |
When analyzing transient performance, an engine response calculation is usually started after a short period of running steady state, in this case 1 second at the design steady state operating point.
4. | Enter 0.38 in the fuel flow column Wf[kg/s] in the last row (click on it to edit). |
5. | Continue steps 3 and 4 to obtain the table shown in the figure below. Edit the time-fuel flow table using the navigation controls to go to the first line, previous line, next line or last line or to add, insert or delete a line in the table, or to delete the entire table. Note that fuel flow changes in infinite short times are invalid: a gas turbine engine control system would never be able to realize it and GSP will likely not be able to simulate it. So make sure you enter time values with reasonable (not too small) positive increments between the rows. |
6. | Optionally click Graph to view the transient input curve. |
7. | Check if transient input activated is checked and click OK (put a check mark in Active checkbox to activate the series). |