Cycle Design Parametric Study GasTurb 12 – Tutorial 2 Cycle Design Parametric Study Copyright © Joachim Kurzke
For this tutorial we will consider a 2 Spool Turbofan. GasTurb 12 Main Window For this tutorial we will consider a 2 Spool Turbofan. Copyright © Joachim Kurzke
We Need Some Data Copyright © Joachim Kurzke
First we run a single cycle Input Data Page First we run a single cycle Copyright © Joachim Kurzke
Single Cycle Output Copyright © Joachim Kurzke This is a cycle for a business jet engine. Cruise flight condition is 11000m @ Mach 0.8. The overall pressure ratio is rather low (P3/P2=17.33), burner exit temperature is 1450K and the bypass ratio is 6.
Turbofan Station Designation Copyright © Joachim Kurzke These are the locations of the thermodynamic stations and the secondary air system paths
Now we go for a Parametric study. Copyright © Joachim Kurzke Now we go for a Parametric study.
Parameter Selection Copyright © Joachim Kurzke Click here to run all cases This is the HP Compressor Pressure Ratio of the Single Cycle calculated before this parametric study. Choose a property from the list, double click or drag it to the parameter page on the right. You can also click the arrow for moving a parameter from left to right. We employ HP Compressor Pressure Ratio as the only parameter for now. Copyright © Joachim Kurzke
Graphical Output Picture Definition The result of a parametric study is presented graphically. Sp. Fuel Consumption and Net Thrust are the default plot parameters. To employ Overall Pressure Ratio P3/P2 as x-axis, drag it to the box below the schematic picture. Then click Draw y=f(x) Copyright © Joachim Kurzke
Single Parameter Plot With a Single Y-Axis This black square marks the Cycle calculated before beginning the Parametric study Copyright © Joachim Kurzke We go back to the previous window and select a new view (New Picture) of the data created in the Parametric Study
Single Parameter A Plot With Several Y-Axes Select the number of y-axes first! Copyright © Joachim Kurzke We will employ several y-axes Drag four parameters to the respective y-axis boxes. Then click Draw y=f(x)
Plot With Four Y-Axes Copyright © Joachim Kurzke On each y-axis there is a different symbol. This line belongs to the LPT Pressure Ratio axis – the symbols on the line and on the axis are the same. Close this window to go for a new Parametric study. Copyright © Joachim Kurzke
Parameter Selection Adding a Second Parameter Click this tab for specifying the second parameter Use these numbers Click here to run all cases This is the Burner Exit Temperature of the cycle calculated before this Parametric study. Copyright © Joachim Kurzke We employ Burner Exit Temperature as the second parameter
The Default Plot No Contour Lines This little black square marks the cycle calculated before beginning the Parametric study Next have a look at all the data from a specific parameter combination. Click Detailed Output Copyright © Joachim Kurzke
Getting the Detailed Output for any Parameter Combination Now we will add more information to the picture. Click New Picture Copyright © Joachim Kurzke SELECT Double click (in GasTurb) to select T4=1425 and HPC Pressure Ratio = 9
Contour Parameter Selection An option: Click to sort the property names alphabetically Copyright © Joachim Kurzke
Plot with Contours Copyright © Joachim Kurzke
Click to apply the new settings Editing Contours Edit the numbers: Lowest Contour Value = 0.435 Step Size = 0.005 Click to apply the new settings Copyright © Joachim Kurzke
Let us add now a design limit for T45 of 1200 K The Customized Plot Let us add now a design limit for T45 of 1200 K to the carpet. Copyright © Joachim Kurzke
Showing Design Limits Example: Add a Boundary for T45>1200K Copyright © Joachim Kurzke Upper or lower limit
Showing Design Limits Copyright © Joachim Kurzke Next we go for another New Picture Copyright © Joachim Kurzke
Specific Fuel Consumption (SFC) as a Function of HPT Pressure Ratio The disadvantage of this plot is that there is no information about HPT Pressure Ratio anymore. To correct for that we add contour lines for HPT Pressure Ratio. We go for another New Picture Sometimes the lines are overlapping and the plot is difficult to read Changing the Layout resolves this problem Copyright © Joachim Kurzke
Closing this window brings us back to the cycle design input window Specific Fuel Consumption (SFC) as a Function of Ideal Jet Velocity Ratio V18/V8 For each HP Compressor Pressure Ratio the best SFC is achieved if the Ideal Jet Velocity Ratio V18/V8 is approximately 0.8. This relation between the bypass nozzle velocity V18 and the core nozzle velocity V8 can be achieved by choosing the right Outer Fan Pressure Ratio. In the next parametric study we will iterate Outer Fan Pressure Ratio in such a way that the Ideal Jet Velocity Ratio V18/V8 is equal to 0.8. Thus all the cycles are optimized for Specific Fuel Consumption SFC . Copyright © Joachim Kurzke Closing this window brings us back to the cycle design input window
Go for Iterations Copyright © Joachim Kurzke
How to define an iteration is shown in the Define the Iteration How to define an iteration is shown in the Single Cycle Tutorial Copyright © Joachim Kurzke
Re-Run the Parametric Study Copyright © Joachim Kurzke
No Change in this Window Copyright © Joachim Kurzke
Outer Fan Pressure Ratio is Optimized Copyright © Joachim Kurzke
GasTurb Copy to Clipboard, Pasted into Power Point and Re-Sized Copyright © Joachim Kurzke
De-Activating the Iteration Click to de-activate the iteration Now run the Parametric study again Copyright © Joachim Kurzke
Outer Fan Pressure Ratio = 1.8 Iteration is De-Activated Adjust the scales to make the picture comparable to the picture with the optimized Outer Fan Pressure Ratio. Copyright © Joachim Kurzke
Outer Fan Pressure Ratio = 1.8 Repeat clicking this button until no parameter values are shown Copyright © Joachim Kurzke
Outer Fan Pressure Ratio = 1.8 Select a color Copyright © Joachim Kurzke
The Overlay on the Clipboard Copyright © Joachim Kurzke
Pasted on the Other Picture This slide ends the Cycle Design Parametric Tutorial Copyright © Joachim Kurzke