Tutorial 1

Working with a saved model. Load an existing geometry model. Change some geometrical parameters. Generate the lattice to review the model and save the new configuration.


  Start Tornado
Go to the geometry setup menu
Select load geometry
From the list of files, select A320W

 >...
>Load file:                         A320W

From the main menu, generate the lattice with option 0 (Freestream-following wake). This will give you an error message telling you that no state is loaded. However, you can now plot the geometry from the post processing menu. Do so and have a look at figure 1. In this figure you can see that the reference point is positioned at the main wing apex, perhaps not the best position.

To change it, select option 4 in the main menu to get to the move reference point position function:

 """"""""""""""""""""""""""""""""""""""""""""""""""""""
"                                                   
"  Main Menu                                        
"      |----->Move reference point                  
"                                                   
""""""""""""""""""""""""""""""""""""""""""""""""""""""
 
    [1]. Move reference point in x
    [2]. Move reference point in y
    [3]. Move reference point in z
 
    [4]. Move reference point to position on MAC
 
    [0]. Cancel

>Please enter choice from above:            4



Select option number 4, and then:

 >Move reference point to percent of MAC  [ % ]:    25

When this is done, regenerate the lattice.

After changes to the geometry or state, always regenerate the lattice

Plot the geometry from the postprocessor to verify that the reference point has moved.
(You need to close the earlier plot to prevent the new one to be superimposed.)

Enter a state with 5 degs alpha, 0 beta and 0 [P Q R] at sea level and 10 m/s velocity.

Regenerate the lattice and go to the processor access and perform a simple solution.

Give this computation the jid test2. Review the results.

From the main menu, select the option change rudder setting. You'll be asked which rudder to set. Trailing edge control effectors (CE) are numbered wing wise and span wise (in the same order as they where defined). In the current design, the first CE is the traditional inboard flap, located on partition number 2, the second is the outboard flap on the third partition. The third is the aileron located on partition number 4. Change the aileron setting by selecting rudder 3.

Rudder deflection is defined positive with downwards deflection on the starboard wing. Deflect the aileron by 10 degrees. Regenerate the lattice and plot the geometry. The flap panels will be deflected in the geometry plot. Go directly to the solver and compute a simple solution with the jid test3. Plot the results.

To compare test2 and test3, either do a hardcopy of the results or select the keyboard access in the main menu. This will allow you to issue standard Matlab commands for analysis. At the keyboard prompt type:

K>> cd output
K>> ls
K>> load test2-Cx
K>> results

dwcond: 19.0666
F: [200x3 double]
FORCE: [-214.3197 6.8522e-015 2.7851e+003]
M: [200x3 double]
MOMENTS: [7.8870e-013 901.1217 1.0675e-013]
gamma: [200x1 double]
cp: [1x200 double]
CX: -0.0219
CY: 6.9910e-019
CZ: 0.2842
D: 29.2316
C: 6.8522e-015
L: 2.7932e+003
CL: 0.2850
CD: 0.0030
CC: 6.9910e-019
Cl: 2.0283e-018
Cm: 0.0202
Cn: 2.7452e-019
ystation: [40x1 double]
ForcePerMeter: [40x1 double]
CL_local: [40x1 double]

K>> load test3-Cx
K>> results

Some other data appear

K>> cd ..
K>> return

Comparing the two result files, especially the value of the rolling moment coefficient (result.Cl) will give you an idea on the influence of deflecting the aileron on the rolling moment.

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