how to get wd in run_modal() only whirling freqency , not axial and torsional's

[Pierre-zhu]

all already 6dof in last ross ,
how to get wd in rotor.run_modal() only whirling frequency? thanks for help.
modal = rotor.run_modal(rotor_speed,num_modes=24)

[jguarato]

You can filter frequencies by the mode type attribute ("Lateral", "Axial", "Torsional"), for example:

whirling_frequency = np.array([
    modal.wd[i] for i, shape in enumerate(modal.shapes) if shape.mode_type == "Lateral"
])

[Pierre-zhu]

Thanks for your help!

[Pierre-zhu]

Another question as following regarding campbell data rotor.run_campbell(),
How could be show me in fig only whirling (forward and backward)? or can I get data only whirling (forward and backward)?
Thanks.

[Pierre-zhu]

You can filter frequencies by the mode type attribute ("Lateral", "Axial", "Torsional"), for example:

whirling_frequency = np.array([
    modal.wd[i] for i, shape in enumerate(modal.shapes) if shape.mode_type == "Lateral"
])

Another question as following regarding campbell data rotor.run_campbell(),
How could be show me in fig only whirling (forward and backward)? or can I get data only whirling (forward and backward)?
can I make decided which one is lateral from campbell.wd?
Thanks.

[jguarato]

I'm not sure if I understand your question.

Regarding the Campbell Diagram figure, a direct filter can be applied on the figure information to remove the "Axial" and "Torsional" modes:

fig = campbell.plot()

for trace in fig["data"]: 
    if trace["name"] in ["Torsional", "Axial"]: 
        trace["visible"] = False

fig.show()

Additionally, you can get the modal analysis results for each rotor speed with campbell.modal_results dict:

speed = 1140 # a speed belonging to the speed_range array (argument of run_campbell)
modal = campbell.modal_results[speed]

whirling_frequency = np.array([
    modal.wd[i] for i, shape in enumerate(modal.shapes) if shape.mode_type == "Lateral"
])

[Pierre-zhu]

thanks for your answer so quickly!
According your guid, I write as flowing:

campbell_wd_whirlAll=[]
for key in campbell.modal_results:
	campbell_wd_whirlAll.append(np.array([campbell.modal_results[key].wd[i] for i, shape in enumerate(campbell.modal_results[key].shapes) if shape.mode_type == "Lateral"]))
campbell_wd_whirlAll=np.array(campbell_wd_whirlAll)

Thats ok now