Effect of slenderness ratio

[shishirsanjeeva]

Hi
I used a Ross example, and upon checking the slenderness ratio, I noticed that the rotor is highlighted in yellow. Could you please explain how this affects the analysis results and how I can avoid this issue?

from pathlib import Path
import ross as rs
import numpy as np

import plotly.io as pio
pio.renderers.default = "browser"

rotor= rs.compressor_example()
print("Rotor total mass = ", np.round(rotor.m, 2))

rotor.plot_rotor(check_sld=True).show()  # Plot the rotor model

[ViniciusTxc3]

Hi @shishirsanjeeva ,
In documentation we have an Example 2 - Effect of varying slenderness ratio that shows this effect.
As the slenderness ratio increases, the error in natural frequencies also increases, especially if the number of shaft elements is small. For high slenderness ratios (e.g., >1.6), it is recommended to use more elements and include shear and rotary inertia effects.

[shishirsanjeeva]

Hi @ViniciusTxc3
Thanks for the support. Already some elements are very slender i.e. L/D ratio is low. Further by increasing the elements, the slenderness ratio will further decrease. Kindly, requesting your help on this.