29 Sep 2018
We are working on modeling cross-sections of a realistic wing with Pre-VABS and VABS. The wing has a prescribed twist at each cross-section. My understanding is that the pre-twist is only entered in the VABS input file as value of kappa_1 and it shouldn’t effect the coordinates we define in PreVABS. Because Pre-VABS works with a local frame of reference (z, in the new manual). Is this correct?
Also, the wing we are working with is swept-back. I am assuming this will only effect the 1D analysis and there is no place in VABS to take the sweep angle into account. Am I correct?
Thank you in advance.
01 Oct 2018
You are correct for the pre-twist setting. As for the sweep of the wing, you are correct that the sweep angle is defined in the global 1D beam analysis. However, you may need to set the oblique of the cross section, depending on whether your cross section is defined parallel to the airflow or perpendicular to the reference line of the wing.