Aeroelastic Prediction Workshop

HIRENASD Beam FEM

A dataset shared by CAROL WIESEMAN, updated on Jul 05, 2011

Summary

Contributing Author(s) :: Carol Wieseman

This contains attempts to create BEAM FEM model.

I have started a Blog to discuss this... please put your comments there and I will attempt to keep everything updated. Correspondence between A.B. and CDW is provided to assist in developing NASTRAN Beam FEM

(through July 1)(PDF)

The original data provided by Alexander is shown in
model_input-extract.txt

Additional files loaded July 21, 2011:

Comparison of Wing Masses, and Lengths, and Mass calculated from provided densities, and lengths

Comparison of Model Masses and frequencies

Emails dealing with offsets for bending and center of mass (between Proctor and Wieseman)

Spreadsheet that contains element beam properties used for debugging

One element beam model to check beam stiffnesses

Email correspondence as of July 28, 2011 - includes a cursory check of the bending and center of mass locations.

X1,X2,X3	Inertias/Kappa	Mode 1 Freq, Hz	Mode 2 Freq, Hz	File name (ms103_beam_)
1,0,0	modified	26.37854	83.69360	100_modi_ccs_o1_k_nsm1_nm1
1,0,0	modified/Beam properties modified	26.37855	83.69344	100_modi_ccs_o1_k2_nsm1_nm1
cosa,0,-sina	as provided	26.37949	83.69533	ca_0_nsa_ccs_o1_k_nsm1_nm1
cosa,0,-sina	as provided	26.37949	83.69533	ca_0_nsa_ccs_o1_k_nsm1_nm1

Below are frequencies with different permutations of

X1,X2,X3 definitions on CBEAM card
A) - 1,0,0 or
B) ca_0_nsa = cos(alpha),0,-sin(alpha) or
C)nca_0_sa = -cos(alpha),0,sin(alpha) on the beam card

coordinate system (CCS) is converted from original

O1 indicates that offsets W1-W3 were included between the node and the shear center

nsm1 = beam density is unchanged and includes the non-structural mass

nsm2 = non-structural mass is separated from the beam mass density

nm = calculation of offset N1,N2 for beginning and end of each beam segment is performed - different ways depending on the index

modi = inertias provided by Boucke were modified by the alpha.

k = kappa(K1,K2) were included in the model - values provided by Boucke (A.B.)

k2 = kappa(K1/K2) modified along with beam properties per equations provided by A.B.

Description

	1st mode	2nd mode
Boucke provided frequencies	25.33879547	78.63642299
100_modi_ccs_o1_k2_nsm1_nm1	26.37855	83.69344
100_modi_ccs_o1_k_nsm1_nm1	26.37854	83.6936
ca_0_nsa_ccs_o1_k_nsm1_nm1	26.37949	83.69533
ca_0_nsa_modi_ccs_o1_k2_nsm1_nm1	26.3795	83.69762
ca_0_nsa_modi_ccs_o1_k_nsm1_nm1	26.37949	83.69778
nca_0_sa_ccs_o1_k	26.37466	83.62444
nca_0_sa_ccs_o1_k_nsm1_nm1	26.33955	82.98219
nca_0_sa_ccs_o1_k_nsm1_nm2	26.3778	83.67184
nca_0_sa_ccs_o1_k_nsm2_nm1	26.3452	83.07531
nca_0_sa_ccs_o1_k_nsm2_nm2	26.37785	83.6722
nca_0_sa_modi_ccs_o1_k_nsm1_nm1	26.33953	82.98429

Matlab code has been requested that reads the input deck. This code also does some debugging and calculation. The disclaimer is that it isn't easy to read. If you find a coding error please let me know. There are two codes - one for reading that also does some distance calculations and then a code that writes the BDF file.

show more info

Operating System: N/A (edit)
License: N/A (edit)
Programming Language: N/A (edit)
Version: N/A (edit)

Source Files

model_input-extract.txt Beam Data provided by A. Boucke	40.2 KB	131 downloads
spccards.bdf include file required for nastran	62 bytes	107 downloads
image001.png	31.9 KB	72 downloads
image002.png	26.6 KB	42 downloads
CBEAM.png	25.0 KB	288 downloads
WingMassLength_Comparisons.xls Comparison of Masses provided in comments with calculated using provided densities, provided and calculated lengths	60.0 KB	104 downloads
Compare_W_eig_20110720.xlsx.pdf Comparison of Masses and Frequencies	19.5 KB	81 downloads
LP_CDW_emails.pdf Emails dealing with offset calculations of Beam model predominantly	826.9 KB	97 downloads
ms103_modi_o1_nsm1.bdf Latest FEM - double precision	25.9 KB	93 downloads
ms103_modi_o1_nsm1_modrho.bdf Latest FEM - double precision (modified density)	25.9 KB	96 downloads
BeamProperties_modrho.xlsx Beam Properties - debugging of Beam model	74.4 KB	111 downloads
OneElement_TipLoad.bdf Nastran input file with tip load applied at Grid #23	2.4 KB	90 downloads
StructuralAnalysisStatus.pdf Slides presented on telecon	54.6 KB	109 downloads
Emails_20110728.pdf	390.4 KB	101 downloads
Emails_AB_CDW.pdf	186.8 KB	114 downloads