Modeling the Dynamic Behavior of an Inflatable Rigidized Boom in Exposure to Temperature Changes in Space

2009 ◽  
Author(s):  
Neda Darivandi ◽  
Armaghan Salehian
Keyword(s):  
Frequency Response ◽  
Dynamic Behavior ◽  
Thermal Loading ◽  
Response Functions ◽  
Frequency Response Functions ◽  
Temperature Changes ◽  
The Past ◽  
Space Industry

During the past few years inflatable technology has received much attention by space industry due to its significantly reduced launch volume and mass. While this technology meets the mass goals, because of being ultra-light the structures become very susceptible to disturbances in space. One of the main sources of disturbances is the abrupt temperature changes for a satellite upon passing the Earth’s shadow. While much research has been carried out on the static thermal loading for such structures, very little is known about their dynamic behavior with respect to temperature changes. The presented work is intended to fill this gap. The frequency response functions for a 3 meter inflatable rigidized boom for various temperatures are studied and compared using FEA models in ABAQUS.

Frequenzgangmessung an Spindeln unter Drehzahl*/FRF Measurement on rotating spindles

2017 ◽  
Vol 107 (05) ◽  
pp. 318-322
Author(s):  
C. Prof. Brecher ◽  
S. Neus ◽  
H.-M. Eckel ◽  
T. Motschke ◽  
M. Fey
Keyword(s):  
Frequency Response ◽  
Dynamic Behavior ◽  
Rotational Speed ◽  
Machine Tools ◽  
Displacement Measurement ◽  
Response Functions ◽  
Frequency Response Functions ◽  
Technical Article ◽  
Force Excitation ◽  
Contact Displacement

Das statische und dynamische Verhalten von Hauptspindelsystemen ist über Nachgiebigkeitsfrequenzgänge beschreibbar. Dabei beeinflussen Drehzahleffekte die dynamischen Nachgiebigkeiten des Systems Werkzeug – Werkzeugschnittstelle – Spindel maßgeblich. Dieser Fachartikel beschreibt eine Methodik zur messtechnischen Ermittlung von Nachgiebigkeitsfrequenzgängen an rotierenden Spindeln mit absoluter sowie relativer Kraftanregung in Verbindung mit berührungsloser Verlagerungsmessung.   The static and dynamic behavior of main spindles in machine tools can be described via Frequency Response Functions (FRFs). Dynamic compliances of the system tool-interface-spindle are decisively influenced by rotational speed effects. This technical article describes a methodology for FRF measurement of rotating spindles with absolute and relative force excitation in conjunction with non-contact displacement measurement.

Predicting the Dynamic Behavior of a Coupled Structure Using Frequency-Response Functions

2002 ◽  
Vol 39 (1) ◽  
pp. 109-113 ◽  
Author(s):  
T. P. Gialamas ◽  
D. A. Manolas ◽  
D. T. Tsahalis
Keyword(s):  
Frequency Response ◽  
Dynamic Behavior ◽  
Response Functions ◽  
Frequency Response Functions

scholarly journals Identification of relevant acoustic transfer paths for WT drivetrains with an operational transfer path analysis

2021 ◽  
Author(s):  
W. Schünemann ◽  
R. Schelenz ◽  
G. Jacobs ◽  
W. Vocaet
Keyword(s):  
Path Analysis ◽  
Wind Turbine ◽  
Frequency Response ◽  
Mechanical System ◽  
Reference Point ◽  
Response Functions ◽  
Frequency Response Functions ◽  
Transfer Path ◽  
Transfer Path Analysis ◽  
Turbine Model

AbstractThe aim of a transfer path analysis (TPA) is to view the transmission of vibrations in a mechanical system from the point of excitation over interface points to a reference point. For that matter, the Frequency Response Functions (FRF) of a system or the Transmissibility Matrix is determined and examined in conjunction with the interface forces at the transfer path. This paper will cover the application of an operational TPA for a wind turbine model. In doing so the path contribution of relevant transfer paths are made visible and can be optimized individually.

Calculation of Component Mode Synthesis Matrices From Measured Frequency Response Functions, Part 2: Application

1998 ◽  
Vol 120 (2) ◽  
pp. 509-516 ◽  
Author(s):  
J. A. Morgan ◽  
C. Pierre ◽  
G. M. Hulbert
Keyword(s):  
Frequency Response ◽  
Coupled System ◽  
Companion Paper ◽  
Component Mode Synthesis ◽  
Response Functions ◽  
Frequency Response Functions ◽  
Measured Frequency ◽  
Measured Frequency Response ◽  
Coupled Beams ◽  
The Individual

This paper demonstrates how to calculate Craig-Bampton component mode synthesis matrices from measured frequency response functions. The procedure is based on a modified residual flexibility method, from which the Craig-Bampton CMS matrices are recovered, as presented in the companion paper, Part I (Morgan et al., 1998). A system of two coupled beams is analyzed using the experimentally-based method. The individual beams’ CMS matrices are calculated from measured frequency response functions. Then, the two beams are analytically coupled together using the test-derived matrices. Good agreement is obtained between the coupled system and the measured results.

Experimental Study for Extraction of Normal Modes

1995 ◽  
Author(s):  
S. Y. Chen ◽  
M. S. Ju ◽  
Y. G. Tsuei
Keyword(s):  
Frequency Response ◽  
Normal Mode ◽  
Normal Modes ◽  
Measurement Data ◽  
Mode Shapes ◽  
Complex Frequency ◽  
Response Functions ◽  
Frequency Response Functions ◽  
Incomplete System ◽  
Coupled Structures

Abstract A frequency-domain technique to extract the normal mode from the measurement data for highly coupled structures is developed. The relation between the complex frequency response functions and the normal frequency response functions is derived. An algorithm is developed to calculate the normal modes from the complex frequency response functions. In this algorithm, only the magnitude and phase data at the undamped natural frequencies are utilized to extract the normal mode shapes. In addition, the developed technique is independent of the damping types. It is only dependent on the model of analysis. Two experimental examples are employed to illustrate the applicability of the technique. The effects due to different measurement locations are addressed. The results indicate that this technique can successfully extract the normal modes from the noisy frequency response functions of a highly coupled incomplete system.

Sign in / Sign up

Export Citation Format

Share Document