In design and certification of spacecraft, payload/launcher coupled loads analyses are performed to simulate the satellite dynamic environment. In order to obtain accurate predictions, the system damping properties must be properly taken into account in the finite element model used for coupled loads analysis. This is typically done using a structural damping characterization in the frequency domain, which is not applicable in the time domain. Therefore, the structural damping matrix of the system must be converted into an equivalent viscous damping matrix when a transient coupled loads analysis is performed. This paper focuses on the validation of equivalent viscous damping methods for dynamically condensed finite element models via correlation with experimental data for a realistic structure representative of a slender launch vehicle with solid rocket motors. A second scope of the paper is to investigate how to conveniently choose a single combination of Young's modulus and structural damping coefficient - complex Young's modulus - to approximate the viscoelastic behavior of a solid propellant material in the frequency band of interest for coupled loads analysis. A scaled-down test article inspired to the Z9-ignition Vega launcher configuration is designed, manufactured, and experimentally tested to obtain data for validation of the equivalent viscous damping methods. The Z9-like component of the test article is filled with a viscoelastic material representative of the Z9 solid propellant that is also preliminarily tested to investigate the dependency of the complex Young's Modulus on the excitation frequency and provide data for the test article finite element model. Experimental results from seismic and shock tests performed on the test configuration are correlated with numerical results from frequency and time domain analyses carried out on its dynamically condensed finite element model to assess the applicability of different equivalent viscous damping methods to describe damping properties of slender launch vehicles in payload/launcher coupled loads analysis.

Experimental validation of solid rocket motor damping models / Riso, Cristina; Fransen, Sebastiaan; Mastroddi, Franco; Coppotelli, Giuliano; Trequattrini, Francesco; De Vivo, Alessio. - In: CEAS SPACE JOURNAL. - ISSN 1868-2502. - STAMPA. - 10:2(2018), pp. 213-230. [10.1007/s12567-017-0191-3]

Experimental validation of solid rocket motor damping models

Cristina Riso
Membro del Collaboration Group
;
Franco Mastroddi
Project Administration
;
Giuliano Coppotelli
Membro del Collaboration Group
;
FrancescoTrequattrini
Membro del Collaboration Group
;
2018

Abstract

In design and certification of spacecraft, payload/launcher coupled loads analyses are performed to simulate the satellite dynamic environment. In order to obtain accurate predictions, the system damping properties must be properly taken into account in the finite element model used for coupled loads analysis. This is typically done using a structural damping characterization in the frequency domain, which is not applicable in the time domain. Therefore, the structural damping matrix of the system must be converted into an equivalent viscous damping matrix when a transient coupled loads analysis is performed. This paper focuses on the validation of equivalent viscous damping methods for dynamically condensed finite element models via correlation with experimental data for a realistic structure representative of a slender launch vehicle with solid rocket motors. A second scope of the paper is to investigate how to conveniently choose a single combination of Young's modulus and structural damping coefficient - complex Young's modulus - to approximate the viscoelastic behavior of a solid propellant material in the frequency band of interest for coupled loads analysis. A scaled-down test article inspired to the Z9-ignition Vega launcher configuration is designed, manufactured, and experimentally tested to obtain data for validation of the equivalent viscous damping methods. The Z9-like component of the test article is filled with a viscoelastic material representative of the Z9 solid propellant that is also preliminarily tested to investigate the dependency of the complex Young's Modulus on the excitation frequency and provide data for the test article finite element model. Experimental results from seismic and shock tests performed on the test configuration are correlated with numerical results from frequency and time domain analyses carried out on its dynamically condensed finite element model to assess the applicability of different equivalent viscous damping methods to describe damping properties of slender launch vehicles in payload/launcher coupled loads analysis.
2018
coupled loads analysis; equivalent viscous damping; structural damping; solid rocket motors: viscoelastic materials
01 Pubblicazione su rivista::01a Articolo in rivista
Experimental validation of solid rocket motor damping models / Riso, Cristina; Fransen, Sebastiaan; Mastroddi, Franco; Coppotelli, Giuliano; Trequattrini, Francesco; De Vivo, Alessio. - In: CEAS SPACE JOURNAL. - ISSN 1868-2502. - STAMPA. - 10:2(2018), pp. 213-230. [10.1007/s12567-017-0191-3]
File allegati a questo prodotto
File Dimensione Formato  
Riso_Experimental-validation_2018.pdf

solo gestori archivio

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 4.02 MB
Formato Adobe PDF
4.02 MB Adobe PDF   Contatta l'autore

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1043114
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 6
  • ???jsp.display-item.citation.isi??? 4
social impact