Author, as appears in the article.: Jna. Gavaldà; Nuria Sáez; X. Ruiz; Valentina Shevtsova
Department: Química Física i Inorgànica
URV's Author/s: GAVALDÀ MARTÍNEZ, JOSEFA; Nuria Sáez; RUIZ MARTÍ, JOSÉ JAVIER; Valentina Shevtsova
Abstract: The present work aims to study mechanical nonlinearities detected in the accelerometric
records during a thermodiffusion experiment performed at the International Space
Station, ISS. In that experiment the test cell was subjected to harmonic vibrations of
different frequencies and amplitudes. Accelerometric data associated to the runs were
downloaded from NASA PIMS website. Second order spectral analysis shows that the
shaker modifies the normality of the data and introduces nonlinearities in the distribution
of energy. High Order Spectral Analysis, HOSA, based on the bispectrum, bicoherence,
trispectrum and tricoherence functions enabled us to study the kind of these nonlinearities.
Additionally, a new method using the biphase and triphase histograms helps us to
assess if quadratic and/or cubic phase coupling mechanisms are responsible for the
anomalous nonlinear energy transfer detected. Finally, the RMS acceleration values are
investigated to check if the vibratory limit requirements of the ISS are exceeded. This
methodology is important not only in generic research of aerospace engineering but also
in space sciences in order to help space researchers to characterize more globally their
experiments. It is mentioned finally that HOSA techniques are not new, but never have
been used in the analysis of accelerometric data coming from the ISS
Research group: Processat Digital de Senyals en Entorns Aeroespacials i Biomèdics
Thematic Areas: Física Física Physics
licence for use: https://creativecommons.org/licenses/by/3.0/es/
ISSN: 0094-5765
Author identifier: 0000-0001-7881-4192; ; 0000-0003-4020-4457;
Record's date: 2018-03-07
Last page: 25
Journal volume: 103
Papper version: info:eu-repo/semantics/submittedVersion
Funding program: altres; 2014SGR365
Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
Entity: Universitat Rovira i Virgili
Journal publication year: 2014
First page: 16
Publication Type: Article Artículo Article
Repositori URV