Evaluating the freeze–thaw phenomenon in sandwich-structured composites via numerical simulations and infrared thermography
Article (2,783Mb) (Restricted access) Request copy
Què és aquest botó?
Aquest botó permet demanar una còpia d'un document restringit a l'autor. Es mostra quan:
- Disposem del correu electrònic de l'autor
- El document té una mida inferior a 20 Mb
- Es tracta d'un document d'accés restringit per decisió de l'autor o d'un document d'accés restringit per política de l'editorial
Rights accessRestricted access - publisher's policy (embargoed until 2021-08-01)
The water ingress phenomenon in sandwich-structured composites used in the aerospace/aeronautical sector is a current issue. This type of defect can cause in the course of time several other defects at the boundary, such as corrosions, deformations, detachments. In fact, water may change its state of physical matter going towards the freeze–thaw cycle caused by the atmosphere re-entry of, e.g. space probes. In this work, the alveoli of a composite laminate have been filled with water, which was initially transformed into ice. By taking into account, the known quantity of water, the freeze–thaw cycle was simulated by Comsol Multiphysics® software, reproducing exactly the shape of the sandwich as well as the real conditions in which it was subsequently subjected in a climatic chamber. The experimental part consisted of monitoring the front side of the specimen by means of a thermal camera operating into the long-wave infrared spectrum, and by setting both the temperature and the relative humidity of the test chamber according to the values imposed during the numerical simulation step. It was found that the numerical and experimental temperature trends are in good agreement with each other since the model was built by following a physico-chemical point-of-view. It was also seen that the application of the independent component thermography (ICT) technique was able both to retrieve the positions of the defects (i.e. the water inclusions) and to characterize the defects in which a detachment (fabricated between the fibres and the resin) is present; the latter was realized above an inclusion caused by the water ingress. To the best of our knowledge, this is the first time that ICT is applied to satisfy this purpose.
CitationSfarra, S. [et al.]. Evaluating the freeze–thaw phenomenon in sandwich-structured composites via numerical simulations and infrared thermography. "Journal of thermal analysis and calorimetry", 13 Juliol 2020, p. 1-19.
|Paper_Sfarra et al_JTAC_final version_shared-1.pdf||Article||2,783Mb||Restricted access|
All rights reserved. This work is protected by the corresponding intellectual and industrial property rights. Without prejudice to any existing legal exemptions, reproduction, distribution, public communication or transformation of this work are prohibited without permission of the copyright holder