3D microstructure evolution of ice in jet A-1 fuel as a function of applied temperature over time

• Published in: International journal of heat and mass transfer 2022-02, Vol.183, p.122158, Article 122158
• Main Authors: Haffar, Iheb, Flin, Frédéric, Geindreau, Christian, Petillon, Nicolas, Gervais, Pierre-Colin, Edery, Vincent
• Format: Article
• Language: English
• Subjects: 3D evolution; Aircraft fuel systems; Aviation fuel; Engineering Sciences; Evolution; Ice; Ice crystals; Image processing; Jet engine fuels; Jet fuel; Microstructure; Morphology; Nucleation; Temperature; Temperature effects; Time-lapse; Tomography
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/j.ijheatmasstransfer.2021.122158

•A method to characterize the 3D morphological evolution of ice in jet fuel as a function of temperature is proposed.•3D images of the sample are obtained by X-ray tomography using a dynamic cryogenic cell.•Image processing and analysis give access to the local 3D displacement measurement.•The settling and sintering effects are enhanced between −10 and −5 ∘C. [Display omitted] Temperature (θ) and time are key factors in both nucleation and evolution of ice crystals in jet fuels occurring inside aircraft fuel systems. In this study, we followed the morphological evolution of an ice agglomerate in jet A-1 fuel using a specific dynamic cryogenic cell (CellDyM). An in vivo experiment was conducted, imposing temperatures between −45 ∘C and −5 ∘C, while performing X-ray scans throughout the experiment. Then, image processing and analysis provided access to the morphological evolution of the ice sample, at a resolution of 7.5 μm. Three types of analyses were mainly computed: (i) cumulative evolution of the microstructure as a function of temperature and time intervals, (ii) evolution of the ice microstructure for isothermal conditions and (iii) evolution of the microstructure for different temperature jumps. Overall, the effect of temperature is minor in the θ interval of [−45, −10] ∘C, with evolution rates between 1.6 and 4.6 μm.h−1, compared to the θ interval of [−10, −5] ∘C, during which a significant change in the morphology of the ice agglomerate was observed, with an evolution rate of 10.4 μm.h−1. This study illustrates the key values of the temperature ranges that influence the ice microstructure in jet fuel and brings new insights on the physical mechanisms potentially involved.