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Boiling regimes of HFE-7100 and water droplets at impact on a superheated surfaceстатья
Статья опубликована в высокорейтинговом журнале
Статья опубликована в журнале из списка Web of Science и/или Scopus- Авторы: Gatapova Elizaveta Ya, Sitnikov Vadim O.
- Журнал: International Journal of Thermal Sciences
- Том: 206
- Год издания: 2024
- Издательство: Elsevier BV
- Местоположение издательства: Netherlands
- Номер статьи: 109317
- DOI: 10.1016/j.ijthermalsci.2024.109317
- Аннотация: Dielectric liquid cooling represents a highly desirable solution for the cooling of electronics. One of the most effective cooling methods is spray cooling systems, which involve the droplet impact process. The methoxynonafluorobutane (HFE-7100) liquid exhibits a low latent heat of vaporization and a boiling point of 61 °C. The data on the interaction of HFE-7100 droplets with a hot surface are presented in detail for the sapphire plate temperature range of 50 to 160 °C and Weber number varying from 50 to 160 for the first time. Comparative experiments were conducted for water with substrate temperatures ranging from 120 to 240 °C and Weber numbers of 20 to 83. The various modes of droplet interaction dynamics were described and classified using top-view and side-view visualization by a high-speed camera enhanced with a stereomicroscope. The temperature of the droplet surface and substrate is measured from the top using an infrared camera with special calibration. The results are presented in a combined map of droplet dynamics and boiling regimes. The distinctive properties of HFE-7100 liquid permit the observation of all boiling regimes with significantly lower superheat than that of water. The rebound regime is observed in a wider range of Weber numbers (up to 150) than for water (up to 50). For a high Weber number and high superheat, the HFE-7100 droplet is observed to spread over the vapor layer and levitate as a very thin liquid film without bubbles, which then ruptures and atomizes into small-scale levitating droplets. For We>150, the maximum spreading diameter is found to be greater in the film boiling regime at levitation than in all other boiling regimes. A modified formula for maximum spreading diameter dependent on surface temperature is proposed. A comparison with data from the literature is also presented. The droplet surface temperature was measured using an IR camera from above. A qualitative analysis of heat transfer was conducted based on a semi-analytical model for a spreading droplet, and the results were compared with the measured droplet surface temperature. © 2024 Elsevier Masson SAS
- Добавил в систему: Гатапова Елизавета Яковлевна