Experimental study of delaying effect of the frost formation on cryogenic heat exchanger tube surfaces using super-hydrophobicity tube by anodic oxidation method

Satoru Tokawa, Yoshiaki Kinoshita, Takumi Kurata, Ryuma Osumi, Tetsuya Satou

    Research output: Contribution to conferencePaper

    Abstract

    JAXA is developing the pre-cooled turbojet engine (PCTJ) operated from sea-level static to Mach 5 with the single mechanism. The key technology of PCTJ is the precooler, which is a heat exchanger to cool down the heated incoming air using liquid hydrogen fuel. Frosting on the precooler tube surface is a major problem and some countermeasures have been proposed such as the liquid oxygen injection, methanol injection, high speed air-jet injection, and so on. However, these methods require additional mechanisms increasing the engine weight with their complicated systems. Here, we focus on the surface treatment that does not need any additional mechanism. We made aluminum super-hydrophobicity tubes treated by anodic oxidation and fluorine addition. Our method attains the super-hydrophobicity with about 157 degrees contact angle. The frost formation test using liquid nitrogen was conducted in the wind tunnel. As the results, the total amount of the frost formation can be reduced by about 17% at maximum compared with the untreated tube. However, little improvement on the heat transfer rate was found because the frost density was reduced by super-hydrophobicity.

    Original languageEnglish
    Publication statusPublished - 2018 Jan 1
    Event9th Asian Conference on Refrigeration and Air-Conditioning, ACRA 2018 - Sapporo, Hokkaido, Japan
    Duration: 2018 Jun 102018 Jun 13

    Other

    Other9th Asian Conference on Refrigeration and Air-Conditioning, ACRA 2018
    CountryJapan
    CitySapporo, Hokkaido
    Period18/6/1018/6/13

      Fingerprint

    Keywords

    • Anodic Oxidation
    • Cryogenic
    • Frost
    • Heat Exchanger
    • Super-Hydrophobicity

    ASJC Scopus subject areas

    • Control and Systems Engineering
    • Condensed Matter Physics
    • Electrical and Electronic Engineering
    • Mechanical Engineering

    Cite this

    Tokawa, S., Kinoshita, Y., Kurata, T., Osumi, R., & Satou, T. (2018). Experimental study of delaying effect of the frost formation on cryogenic heat exchanger tube surfaces using super-hydrophobicity tube by anodic oxidation method. Paper presented at 9th Asian Conference on Refrigeration and Air-Conditioning, ACRA 2018, Sapporo, Hokkaido, Japan.