Transient Boiling Heat Transfer Characteristics of a Moving Hot Surface during Two-fluid Flat Spray Quenching

DOI Web Site Web Site 16 References
  • Niitani Hiroshi
    Graduate School of Science and Engineering, Saga University Research & Development, Process Research Laboratories, Nippon Steel Corporation
  • Mitsutake Yuichi
    Institute of Ocean Energy, Saga University

Bibliographic Information

Other Title
  • 二流体フラットスプレー冷却実験における移動高温鋼材の非定常沸騰熱伝達特性
  • ニリュウタイ フラットスプレー レイキャク ジッケン ニ オケル イドウ コウオン コウザイ ノ ヒテイジョウ フットウ ネツ デンタツ トクセイ

Search this article

Abstract

<p>In the hard cooling process of steel, heat flux and temperature fluctuations are so large due to the wetting that it is difficult to measure unsteady cooling phenomena. In this study, we experimentally analyzed the detailed heat transfer behavior of continuous casting secondary cooling of a moving system using the improved IHCP (Inverse heat conduction problem) analysis with the Laplace transform technique developed in the previous paper. The test piece was a SUS304 rotor with a thickness of 10 mm and an outer diameter of 136 mm, which was heated to 880°C, rotated at a peripheral speed of 0.9 to 8.0 m/min, and cooled from above with a flat air mist spray. Thermocouples were installed at two points 1.5 mm and 3.5 mm from the surface. As a result of the analysis, under the conditions of the film boiling region, the surface heat flux qw could be expressed as qw / qw,peak = (W / Wpeak)0.57 using the spray water flux W. However, after the start of wetting, cooling continued even on the downstream side in the moving direction where the water droplets did not collide directly. In the nucleate boiling region and the film boiling region, the average heat flux when passing through the spray did not change due to the change in casting speed. However, the wetting start temperature became higher as the casting speed becomes slower.</p>

Journal

  • Tetsu-to-Hagane

    Tetsu-to-Hagane 108 (1), 1-10, 2022

    The Iron and Steel Institute of Japan

References(16)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top