Coupling Calculation for Radiative and Convective Heat Transfer and Development of Mist Cooling Technology to Prevent Heat Stroke

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14087
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 19020:Thermal engineering-related
• Research Institution: Yamagata University
• Principal Investigator: Gonome Hiroki 山形大学, 大学院理工学研究科, 准教授 (80785551)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 消防装置 / ふく射 / ミスト

Outline of Final Research Achievements

The objective of this study was to realize active control of the flow field and shielding of thermal radiation by water mist. A heat transfer analysis code that can describe the non-gray absorption and non-isotropic scattering characteristics of the scattering medium was established, and a combined convection-radiation heat transfer analysis with water mist was performed. It was shown that the inclusion of mist suppresses the turbulent fluctuation of temperature near the wall and contributes to the suppression of the radiative heat transfer. In addition, water mist spraying experiments were conducted to measure the particle size distribution of water droplets in the mist layer and to experimentally evaluate the radiative shielding performance. The results showed that the radiative shielding rate of the mist layer is dependent on the water droplet diameter, and that a smaller droplet diameter is more effective for radiative shielding.

Free Research Field

ふく射伝熱

Academic Significance and Societal Importance of the Research Achievements

ミスト冷却装置は都市環境技術としての用途のみならず、高温環境が日常の製造現場（製鉄所等）での導入が考えられる。高温環境ではふく射伝熱が支配的になるので、それを防ぐ商品を開発し、過酷な環境での労働負荷を軽減できる可能性がある。また、同じくふく射伝熱が支配的になる環境として火災現場が挙げられる。目に見える炎に加え、目に見えない熱ふく射も消火活動において多大な影響を持つ。この熱ふく射による延焼や火傷等を防ぐ消防設備の実現が望まれており、スプリンクラー等の消火設備に本研究知見を応用することでふく射熱遮断機能も持つ防火設備が実現できる。