Control of directional reflection and spectral characteristics on environmental surfaces by scattering medium adding microstructure

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K12231
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Environmental engineering and reduction of environmental burden
• Research Institution: Osaka Prefecture University
• Principal Investigator: Yoshida Atsumasa 大阪府立大学, 工学(系)研究科(研究院), 教授 (60174918)
• Co-Investigator(Kenkyū-buntansha): 木下 進一 大阪府立大学, 工学(系)研究科(研究院), 准教授 (70263209)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: ふく射伝熱 / 表面微細構造 / 散乱性媒体 / 反射指向性 / 波長特性 / 数値解析 / 塗膜 / 再帰性反射

Outline of Final Research Achievements

The surface materials constituting environment are generally scattering medium. It is expected that wavelength characteristic and reflection directivity can be controlled by adding regular microstructure on the surface or by dispersing particles with special material and shape in painted layer. In this study, the effect of structural parameter and incident angle on solar reflection characteristics of the surface with periodic microstructure and the effect of the kind and the particle diameter of pigment included in painted layer on its solar reflectance are numerically evaluated respectively.
In addition, in the case of a retroreflective material such that strongly reflects towards an incident direction constructed on wall surface, the radiative environment near the wall is numerically evaluated, and reduction effect on human thermal load in outdoor space by the reflection directivity control of the wall is investigated.

Free Research Field

熱工学

Academic Significance and Societal Importance of the Research Achievements

本研究の主題である種々の散乱性媒体表面に対するふく射特性制御は，地球温暖化対策の観点では，太陽エネルギー利用の高度化による化石燃料消費抑制につながること，また大都市における夏季のヒートアイランド対策の観点では，人工被覆面の日射吸収抑制に寄与する高日射反射率化と，それに伴う屋外空間のふく射環境変化に対する人体への影響抑制の相反する要求を解決できることから，重要な技術であると考える．