2021 Fiscal Year Final Research Report
Gas-phase multi-component diffusion model with intrinsic diffusion coefficients for reasonable explanation of the phenomenon
Project/Area Number |
19K05127
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Review Section |
Basic Section 27010:Transport phenomena and unit operations-related
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Research Institution | Kagoshima University |
Principal Investigator |
Kai Takami 鹿児島大学, 理工学域工学系, 教授 (00177312)
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Project Period (FY) |
2019-04-01 – 2022-03-31
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Keywords | 拡散 / 非等モル拡散 / 多成分系拡散 / 分子拡散域 / Grahamの法則 |
Outline of Final Research Achievements |
It was reported in 1833 that gas-phase two-component interdiffusion in porous media under isobaric conditions was non-equimolar diffusion. Although this phenomenon has been known as Graham’s law, the mechanism has not been correctly explained. In addition, gas diffusion in multi-component systems is currently explained by combining the equimolar interdiffusion coefficients between the two components, which does not reflect the phenomenon. In this study, we extended the model to gas-phase multicomponent diffusion by introducing molecular-specific diffusion coefficients and taking into account the collision frequency between different molecules depending on their compositions. Comparison of the calculations by the model with experimental results in a constant volume system shows the validity of the model, including the interpretation of phenomena that cannot be explained by Fick's law.
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Free Research Field |
化学工学
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Academic Significance and Societal Importance of the Research Achievements |
多成分系拡散は等モル相互拡散係数を組み合わせて説明がなされている。しかし、この考え方では1833年に発見された分子拡散域にある細孔内での等圧非等モル拡散が説明できない。そこで二成分系に対してすでに提案している分子固有の拡散係数を使ったモデルを三成分系へ拡張し、浸透拡散、逆拡散および拡散障壁などFickの法則では説明できない現象を正しく表現することができた。多孔質触媒、燃料電池の電極やマイクロチャンネルなどの微小空間での多成分拡散現象を正確に記述することは今後ますます重要になってくると思われる。このような現象の評価に設計ツールとして化学工学の考え方を生かす際に本研究の成果は役立つと考えられる。
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