並列タイトル等Direct observation of Piston Effect in a critical fluid
タイトル（掲載誌）宇宙航空研究開発機構特別資料: 平成16年度総合技術研究本部宇宙領域宇宙科学研究本部合同研究成果報告書:先行研究等 = JAXA Special Publication: FY2004 Report of Joint Research Achievements of the Space Division of Institute of Aerospace Technology and Institute of Space and Astronautical Science: Pioneering Research
一般注記出版タイプ： NA
Thermal energy applied to a pure fluid near its critical point immediately makes a strong expansion. This causes an adiabatic compression in the front of the expansion and a large density difference is formed there. The difference with adiabatic energy is transported as an acoustic wave. This rapid heat transportation is called 'Piston Effect'. In our study, an ultra-sensitive and high-speed density measurement system was developed to conduct a quantitative measurement of the 'Piston Effect'. By using the system, we succeeded to directly observe the elementary process of 'Piston Effect'. To demonstrate the performance of the system, the measurement of sound velocity in a critical fluid was conducted. Using the FFT method to the experimental results, the sound velocity could be precisely evaluated. The velocity profile versus temperature from the experimental results shows a good agreement with the simulation results and theoretical prediction, that is, the profile should have the scale universality. However, the profile from the experimental results obeys another scale universality if T-T(sub c) is less than 0.1 K. These indicate that our experimental system enables us to quantitatively discuss the critical phenomena.
資料番号: AA0049057017
レポート番号: JAXA-SP-05-011
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）
提供元機関・データベース宇宙航空研究開発機構 : 宇宙航空研究開発機構リポジトリ