Measurement of Rarefied Gas Flow by OPMS (Optical Pressure Measurement System)

通过 OPMS（光学压力测量系统）测量稀薄气体流量

• 批准号: 08650227
• 负责人: FUJIMOTO Tetsuo
• 金额: $ 1.47万
• 依托单位: Meijo University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08650227/
• 关键词: rarefied gas; pressure measurement; optical measurement; fluorescence

An optical pressure measurement system utilizing pressure sensitive paint which is based on the O_2 quenching of luminescence has been developed. The pressure sensitive paint is consist of Pt-Octaethelporphyrin or phthalocyanine as luminophore and O_2-permeable silicon polymer as matrix. Variation of strength of luminescence with change of partial pressure of oxigen is studied experimentally in the pressure range from 760 to 10^<-3> Torr and temperature range from 30 to 80 degree Celsius. A painted sample is radiated by UV light of wave length 390nm and fluorescence of wave length of 650nm from luminophore is detected by a CCD camera and the data are processed by a PC.Following results have been obtained :1.Ratio of fluorescence intensity I at pressure P to fluorescence intensity I_<ref> at a reference pressure P_<ref> satisfies the Stern-Volmer relation,<<numerical formula>>Taking into account the effect of the paint thickness, the above relation is modified, giving<<numerical formula>>However, the coefficient of square term is very small compared with the one of the linear term. The Stern-Volmer relatiion is not satisfied for P/P_<ref> less than 0.1. In this range dI/dP is large, showing the high sensitivity to the pressure.2.Absolute fluorescence intensity depends on the temperature. The relation betweem P/P_<ref> and P/P_<ref> does not depend on the temperature in the range P/P_<ref> larger than 0.1. Decrease of fluorescence with increase of temperature may be attributable to the decrease of morecular populatiion in the ground state of the luminophore.3.Absolute strength of fluorescence decreases with lapse of time, keeping the experimental condition unaltered. After 24 hours, the strength of fluorescece becomes about 80% PtOEP and about 60% for phtalocyanine. However, relation between P/P_<ref> and I/I_<ref> does not change in spite of laspe of time.

开发了一种基于O_2发光猝灭的压敏涂料光学压力测量系统。该压敏涂料以Pt-八乙基卟啉或酞菁为发光体，以透O_2硅聚合物为基体组成。实验研究了在760～10^-3Torr的压力范围和30～80℃的温度范围内发光强度随氧分压变化的变化。用波长390nm的紫外光照射涂漆样品，用CCD相机检测发光体发出的波长为650nm的荧光，并通过PC机处理数据。得到以下结果： 1.荧光强度I的比率参考压力 P_<ref> 下的压力 P 与荧光强度 I_<ref> 满足 Stern-Volmer 关系式，<<数值公式>>考虑了油漆厚度，对上述关系进行修改，给出<<数值公式>>，但是，与线性项的系数相比，平方项的系数非常小。当 P/P_<ref> 小于 0.1 时，不满足 Stern-Volmer 关系。在此范围内dI/dP较大，表现出对压力的高敏感性。2.绝对荧光强度取决于温度。 P/P_<ref> 和 P/P_<ref> 之间的关系不依赖于 P/P_<ref> 大于 0.1 的范围内的温度。荧光随着温度的升高而减弱，可能是由于发光体基态的数量减少所致。3.在实验条件不变的情况下，荧光的绝对强度随着时间的推移而减弱。 24小时后，荧光强度变为PtOEP的约80%，酞菁的荧光强度变为约60%。然而，尽管时间流逝，P/P_<ref>和I/I_<ref>之间的关系不会改变。