Microwave-cavity measurements for gas thermometry up to the copper point

被引：20

作者：

Feng, XiaoJuan ^{[1
]}

Gillis, Keith A. ^{[2
]}

Moldover, Michael R. ^{[2
]}

Mehl, James B. ^{[2
]}

机构：

[1] Natl Inst Metrol, Beijing 100013, Peoples R China

[2] NIST, Gaithersburg, MD 20899 USA

来源：

METROLOGIA | 2013年 / 50卷 / 03期

基金：

中国国家自然科学基金;

关键词：

RELATIVE PERMITTIVITIES; RESONATOR;

D O I：

10.1088/0026-1394/50/3/219

中图分类号：

TH7 [仪器、仪表];

学科分类号：

0804 ; 080401 ; 081102 ;

摘要：

This work explores the feasibility of acoustic gas thermometry (AGT) in the range 700 K to the copper point (1358 K) in order to more accurately measure the differences between ITS-90 and the thermodynamic temperature. To test material suitability and stability, we investigated microwave resonances in argon-filled cylindrical cavities machined from a Ni-Cr-Fe alloy. We measured the frequencies of five non-degenerate microwave modes of one cavity at temperatures up to 1349 K using home-made coaxial cables and antennas. The short-term repeatability of both the measured frequencies f(N) and the scaled half-widths g(N)/f(N) was better than 10(-6) f(N). Oxidation was not a problem while clean argon flowed through the cavity. The measurement techniques are compatible with highly accurate AGT and may be adaptable to refractive index gas thermometry.

引用

页码：219 / 226

页数：8

共 16 条

[1]

BIPM, 1990, SUPPL INF INT TEMP S, P13

[2]

Collin R. E., 2001, Foundations for Microwave Engineering, V2nd

[3] THE VELOCITY OF PROPAGATION OF ELECTROMAGNETIC WAVES DERIVED FROM THE RESONANT FREQUENCIES OF A CYLINDRICAL CAVITY RESONATOR [J].