在高达26MPa的液压区域中,NPL (印度) 和NIST (美国) 压力标准之间的相互比较
J K N Sharma1, Kamlesh K Jain1, C D Ehrlich2
1National Physical laboratory, New Delhi, India.
概括
印度国家物理实验室 (NPL) 和美国国家标准与技术研究所 (NIST) 之间的压力测量对比显示出了很好的一致性. 结果验证了他们的活塞表压力标准在广泛范围内的准确性.
科学领域:
- 计量学 计量学 计量学
- 压力测量方法 压力测量方法
- 国家计量研究所国家计量研究所
背景情况:
- 准确的压力测量对于科学和工业应用至关重要.
- 国际相互比较对于验证国家标准至关重要.
- 活塞仪表是高压计量学的主要标准.
研究的目的:
- 为了相互比较NPL (印度) 和NIST (美国) 之间的压力测量.
- 为了验证各自活塞表压力标准的性能.
- 在6MPa至26MPa的范围内,在声明的不确定性范围内评估协议.
主要方法:
- 在NPL使用NPL和NIST活塞表压力标准进行了相互比较.
- 在6MPa至26MPa的压力范围内进行了测量.
- 关键参数比较包括零压有效面积 (A0) 和不同压力有效面积.
主要成果:
- 在由NIST标准确定的NPL标准的零压力有效面积 (A0) 中观察到1 × 10-6的相对差异.
- 有效面积的相对差异在6 MPa时从3.5 × 10-6到26 MPa时为12 × 10-6不等.
- 观察到的差异与NPL和NIST标准的独立声明的不确定性非常一致.
结论:
- 相互比较表明,NPL和NIST的压力测量能力之间存在很高的一致性.
- 结果证实了两个国家计量机构使用的活塞表压力标准的可靠性和准确性.
- 这种相互比较为两家实验室之间高压测量的可追溯性和一致性提供了信心.
相关概念视频
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