论文标题
使用初级活塞量规实现PPM水平压力稳定性
Realization of ppm level pressure stability for primary thermometry using a primary piston gauge
论文作者
论文摘要
为了达到单压折射率气体温度计（SPRIGT）0.25 MK的不确定性，在30 kPa至90 kPa的范围内，He-4气体的相对压力变化应不超过4 ppm（k = 1）。为此，已经开发了一种新型的压力控制系统。它由两个主要部分组成：用于控制压力的活塞量表，以及一个自制的气体补偿系统，以补充活塞量表的微薄表。此外，为了将活塞保持在恒定高度，使用一个伺服回路，该伺服回路会自动确定所需的额外气体量。在室温下，稳定压力的标准偏差为30 kPa的3.0 MPa，在60 kPa时为4.5 MPa，在90 kPa时为2 MPa。对于在本工作中用于Sprigt的温度区域5 K-25 K，相对压力稳定性优于0.16 ppm，即比要求的25倍。此外，相同的压力稳定系统很容易转座到其他原发性气体温度计。
To achieve an uncertainty of 0.25 mK in single-pressure refractive-index gas thermometry (SPRIGT), the relative pressure variation of He-4 gas in the range 30 kPa to 90 kPa, should not exceed 4 ppm (k=1). To this end, a novel pressure control system has been developed. It consists of two main parts: a piston gauge to control the pressure, and a home-made gas compensation system to supplement the micro-leak of the piston gauge. In addition, to maintain the piston at constant height, a servo loop is used that automatically determines in real time the amount of extra gas required. At room temperature, the standard deviations of the stabilized pressure are 3.0 mPa at 30 kPa, 4.5 mPa at 60 kPa and 2 mPa at 90 kPa. For the temperature region 5 K-25 K used for SPRIGT in the present work, the relative pressure stability is better than 0.16 ppm i.e. 25 times better than required. Moreover, the same pressure stabilization system is readily transposable to other primary gas thermometers.
