定容法液相pvT实验系统的研制及初步测试

Apparatus and Experiment for Liquid Phase pvT Measurement Using a Constant-Volume Cell

中文关键词: 液相pvT  定容法  R134a

英文关键词: liquid phase pvT  constant-volume cell  R134a

中文摘要:

      液相pvT是流体的重要热物理性质之一，定容法是一种可靠、精确的液相pvT测试方法。分析了定容法液相pvT的测量原理，并在此基础上研制了一套液相pvT实验系统，主要包括实验本体段、温度测量系统、压力测量系统、密度测量系统及真空系统，对可能影响实验测量精度的因素进行了细致分析，探索了液相pvT的实验流程。利用高纯度R134a标定了294.899 K、21.847 MPa 下的体积，研究了温度与压力对体积的影响，在此基础上开展了温度270 K~295 K，压力1.7 MPa~21.8 MPa下的R134a液相pvT实验，测量结果与文献结果吻合很好，验证了实验系统的可靠性和精度。

英文摘要:

      Liquid phase pvT behavior is an important thermodynamic property and can be measured precisely with a constant-volume cell. Based on the fundamental theory of the constant-volume method, a new apparatus for liquid phase pvT property measurement was built, including the constant-volume cell, the temperature measurement system, the pressure measurement system, the mass measurement system and the vacuum system. The volume of the constant-volume cell was calibrated with high purity R134a at temperature of 294.899 K and pressure of 21.847 MPa. Then the effect of temperature and pressure on the cell volume was analyzed. The pvT behavior of R134a in liquid phase was measured at temperature from 270 K to 295 K and pressure from 1.7 MPa to 21.8 MPa. The experimental results agree well with reference equation of state, the reliability of the apparatus is proved.