超临界CO_2热力学性质的理论计算

Theoretic calculation on thermodynamic character for SCF CO_2

应用BWR方程在温度为310～600K、压强为75～300bar范围内拟合的超临界CO2流体状态方程,计算了超临界状态下CO2体系的熵、热容和焓。研究表明,这些热力学函数具有明显的超临界特性;与文献值相比,超临界状态下CO2熵的相对误差小于0.4%,而定压热容的相对误差稍大,为2.45%(T:330～360K),其数据为进一步从理论上研究超临界CO2与金属铀表面反应的热力学行为奠定了基础。

The entropy, thermal capacity and enthalpy under supercritical fluid were calculated by means of the supercritical fluid CO_2 state equation refined with BWR equation at 310～600 K and 75～300 bar. It was demonstrated that these thermodynamics functions have obvious supercritical fluid character, In comparison with literature results, the relative error of the entropy was lower than 0.4%, but relative error of the thermal capacity was 2.45%(T:330～360 K), and moreover these results contributed to the theoretical research of the surface reactions between supercritical fluid CO_2 and metal uranium.