高压下声速温度系数的一种新算法

A METHOD TO ESTIMATE TEMPERATURE COEFFICIENT OF SOUND VELOCITY AT HIGH PRESSURE

从声速的定义出发 ,由热力学基本关系给出了声速温度系数 (偏微商 )的一种计算方法 ,以顽火辉石为例 ,计算结果显示 ,在 4 0～ 140GPa压力范围内 ,其纵波、剪切波和体波的温度系数随压力的增大而逐渐减小 ,分别由 4 0GPa时的 - 0 386、- 0 2 51、- 0 2 55m (s·K)降至 80GPa时的- 0 2 98、- 0 188、- 0 2 0 4m (s·K) ,12 0GPa时的 - 0 2 4 4、- 0 148、- 0 175m (s·K)和 140GPa时的- 0 197、- 0 131、- 0 162m (s·K)。将这一规律内推至零压得到 ( K/ T) 0 =- 0 0 2 79GPa·K-1,与静高压下的实验值吻合很好。

A method to calculate the temperature coefficients of sound velocity at high pressure were given,in terms of the definition of sound velocity and thermodynamics.For perovskite enstatite,the calculated temperature coefficients of compressional,shear and bulk wave velocities decease from 0 386,0 251,0 255m/(s·K) at 40GPa to 0 298,0 188,0 204m/(s·K) at 80GPa,0 244,0 148,0 175m/(s·K) at 120GPa and 0 197,0 131,0 162m/(s·K) at 140GPa,respectively.Extrapolating these to zero pressure gives ( K / T ) 0=-0 0279GPa·K -1 ,which is consistent well with the value from hydrostatic experiment. [WT5HZ]