论文部分内容阅读
理论上求解了高黏度流体表面波的色散方程,发现此类表面波随无量纲数Y值增大,存在一极值点Y≈0.145,跨越该点时表面波的弛豫特征由指数衰减转变为振荡衰减,同时流体表面波的色散方程也发生根本变化。为了验证上述推论的正确性,利用表面光散射法研究了温度在286.27~373.32K范围内时高黏度流体邻苯二甲酸二异癸酯(DIDP)的弛豫特征和黏-温特性。结果表明:Y值随温度升高而减小,当Y<0.145时,表面波以指数形式衰减且不传播,此时黏度测量值与文献值的平均偏差不超过±1.5%;当Y>0.145时,表面波以振荡衰减形式传播,此时黏度测量值与文献值的平均偏差不超过±2%;当Y→0.145时,黏度测量偏差急剧增大,不能可靠地获得流体黏度。研究结果有助于认识高黏度流体表面波的弛豫特征,为利用表面光散射法精确、可靠地测量高黏度流体黏度奠定了基础。
The dispersion equation of high-viscosity fluid surface wave is theoretically solved. It is found that with the increase of dimensionless number Y, there exists an extreme point Y≈0.145, and the relaxation characteristic of surface wave transits from exponential decay For the oscillation attenuation, while the fluid surface wave dispersion equation also undergo a fundamental change. In order to verify the correctness of the above inference, the relaxation characteristics and viscosity-temperature characteristics of high viscosity fluid diisodecyl phthalate (DIDP) were studied by surface light scattering at a temperature range of 286.27 ~ 373.32K. The results show that the Y value decreases with the increase of temperature. When Y <0.145, the surface wave attenuates exponentially and does not propagate. The average deviation of the measured value from the literature value does not exceed ± 1.5%. When Y> 0.145 , The surface wave propagates in the form of oscillatory attenuation. At this time, the mean deviation of the measured value from the reference value does not exceed ± 2%. When Y → 0.145, the deviation of the viscosity measurement sharply increases and the viscosity of the fluid can not be reliably obtained. The results are helpful to understand the relaxation characteristics of high viscosity fluid surface wave and lay the foundation for the accurate and reliable measurement of viscosity of high viscosity fluid by surface light scattering.