二氧化碳在RP-3航空燃油中扩散系数实验

基于压力降落法原理，搭建扩散系数测试实验装置，测试了29815K时CO2在水中的扩散系数并与文献值比较，验证了实验系统的可靠性。实验测定了密闭容器中28315～33315K时CO2 RP 3燃油体系中的压力随时间的变化值。实验测量曲线与数值拟合曲线完全稳合，计算得出不同温度下气体在燃油中的扩散系数值为10-8m2/s数量级。由实验结果可知:气体扩散系数与温度之间符合化学反应阿伦尼乌斯定律，由此根据已有扩散系数值可建立CO2在RP 3燃油中扩散系数预测模型。采用25315、26315K和27315K时3组实验数据来验证模型的准确性，结果显示实验数据符合预测模型方程，模型具有一定的外延性。 

Experiment on diffusion coefficient of carbon dioxide in RP-3 aviation fuel

A experiment apparatus based on the pressure decltion method was constructed, and the preliminary results concerning the carbon dioxide Water diffusion system at 29815K were in reasonable agreement with other report. Then it was used to measure the gas pressure versus time for carbon dioxide RP 3 aviation fuel system under a temperature range from 28315K to 333.15K. The fitting curve agreed with the experimental data perfectly, the diffusion coefficient values at different temperatures were of magnititude 10-8m2/s. From the experimental result, the relationship between the mass diffusion coefficient and temperature satisfied the Arrhenius rate law. A model of prediction of diffusion coefficient of carbon dioxide in RP 3 aviation fuel was built according to existing data in the experiment. To verify the accuracy of the prediction model, more experiments under the conditions of 253.15, 263.15K and 273.15K were conducted. The experiment results matched the fitting equation with accuracy and extensionality.