Homogeneous Nucleation Investigation

本研究将开发一种高压扩散云室，用于测量适度过饱和下的成核速率。该腔室将设计在高达10,000 K Pa的压力和高达600 K的温度下运行，大大扩展了迄今为止可用的范围。因此，某些物质在其临界点附近的成核动力学是可以测量的。操作理论将扩展到考虑非理想情况、蒸汽损耗和潜热释放。将测量乙醇和壬烷的成核动力学作为温度和压力的函数。成核是环境和工程应用中的一种重要现象。动力学对温度、过饱和和材料性质极为敏感。预期的数据应该有助于选择改进的成核理论。

This research will develop a high pressure diffusion cloud chamber for measurement of nucleation rates at modest supersaturation. The chamber will be designed to operate at pressures up to 10,000 K Pa and temperatures up to 600 K greatly expanding the range heretofore available. Thus nucleation kinetics will be measurable for some substances near their critical points. The theory of operation will be expanded to account for non-idealities, vapor depletion, and latent heat release. Nucleation kinetics will be measured for ethanol and nonane as functions of temperature and pressure. Nucleation is an important phenomena in the environment and in engineering applications. The kinetics are extremely sensitive to temperature, supersaturation, and material properties. The expected data should help in the selection of improved theories for nucleation.