Systematic extension of a force field for fluorinated propenes to HCFO and longer-chained HFO compounds, and its application for studies on new working fluids

该项目的目的是将氟化丙烯的力场系统地扩展到基于氟化丁烯的氢氯氟烯烃（HCFO）和氢氟烯烃（HFO）。因此，它的重点是调查的Lennard-Jones（LJ）参数的氟和氯原子的可转移性，以获得一组一致的LJ参数，使研究不同的HFO/HCFO化合物与任何数量的键合卤素原子。此外，在氟化丁烯中围绕二面角的旋转导致复杂的扭转分布。这需要详细分析可能的函数形式，以重现扭转轮廓，其对液体粘度的模拟研究的影响。这种分析还必须在扭转参数的可传递性方面进行。研究将在不同的HCFO化合物和氟化丁烯的基础上进行，这些化合物目前被提议作为各种应用的新工作流体。扩展力场将用于纯化合物和不同二元混合物的汽液相平衡和液相密度和粘度的分子模拟研究。合作伙伴将使用分子模拟结果来开发这些系统的状态方程（EOS）模型。然后，EOS模型将用于选定的二元混合物的热系统的系统模拟研究，以说明使用分子模拟的信息来评估新的工作流体。

The aim of this project is the systematic extension of a force field for fluorinated propenes to hydrochlorofluoroolefines (HCFO) and hydrofluoroolefines (HFO) based on fluorinated butenes. It thereby emphasis on investigating the transferability of the Lennard-Jones (LJ) parameters for fluorine and chlorine atoms to derive a consistent set of LJ parameters that enables studies on different HFO/HCFO compounds with any number of bonded halogen atoms. Furthermore, the rotations about dihedrals in fluorinated butenes result in complex torsion profiles. This requires a detailed analysis on possible functional forms to reproduce the torsion profiles, and its influence on simulation studies on liquid viscosities. This analysis has also to be performed with regard to the transferability of the torsion parameters.The studies will be carried out on the basis of different HCFO compounds and fluorinated butenes that are currently proposed as new working fluids for various applications. The extended force field will then be employed for molecular simulation studies on the vapor-liquid phase equilibria and liquid phase densities and viscosities of the pure compounds and different binary mixtures. The molecular simulation results will be used by cooperation partner to develop equation of state (EOS) models for these systems. The EOS models will then be employed in system simulation studies on thermal systems for selected binary mixtures to illustrate the use of information from molecular simulations to evaluate new working fluids.