Experimental Investigation and Empirical Models of Viscosity of Trifluoroidomethane (CF 3 I)

In this research, the primary emphasis is placed on conducting experimental viscosity measurements of CF 3 I and subsequently developing empirical models using the obtained data to facilitate engineering system design calculations. Recognized for its non-explosive, low toxicity characteristics, and negligible contributions to ozone depletion and global warming, CF 3 I is identified as a promising candidate of a component for next-generation refrigerant mixtures. This potential arises from its advantageous thermodynamic properties, including a low boiling point and high critical temperature, making it a noteworthy component in refrigerant mixtures. The research employs the tandem capillary tube method to measure the viscosity of CF 3 I in both liquid and vapor phases. This approach, involving the series arrangement of two capillary tubes, is designed to neutralize the effects of the tubes, facilitating accurate viscosity measurement. Experimental data were collected at temperatures between 333 K and 374 K for the liquid phase and 333 K to 394 K for the vapor phase, under pressures ranging from 1.0 MPa to 4.0 MPa. Expanded uncertainties associated with these measurements were 2.22 % and 2.32 % for the liquid and vapor phases, respectively. Furthermore, the collected data were used to develop viscosity models for CF 3 I using the Extended Corresponding States and the modified Residual Entropy Scaling methods, effectively encapsulating the experimental findings within the calculated uncertainty limits. These models will also be useful for predicting the viscosity of any mixture refrigerant where CF 3 I is a constituent component.