Measurements of isobaric heat capacities for HFE-7000 and HFE-7100 at different temperatures and pressures

• A new flow calorimeter was used, which was assessed by measuring the heat capacity of ethanol.
• The heat capacity of HFE-7000 and HFE-7100 were reported at different conditions.
• The Garg type equation was used to correlate the data.
• The applied correlation satisfactorily represented the data.

This paper presents the heat capacities of HFE-7000 and HFE-7100 by a flow calorimeter. Ethanol has been used as a reference fluid to validate the flow calorimeter at different pressures and temperatures. With the flow calorimeter, the isobaric heat capacity of HFE-7000 (1-methoxyheptafluoropropane) and HFE-7100 (methoxy-nonafluorobutane) were measured in the temperature range from (255–294) K and from (255–323) K, respectively, and pressures up to 15 MPa. Through measuring the heat capacity of ethanol, the combined expanded uncertainty with a level of confidence of 0.95 (k = 2) of the measurement was estimated to less than ± 2%. The measured heat capacity values of HFE-7000 and HFE-7100 were correlated by the Garg equation. The calculated values showed good agreement with the experimental values.