Fluoroketone C{sub}2F{sub}5C(O)CF(CF{sub}3){sub}2 as a Heat Transfer Fluid for Passive and Pumped 2-Phase Applications

摘要

C{sub}2F{sub}5C(O)CF(CF{sub}3){sub}2, a new Fluoroketone (FK) working fluid with an atmospheric boiling point of 49°C and Global Warming Potential (GWP) ～1, is proposed as an alternative to Perfluorocarbons (PFCs) and hydrofluorocarbons (HFCs) for passive and pumped 2-phase systems. Its thermophysical properties are very similar to those of the PFC C{sub}6F{sub}14. C{sub}2F{sub}5C(O)CF(CF{sub}3){sub}2 exhibits low acute toxicity and bears a recommended 8-hour exposure guideline of 150ppmv. Pool boiling experiments conducted with a porous metallic boiling enhancement at P{sub}(atm) showed h>8W/cm{sup}2-K at >30W/cm{sup}2. Metal corrosion and elastomer compatibility testing show the material to be very inert. 120 hour thermal stability tests conducted with C{sub}2F{sub}5C(O)CF(CF{sub}3){sub}2 at 230°C in sealed glass ampules with copper and aluminum coupons showed purity changes ～0.02%. It will hydrolyze in the presence of a separate water phase and the implications of this incompatibility for water-cooled systems require further investigation.