Volume 34, Issue 3 (May 2006)
Hot Wire Method to Characterize the Thermal Conductivity of Particle-Filled Polymer Grouts Used in Pipe-in-Pipe Application
Insulated flowlines are considered a practical solution to prevent hydrate formation and paraffin deposition during the transportation of unprocessed well fluids to production facilities. A conventional pipe-in-pipe (PIP) system relies mainly on the heat transfer mode based on the thermal conductivity of the insulation material. Hence, in this study, a laboratory procedure was used to determine the thermal conductivity (k) of a polymer-based insulator (pumpable before setting) with and without filler materials. Microspheres (<0.008 in. (0.2 mm)) and aggregates (<0.752 in. (19.1 mm)) were used as filler materials. The conventional radial-flow hot wire method was compared with the axial-flow hot wire method to determine the thermal conductivity. Both transient and steady state conditions were used to determine the thermal conductivity of polymer composites. The thermal conductivity of the polymer at steady state was 0.107 W/mk, which was reduced due to the addition of microspheres and was increased due to the addition of aggregates. The thermal conductivity of pure polymer at steady state was 14.5 % higher than the transient thermal conductivity. Based on published data, a relationship between thermal conductivity and density was developed and verified with data from the current study.