Heat Transfer Model for Liquid-Liquid Taylor Flow in Mini-Scale Coiled Tubing

Abstract

In this paper, an experimental study on heat transfer enhancement using non-boiling liquid-liquid Taylor flow in mini scale coiled tubing for constant wall temperature conditions is conducted. Coiled copper tubing with different radii of curvature and lengths were used as test sections. Segmented slug flow with water and three low viscosity silicone oils (1 cSt, 3 cSt, 5 cSt) were used to examine the effect of Prandtl number on heat transfer rates in coiled tubing. Additionally, benchmark tests were conducted of single-phase flow in a straight tube. The experimental results are compared with models for liquid-liquid Taylor flow in straight and coiled tubing. This research provides new insights on the enhanced heat transfer rates attainable with using liquid-liquid Taylor flow in mini scale coiled tubing. This enhancement occurs due to internal circulation and secondary flow in the fluid segments.