FLOW RESISTANCE AND HEAT TRANSFER REDUCTION BEHAVIOR OF ORGANIC BRINE IN THE COLD HEAT TRANSPORTATION SYSTEM BY ADDING DRAG REDUCTION SURFACTANT

摘要

There has been some interest in the flow resistance and heat transfer reduction effects of some brine flow with drag reduction additives in order to make on effective heat energy transportation system practicable. Therefore, the flow drag and forced convection heat transfer characteristics of organic brine flow (Ethylene Glycol (EG) solution) with drag reducing surfactant (Oleyldihydroxyetyl Amine Oxide (ODEAO) of non-ion surfactant) have been investigated. The main parameters in the present study were the concentration of EG (0 to 50 mass %), the concentration of ODEAO (about 2500 to 9000ppm) and temperature of the EG brine with ODEAO (-20 to 15°C). It is found that the flow friction and heat transfer coefficients of EG brine with ODEAO are dramatically lower than those of water or the EG brine. This flow drag and heat transfer reduction effect was caused by the surfactant's rod-like micelles aggregation, which was broken up by a high wall shear stress. The Reynolds number range for the flow drag and heat transfer reduction of the EG brine with ODEAO was wider as compared with the ODEAO water solution. Also, it was found that the surfactant's rod-like micelles aggregation was reinforced by a polar-nonpolar solubilization between the ODEAO's rod-like micelles and the EG molecules. Finally, Useful non-dimensional correlative equations (flow resistance, heat transfer and Reynolds number) for maximum flow drag and heat transfer reduction effect are derived in terms of various non-dimensional parameters.