Experimental study on rheological and thermophysical properties of seawater with surfactant additive – Part II: Surface tension and thermal conductivity

This paper follows Part I of the rheological and thermophysical propertires of seawater with surfactant. In Part II, the thermophysical properties of seawater with the addition of different amounts of CTAC/NaSal are measured at different temperatures, including surface tension and thermal conductivity. Uncertainty analyses are conducted for all the measurements. The effects of the temperature, the salts in the seawater and the concentration of CTAC/NaSal on the thermophysical properties are investigated, and the corresponding influence mechanisms are analyzed. The results show that the addition of salt can decrease the surface tensions of the CTAC/NaSal solutions prepared by deionized water, and the surface tension of seawater is dramatically reduced after the addition of CTAC/NaSal. There is no substantial difference in the thermal conductivity among the solutions with different CTAC/NaSal concentrations at each temperature. Tap water can be utilized instead of deionized water in the following experiments on RSCE as expected.