Experimental study on viscosities of TiO_2-H_2O nanofluids
Four different concentration TiO2-H2O nanofluids with 20 nm TiO2 were prepared with supersonic oscillator through appending hydrophilic dispersant into deionized water.The viscosities of TiO2-H2O nanofluids and deionized water were measured at different temperatures.The results showed that the viscosities of nanofluids increased apparently compared to the deionized water.And the viscosities varied inversely with the temperature of the TiO2-H2O mixture system.The results also demonstrated that the TiO2-H2O nanofluids were Newtonian fluids.
A method for predicting organic compound volatilization rates under turbulent liquid and gas conditions is developed. The reference compounds are classified according to their physico-chemical properties. The mass transfer coefficient (K(OL)) ratios for organic solutes to the reference compounds are constant for a wide range of environmental conditions, including liquid or air turbulence, or both at once. The obtained results indicate that when the environmental conditions are the same the determination of the volatilization rates is strongly dependent on the solute properties and the chemical structure. The presented method can more effectively estimate the volatilization rates of the solutes than the traditional one under various environmental conditions especially for low volatility solutes. The advantages and disadvantages of the traditional method are also discussed.