| dc.description.abstract | Due to the fact that the existing measuring techniques for physical properties nowadays mostly concentrate on single subject and constrain with specified environmental conditions. Furthermore, the cost of the equipment are usually expensive. This study aims to develop an innovative approach which features with relatively low set-up expense and could be adjusted flexibly to respond for different operating circumstances. On the basis of draining vessel method, this study eliminates the use of the theoretical formula and discharge coefficient instead, combining computational fluid dynamic(CFD) approach with multi-state regression procedure established by the results of sensitivity analysis to minimize the weighting mean square error between the mass flow rate of the experiment and those obtained by simulation to acquire the values of targeting properties. Take the pure water at 40℃ as representative of Newtonian fluid, measuring the corresponding density, viscosity and surface tension coefficient. The results show that compared with values quoted from literature, the density and the surface tension coefficient have the averaging error not more than 5%, besides, the latter demonstrate with better measuring stability. On the other hand, affected by the embedded difference between experiment and simulation, there is the averaging error of 15% of the results of the viscosity, and less than 10% for the best. We expand the application of such the approach to measure the viscous parameters of non-Newtonian fluid, and employ it to explore zero shear strain viscosity, infinite shear strain viscosity, time constant and power law index of the apparent viscosity of 0.1wt% xanthan gum aqueous solution at 30℃ under Carerau model. Fit the obtained parameters to the data attained by commercial equipment which obtain with the R2(coefficient of determination) being 0.9 in the mean, and 0.94 for the best. However, obvious differences could be observed between zero shear strain viscosity, infinite shear strain viscosity, time constant and power law index got by the designed approach and by direct regression, for the feasibility of the property-measuring technique proposed by this study to the non-Newtonian fluid, it still take further discussion and improvement in the near future. | en_US |