Study On The Uniformity Of Temperature Distribution On The Liquid-liquid Impinging Surface

The impact flow is that the interphase transfer coefficient can be greatly improved by collating two or more in-phase or non-cophase fluids and finally producing a strong turbulent region in a certain region,which can realize the rapid and efficient micro-mixing of the two-phase fluid.Impact flow is a particularly efficient way to achieve local heat and mass transfer.There are many applications of non-isothermal fluid collision in energy,chemical and other fields.In this paper,the temperature distribution uniformity of the mixed impact surface formed by the non-isothermal liquid-liquid alignment impact under different conditions is studied.The temperature inhomogeneity coefficient and impact surface temperature distribution were used as the evaluation criteria.The Mixture model was used to simulate the impact process numerically,and the model was verified by visual measurement experiments based on planar laser induced fluorescence(PLIF)technology.The temperature distribution of impact surface under the two collision modes of center impact and eccentric impact is studied under different velocity(v),nozzle spacing(L),and turbulent kinetic energy.The results show that the law of temperature distribution uniformity of the impact surface is approximately the same in the two modes of center impact and eccentric impact.When the nozzle diameter and the nozzle alignment distance are fixed,the temperature inhomogeneity coefficient decreases as a whole,and when the nozzle diameter and nozzle exit velocity are fixed,the temperature field distribution of the forming area after the non-isothermal liquid-liquid alignment impact increases with the nozzle spacing,and the temperature distribution interval decreases.When L=3 D,the distribution interval of temperature is the smallest and the distribution of temperature field is the most uniform.The more stable the turbulent kinetic energy distribution curve,the more uniform the temperature distribution of the gas-liquid mixed impact surface formed after the liquid-liquid collision.In order to study the influence characteristics of each parameter,the combination of numerical simulation and experimental verification is adopted,and the mixing uniformity of impact surface is optimized based on orthogonal test method.First,the single factor analysis method is used to study the impact process of nozzle diameter,nozzle spacing,nozzle outlet flow rate and liquid solubility at different outlet temperatures.The temperature inhomogeneity coefficient is used to judge the uniformity of the temperature distribution of the impact surface,and the influence characteristics of each single factor are obtained.Then by designing the orthogonal experiment of four factors and three levels,the structure and operation parameters are optimized synthetically by range analysis,and the influence degree of each parameter and the optimal level combination of each parameter are obtained.The results show that the temperature inhomogeneity coefficient decreases first and then increases with the increase of nozzle diameter,nozzle outlet flow rate,nozzle spacing.The temperature distribution uniformity of the impact surface is better after the two strands of liquid are collocated,and the influence degree on the temperature inhomogeneity coefficient of the mixing surface is from strong to weak: nozzle diameter,liquid mutual solubility,flow rate,nozzle spacing.the optimal combination of the parameters is as follows: nozzle diameter is 8 mm,nozzle outlet flow rate is 1100 L·h-1,nozzle spacing is 24 mm,two nozzles are mutually soluble 350 K water and 310 k ethanol,respectively.