Experimental Research On Atomization Characteristics Of Pressure Nozzle And Numerical Simulation On Heat And Mass Transfer In Spray-Dryer

Experimental equipment had been established to research atomization characteristics of a type of pressure nozzle. The hole diameters of nozzle were 0.8mm, 1.2mm and 1.6mm. Glycerol-water solution was used for working fluid. The atomization pressure varied from 0.5MPa to 7.0MPa. We got these characteristics, such as atomization angle, droplet SMD and flux in the radial direction, which were acted by atomization pressure, nozzle diameter and viscosity of solution. The results indicate that, atomization pressure and nozzle hole diameter have a remarkable influence on the atomization characteristics. The distribution of spray cone is solid,and the larger pressure, the more distinct. The flow coefficient has no relation to pressure, but the nozzle hole diameter. The simple test method can meet the needs of analyses. Experimental result can supply reference with this type of pressure type nuzzle in engineering practice.To study the flow fields, and the heat and mass transfer in spray dryer, the differential equations of transfer had been established. The k-εturbulence equations were used to simulate gas phase flow field in spray drying process, and the particle trajectory model described droplet movement trajectory. To consider the interaction between the gas phase and the particles, the source items were introduced to the differential equation. The SIMPLE algorithm was used to calculate the gas phase flow equations, and PSI-cell algorithm calculated coupling action. We gained the issues, such as gas phase velocity, temperature and moisture content distribution,...