Study On Structure Optimization And Spray Characteristics Of Pressure-swirl Solid Nozzle

Single-side swirl nozzle is an important part in the seawater dueling device.Its spray characteristics directly affect the performance of the entire equipment.The poor spray uniformity leading to uneven heat transfer,not only affects the overall efficiency,but also affecting the lifespan of the equipment.Owing to its importance of the spray performance,it has always been research hotspots in related fields[1].Since the 1950 s,a large number of researchers have studied the nozzles from theory,experiments and numerical simulation.They summed up a lot of design theories and experience formulas,providing powerful support for the production and manufacture of nozzles.However,most of the work is concentrated on the theoretical derivation and structural design of the nozzle,and the nozzles are less optimized in specific areas.With the rapid development of the ANSYS and other platforms,they provide a few range of useful simulation optimization analysis tools to help researchers to work,which is very convenient.This article is optimized on the basis of solid nozzles,although the nozzle can form a solid spray effect,abide by the poor spray uniformity,there is a great improvement potential.Based on the Design Exploration module under the ANSYS platform,automatic optimization and analysis have been operated.Firstly,using UG to perform parameterization modeling,particularizing the nozzle 14 structural dimensions,and then executing a complete numerical simulation process in Fluid Flow(Fluent).Then setting up the variation range and optimized target variables in Direct Optimization.After setting up the parameters,the optimized program can be performed,and the best structural parameters will be calculated.In Parameter Correlation,which parameters can be analyzed,it will focus on the impact of this structure,and provide the most favorable support for subsequent improvements.This optimal optimization has increased 11.9% relative to the prototype nozzle′s uniformity finally,and we found that the diameter of the nozzle direct pipe section has the greatest impact on the spray uniformity,which reduces the spray uniformity with the parameter increasing.After comparing the speed and energy contour of different straight pipe segments,the reduction of the radius increases the speed difference between the discharged water flow and the upward air,which directly helping the liquid cracking into a liquid band,as well as the liquid band breaking into small droplets.According to the analysis,the tremendous speed difference is advantageous for the formation of small droplets,as well as the distribution of droplets in the spatial plane,and it can improve the uniformity.In order to measure the uniformity before and after the optimization,four evaluation methods have been taken respectively,the union of the area-weighted average and massweighted average,the circumferential mass flow uniformity formula,the radial mass flow uniformity formula and the centroid and shape vector evaluation method for makeup.After contrasting,it was found that there was no improvement in the circumferential uniformity,but the other three were significantly improved,which providing the theoretical guidance for the subsequent improvement.