混空轻烃燃气气体分布器数值模拟及结构优化

Numerical simulation investigation on structure optimization of distributor in mixed-air light hydrocarbon gas vaporizer

混空轻烃燃气发生装置的工作原理是向装有液态轻烃燃料的储罐内鼓入空气,液态轻烃蒸发附着在空气泡表面形成混空燃气,其中气体分布器对轻烃气化过程起着决定性的作用,是气化装置内的核心部件。建立轻烃气化装置分布器的三维数值模型,模拟分布器内气液两相流过程,并针对现有气体分布器结构存在的缺陷提出相应的优化方案,分别对分布器支管尺寸、周向开孔、轴向开孔间距及开孔尺寸进行了优化。研究结果表明:周向开孔存在气体分布不均匀及液体回流,轴向开孔间距为50 mm时,汽化器空间利用率最高;开孔尺寸为10 mm时气液接触面积最大,最利于轻烃的气化。本次研究结果为混空轻烃燃气发生装置中气体分布器的优化设计提供了重要参考。

The working principle of the mixed air light hydrocarbon gas vaporizer is to blow air into the storage tank containing liquid light hydrocarbon fuel.The evaporated liquid light hydrocarbon is attached to the surface of the air bubble,and then a mixed gas is obtained.The gas distributor in mixed-air light hydrocarbon gas vaporizer,which is the core component in the gas generator,plays a decisive role in the light hydrocarbon gasification process.A three-dimensional numerical model of the existing light hydrocarbon vaporizeris established and the gas-liquid two-phase flow process in the distributor was numerically simulated.A corresponding structural optimization scheme was proposed based on the defects of the existing gas distributor.The size of branch pipe,circumferential opening,axial opening spacing and opening size were optimized.The results of the study show that gas distribution is uneven and there will be liquid backflow in the circumferential opening.Vaporizer space utilization is the highest when the axial opening spacing is 50 mm.The gas-liquid contact area is the largest when the opening size is 10 mm,which is most conducive to the gasification of light hydrocarbons.The results of this study provide an important reference for the optimal design of the gas distributor in the light hydrocarbon vaporizer.