The purpose of this paper is to investigate the flow characteristics of local flow field in the vertical cylinder separator with inlet baffle at different curvature ratios (K). Computational fluid dynamics (CFD) was used to numerically calculate the three-dimensional turbulent flow for separators. The effect of K values was researched within the scope of -0.15—0.25 and baffles were classified into concave surface K>0,plate K=0 and convex surface K<0. The stagnation pressure and local resistance were calculated. Water was used as working fluid. The mechanism was analyzed at different K values about impinging jet in limited narrow space of separator inlet.The results showed that the impact on the baffle wall and the local flow resistance declines with the decrease of the curvature ratio K in the separator inlet. The average local resistance coefficient of K = -0.1 is 2.8％ lower than that of K=0,and K = 0.1 is 2.0％ higher. The local flow structures and the static pressure distribution were altered by different K. For the case of concave surface,jet expansion was limited in the impacted area due to the enlarging of jet exit-to-surface distance L. On the contrary,the convex surface was beneficial to the impinging jet expansion. Distribution of tangential velocity in wall jet region and baffle outlet was deeply affected by impacted area.%以立式圆筒体非均相分离器入口处的冲击挡板为研究对象,探究挡板的结构参数——相对曲率K对入口局域流体力学性能的影响.以水为介质,在K=-0.15～0.25范围内,利用计算流体力学三维湍流数值模拟,研究了凹柱面K>0、平面K=0和凸柱面K<0共3个类型的9种挡板结构入口局域流场的压力和阻力特性,分析了挡板结构对分离器入口受限空间冲击射流的影响机理.结果表明,随着相对曲率的降低,挡板所受冲击力下降,入口局域阻力下降.相对平挡板,K=-0.1的凸柱面挡板局域阻力相对降低2.8％,K=0.1的凹柱面挡板相对提高2.0％.在受限空间内,挡板相对曲率改变了射流冲击间距,影响了入口局域流场结构和静压力分布.凹柱面挡板有效地加长了冲击间距,限制了射流在冲击区轴向和径向扩展.而凸柱面挡板则缩短了冲击间距,有利于射流的扩展.射流冲击区对壁面射流区切向速度分布及挡板出口速度分布起到了决定性作用.
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