准直管磨料射流喷头内流的数值模拟

基于多相流动的拉格朗日离散相模型，应用FLUENT软件对准直管磨料射流准直管静止不动、入口带圆锥收敛段的直管磨料喷头内部等温、不可压缩、稳态、液固湍流进行了数值模拟.连续相采用三维不可压缩稳态雷诺时均N-S方程，湍流模型采用标准的k-ε模型，代数方程组采用分离解方法，通过SIMPLE算法求解压力速度耦合；离散相采用拉格朗日方法追踪颗粒运动轨迹；收敛残差为10^-4.研究表明，喷头混合室内存在2个环形回流区，室内连续相呈非轴对称流动.当准直管磨料射流用于切割工作时，磨料入口应略靠近混合室的出口侧；用于超细粉碎工作时，磨料入口应略靠近混合室入口侧.

Numerical simulation of the nozzle inside-flow of collimated pipe abrasive water jet

Based on the Lagrange discrete phase model of muhiphase flow, a numerical simulation was conducted for isothermal, incompressible, steady state, solid-liquid turbulent flow through straight pipe abrasive nozzle with collimated pipe hold still and cone convergent section at inlet used in collimated pipe abrasive water jet with FLUENT software. Three dimensional incompressible steady state Reynolds time-averaged N -S equations was used in the continuous phase, and the standard k -8 model was used in turbulence model. And the segregated solution method was applied in the algebraic equation groups. The pressure-velocity coupling was solved though the SIMPLE method. The Lagrange method approach was used to trace the particle movements in dispersed phase. And the convergence criteria is 10^-4. The study indicates that there are two annular circumfluence areas in nozzle mix room. The continuous phase shows non-axis symmetry flow in room. When collimated pipe abrasive water jet is used to cutting work, abrasive inlet should close with outlet side of mix room a little; when collimated pipe abrasive water jet is used to superfine grinding work, abrasive inlet should close with inlet side of mix room a little.