摘要
在石油输送工业中,由于弯头内压力梯度、离心力、二次流等多种因素的作用,导致弯头内的冲蚀过程特别复杂,冲蚀破坏也十分严重。本文针对液固两相流条件下颗粒对弯管的冲蚀破坏,采用DPM模型,对离散相在拉格朗日框架下求解颗粒轨道方程,得出颗粒与壁面的碰撞信息,再将碰撞信息应用于冲蚀模型,从而预测出颗粒对弯管壁面的冲蚀破坏情况,并研究了颗粒斯托克斯数对冲蚀严重区域的影响。计算结果表明:冲蚀主要发生在弯管与出口直管连接处的外拱壁以及靠近弯头出口的直管段侧壁区域;当颗粒斯托克斯数较大时,由于二次流对颗粒的携带作用不充分,导致靠近弯头出口的直管段侧壁区域未出现严重冲蚀。
As for such pipeline fittings as elbows in petroleum transportation systems,erosion is commonly encountered and leads to severely damage,the physical mechanism of which is extremely complex due to the multi effects of pressure gradient,centrifugal force and secondary flows inside them.In this paper a DPM(Discrete Particle Method) method with a Lagrangian scheme is employed to solve the particle trajectory equations of liquid-solid two-phase flow in elbows,and then a novel erosion model coupled with impingement characteristics among particle clusters extracted from the particle trajectory calculations is proposed to predict the wearing effect on the wall of elbows,in which the effect of the Stokes number of particles on predicting the severely worn regions are taken into account.The simulation results show that erosion occurs mainly on the extrados near the bend exit and the side walls of the downstream straight pipe close to the bend exit,while for high Stokes number no evident erosion arises on the side walls of the downstream straight pipe close to the bend exit due to the inadequate effect of the secondary flows on the particles.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2014年第4期691-694,共4页
Journal of Engineering Thermophysics
基金
国家高技术研究发展计划(863计划)课题(No.2012AA040105-01)
国家自然科学基金创新研究群体(No.51121092)