喷油压缩机用旋风式油气分离器筒体尺寸设计方法  

Design Method for Cylinder Dimension of Oil-gas Cyclone Separator Used in Oil-injected Compressor Units

作　　者：冯健美[1] 韩济泉 王旭忠 DANG Tiendat FENG Jian-mei;HAN Ji-quan;WANG Xu-zhong;DANG Tiendat(School of Energy and Power Engineering,Xi'an Jiaotong University,Xi'an 710049,China;Shandong Bin Yang Gasification Co.Ltd.,Binzhou 251800,China)

机构地区：[1]西安交通大学能源与动力工程学院,陕西西安710049 [2]山东滨化滨阳燃化有限公司,山东滨州251800

出　　处：《压缩机技术》2020年第3期1-8,共8页Compressor Technology

摘　　要：针对喷油压缩机系统用旋风式油气分离器筒体尺寸(直径和高度)设计基本依赖实际经验,缺乏理论依据的问题,提出了一种结合数值模拟的理论设计方法。通过理论计算可以得出设计分离器筒体直径的方法——依据切向速度关系曲线,通过选取合适的筒体直径而使外旋涡的平均切向速度大于临界切向速度。考虑到直筒形与筒锥形旋风分离器存在差异,借助数值模拟方法对理论计算的切向速度和有效分离高度进行了修正。建立了旋风式油气分离器的三维非稳态数值模型,其中气相流场采用RSM湍流模型,油滴运动轨迹采用离散相模型。计算了适用于额定工况下容积流量为6 m^3/min、排气压力为0.8 MPa(a)的空压机系统油气旋风分离器筒体尺寸,并计算分析了容积流量改变时(50%~100%)对分离器筒体尺寸的影响。最后经过数值模拟验证,结果表明所设计的分离器可对粒径为5μm以上的油滴完全分离。本方法适用于喷油压缩机系统中旋风式油气分离器的设计工作,也可以为其他场合应用旋风分离器作为设计指导。The determination of cylinder dimension(diameter and height)of the oil-gas cyclone separator used in the oil-injected compressor units relies mainly on practical engineering experience and lacks the theoretical basis.A theoretical design method combining the numerical simulation is proposed in this paper.The method of designing the diameter of cylinder that can be obtained on the basis of theoretical calculation is making the average tangential velocity of the outer vortex greater than the critical tangential velocity by selecting the appropriate cylinder diameter according to the curve of tangential velocity.Owing to the difference between the cylindrical and cylinder-on-cone cyclone,the theoretical calculation of the tangential velocity and the effective separation height were corrected by numerical simulation.The three dimensional unsteady numerical model is established where the gas flow field is simulated using the RSM turbulence model and the trajectory of the oil-droplets is traced by the discrete particle model(DPM).The calculation of the separator cylinder size was conducted and the analysis of the impact of the volume flow change(50%-100%)of compressor was made for an air compressor unit with the rated volume flow of 6 m3/min and exhaust pressure of 0.8 MPa(a).Finally,the numerical simulation results indicate that the designed separator can completely separate oil droplets with a particle size of 5μm or bigger.This method is applicable to the design of the oil-gas cyclone separator in the oil-injected compressor system,and can also be used as a design guide for other occasions.

关 键 词：喷油压缩机 旋风式油气分离器 筒体尺寸 切向速度 数值模拟 

分 类 号：TH455[机械工程—机械制造及自动化]