摘要
采用三维软件对4DB柴油机螺旋进气道的流动特性进行数值模拟,将计算得到的流量系数、涡流比与试验值进行对比,以此验证了模型的准确性。通过对进气道模型对关键流道截面的速度场与湍动能场的分布规律、进气道螺旋段气流流线局部剖视图进行深入分析,得出影响螺旋进气道流动性能的关键制约因素。结果表明,在进气门背面靠近气道入口一侧区域存在显著的气流涡旋,导致该处湍流耗散作用较为严重,引起较高的流动损失。局部涡旋的产生是造成该区域湍动能较高且气流流速降低的主要原因。
The fl ow characteristics of the helical air intake of 4DB diesel engine were numerically simulated by using 3D software. The fl ow coeffi cient and the swirl ratio obtained from simulation were contrasted with the test data, so as to verify the accuracy of the model. After analyzing the distribution law of velocity fi eld and turbulent kinetic energy fi eld of the section of key fl ow passages in the air inlet model as well as the partial section view of the air fl ow line in the helical segment of the air intake, the paper obtained the key factors restricting the fl ow performance of the helical air intake. The results showed there was obvious fl ow vortex near the entrance side of the port at the back of the air intake, which led to serious turbulent dissipation and high fl ow loss. Local vortex was the main cause of high turbulent kinetic energy and reduced air fl ow velocity.
出处
《矿山机械》
2016年第4期74-78,共5页
Mining & Processing Equipment
关键词
柴油机
进气道
速度场
湍动能
diesel engine
air intake
velocity fi eld
turbulent kinetic energy
