【摘要】 流体中携带的固体颗粒对弯头等部件产生极大的损伤。大多数研究都集中在单个弯头的冲蚀,而串联弯头的冲蚀行为更为复杂。为此建立一个串联双弯头CFD(computational fluid dynamics)数值模型,利用该模型研究颗粒直径、流速、弯头之间的连接长度以及曲率半径对两个串联弯头冲蚀行为的影响。结果表明:弯头1的冲蚀行为与单个弯头的情况类似;大尺寸颗粒在弯头1处造成的冲蚀更严重,在弯头2处造成的冲蚀反而较小;当气体速度较低时,颗粒二次碰撞无法造成较大的冲蚀损伤,V形冲蚀形貌并不明显;随着连接管长度增加,有更多颗粒以滑动摩擦方式通过弯头2,弯头2的冲蚀速率会随之降低;随着曲率半径增大,V形冲蚀形貌逐渐演变为闭合环。更多还原

【Abstract】 The solid particles carried in the fluid cause great damage to the parts such as elbow. Most studies focus on the erosion of a single elbow, but the erosion behavior of elbows mounted in series is more complicated. Therefore, a computational fluid dynamics(CFD) numerical model of two elbows mounted in series was established. The influence of particle diameter, flow velocity, connection length between elbows and curvature radius on the erosion behaviors of two elbows mounted in series was studied by the established numerical model. The results show that the erosion behavior of elbow 1 is similar to that of a single elbow. Large sized particles cause greater damage at elbow 1, and less erosion at elbows 2. When the gas velocity is low, the secondary collision of particles cannot cause greater erosion damage, and the V-shaped erosion morphology is not obvious. With the increase of the length of the connection pipe, more particles can pass through elbow 2 by sliding friction, so the erosion rate of elbow 2 decreases. As the curvature radius increases, the V-shaped erosion morphology gradually evolves into a closed ring.更多还原