齿墩内表面不同的两种体型齿墩式内消能工的数值模拟

为了研究两种体型齿墩式内消能工对管道内部水力特性的影响,采用FLUENT软件中的κ-ε数学模型模拟分析了齿墩内表面为平面(体型Ⅰ)和齿墩内表面为圆曲面(体型Ⅱ)两种体型消能工的流场、压力场、紊动能及水力参数等。结果表明,相同流速下齿墩内表面由曲面变为平面会扩大压强变化段长度和减小消能工出口处低压区的压强,且在大流速时体型Ⅰ在该区出现负压;消能工出口管壁附近会出现漩涡区,齿墩内表面由平面变为曲面,旋涡区域减小;紊动能的突变区域出现在消能工出口后,齿墩内表面由平面变为曲面会减小该区域的紊动能及其范围;齿墩内表面由平面变为曲面,消能工的消能率减小,流量系数加大,与其水力半径密切相关,为齿墩式内消能工的体型优化提供了依据。

Numerical Simulation of Two Body-type of Toothed Internal Energy Dissipators with Different Tooth Pier's Inner Surface

In order to study the impact of two-type of toothed internal energy dissipator on the hydraulic characteristics of the pipeline,the flow field,pressure field,turbulent kinetic energy and hydraulic parameters of two body-type of the energy dissipator,which the tooth pier of them are body-type Ⅰ(the inner surface of the tooth pier is flat)and body-type Ⅱ(the inner surface of the tooth pier is a curved),are studied by theκ-εmathematical model in FLUENT software.The results show that changing the inner surface of the pier from a curved surface to a flat surface at the same flow rate will increase the length of the pressure change section and reduce the pressure of the low pressure area in the outlet of energy dissipator,and negative pressure appears in this area at a high flow rate for the scheme with the body-typeⅠ.A vortex area appears near the outlet wall of the energy dissipator,and the vortex area will decrease when the inner surface of the tooth pier changes from a flat surface to a curved surface.The abrupt region of turbulent kinetic energy appears after the outlet of energy dissipator,and the area of turbulent kinetic energy and its range reduce when the internal surface of the tooth pier changes from a flat surface to a curved surface.When the inner surface of the tooth pier changes from a flat surface to a curved surface,the energy dissipation rate of energy dissipator decreases while the discharge coefficient increases,which are closely related to its hydraulic radius.It provides the basis for the body shape optimization of toothed internal energy dissipator.