Numerical Simulation Based Shape Optimization Analysis Of Tooth Pier Inner Dissipator

Tooth pier inner dissipator is the proposed form of energy dissipation,compared with the traditional form of energy dissipation,which is to solve the shortage problem of the poor flow ability, and ensure the energy dissipation at same time,it is a kind of potential inner energy dissipator, the research significance is very significant. In the early,there have been in the form of internal energy dissipation physical model test research was conducted on the hydraulic characteristics, analysed the teeth number of the pier and area contraction ratio on the properties and the effect of energy dissipation and pressure in this paper, based on this, using the current widely used turbulent numerical simulation software package, Fluent software to carry on the numerical simulation research, study the different dental height and flow area on dental shape head loss coefficient of the kinetic energy dissipation,energy dissipation,the section stress distribution and the distribution of the velocity vector of the clouds. The main research contents and conclusions of this paper are as follows:1.Through the analysis of the pressure characteristics of the different shape of the tooth pier type,we can find the mean pressure in the pipeline variation along the way is similar,which is that it remains stable in tooth pier before pipeline,decreases rapidly in parts of the tooth block layout,and then gradually increased until steady state recovery.2.The velocity vectors variation of each type of the tooth pier type inner energy dissipator can be roughly the same, and the velocity of the upstream and downstream of the channel which is farther from the tooth pier segment is basically rectangular in uniform distribution. Near the pier section, The flow velocity near the wall is relatively small, and the position of the central axis of the pipe and the range of the upper and lower 0.3D show the maximum and the same velocity value. Accompanied by the decrease of area reduction ratio, the reverse flow is enhanced, and the velocity recovery length is also growing.As the area contraction ratio remains unchanged,with the increase of the height of the tooth pier,the range of reverse flow velocity is basically unchanged after the section of the pier, and the change of length of the velocity recovery zone is not very obvious,keeping around 1.3D,so the effect of the height of the tooth on the velocity distribution is not very obvious.3.The turbulent dynamic kinetic energy and turbulent energy dissipation rate distribution of the different shape of tooth block type energy dissipation are roughly the same,their maximum value appears in the vicinity of the tooth pier entrance location,and the turbulence is also the most fiercely. After flowing through the tooth pier section, the turbulent kinetic energy and turbulent dissipation rate continue to decay until a full recovery along the direction of flow tube length growth.As the area contraction ratio decreases, the value of the turbulent kinetic energy and turbulent kinetic energy dissipation rate also increases accordingly. Under the the same area contraction ratio,the degree of turbulence changes slightly with the increase of tooth height,but the volatility is not big,that is to say, the overall stability is in the same range.4.It is concluded that the head loss is mainly due to the local head loss caused by sudden contraction and sudden expansion,When the shape of the tooth pier type is determined, the approximate level of head loss line is similar, the difference of head loss coefficient is similar, and the change of the flow rate is not changed.The local head loss coefficient increases with the decrease of the area contraction ratio, and the energy dissipation effect is also increased obviously. When the area contraction ratio is certain, the local head loss coefficient is between 3.7 and 3.8, and the energy dissipation effect is not quite different.5.When the tooth shape of pier is determined, pier type energy dissipater with flow rate increases;the same flow with area contraction ratio decreases, eliminate energy more and more, amplitude increases also with the increase of the flow rate increases,.Tooth pier height changes, the flow of the corresponding energy dissipation is almost the same, that tooth height of pier on energy dissipation rate is slightly affected, but the impact is not great.6.The main reason of influencing the water flow characteristics of Tooth pier inner dissipator is the over current area, which has a little effect on the change of the height of the height of the pier.