Numerical Simulation On Influence Of Flow Characteristics For The Dental Length On Tooth Block Inner Dissipater

Inner energy dissipaters of tooth block is the proposed form of energydissipation, compared with the traditional form of energy dissipation, which is tosolve the shortage problem of the poor flow ability, and ensure the energydissipation,it is a kind of very potential energy dissipation, the researchsignificance is very significant. In the early，there have been in the form ofinternal energy dissipation work physical model test research was conducted onthe hydraulic characteristics, analysed the teeth number of the pier and areacontraction ratio on the properties and the effect of energy dissipation andpressure in this paper, based on this, using the current widely used turbulentnumerical simulation software package, Fluent software to carry on thenumerical simulation research, study the different dental length on dental shapehead loss coefficient of the kinetic energy dissipation, energy dissipation, alongthe wall when the pressure coefficient distribution, the section stress distributionand the distribution of the velocity vector of the clouds, through the analysis ofthe main conclusions are as follows:1. Under different flow rate, the shape of tooth pier shape head losscoefficient of the kinetic energy dissipation were similar, variation law isroughly same, visible flow has a little effect on the head loss coefficient.2. Under the same flow, head loss coefficient is relative to the eta range isnot big, about change between1.37~1.63, shows that dental period of relativelength η（η is the ratio of dental length L and pipe diameter D）has a little effect on the head loss coefficient, but in contrast, when the η=0.5, the smallesthead loss coefficient, the lowest energy dissipation; When η=0.1, head losscoefficient is the largest, the highest energy dissipation.3. When the η must be tooth pier shape within the dissipation of water flowwith the pipe increases.4. Under the same flow rate, along with the increase of η, first thedissipation is reduced, the flow rate, the greater the reduction of energydissipation, the greater the when η increases to0.5, the dissipation reaches theminimum value, with η continues to increase, the energy dissipation and rise,gradually stabilized.5. Different pier length of tooth pier shape within the wall when the flow ofthe pressure coefficient is broadly in line with a change rule along the path, andare relatively stable before dental segment, plummeted in dental import place, atthe pier segment tooth remain slow decline, the minimum value in the export ofdental location, and then gradually increase after dental segment, until the returnto a stable state.6. The shape of tooth profile of pressure on the pier shape clouddistribution broadly, the water pressure in the water when entering a dentalsegment disorder, right in front of dental rectangular area near the side wall ishigh, and in the dental inlet flow pressure sharply decreases, and the pressureminimum points from dental segment now import0.1D, uniform pressuredistribution in the dental interval, at the edge of the tooth behind the pier is nearthe wall rectangular area exists low pressure area, the whole calculation domaindoes not appear negative pressure, the pressure characteristics, good followdental tube length after continue to increase, pressure and gradually recoveredhis uniform.7. Velocity distribution appeared in front of the dental water shrinkage area,streamline appearance strong bending deformation, velocity were quickly,significantly reduced pressure, flow rate increases significantly, lead to the energy consumption. After entering dental segment, streamline become dense,numerical increase, then enter the sudden enlargement section, the velocity atthe edge of the tooth behind the pier is near the wall of the rectangular area andthe central part of the pipeline of the separation zone and backflow zone formedbetween mainstream beam, Z continues to increase, as along the pipe crosssection flow velocity and gradually recovered his uniform.8.Dental length changes on low pressure backflow zone, with the increaseof η, low pressure backflow zone length slightly shorter.