| In this study,the theory of dissipation pool optimization is summarized and related to domestic and foreign studies,and the relevant numerical simulation theory is briefly introduced.Taking the actual engineering as the research object,three factors affecting the numerical simulation results are selected for analysis,including the calculation range,the meshing form,and the turbulence model;after screening out the appropriate numerical simulation parameters,the most unfavorable working conditions and the most energydissipating and anti-impact design conditions are selected for the four operating conditions,and the numerical simulation is carried out on the selected working conditions,and the influence of the upstream and downstream water level difference and the single width flow rate of the gate on the single width energy of the gate is analyzed respectively.Finally,under the most unfavorable working conditions,the orthogonal test method is used to optimize the body type of the dissipation pool by the energy dissipation rate and the relative bottoming flow rate,and the optimal solution is obtained.After establishing three evaluation indicators of the body size,energy dissipation rate and relative bottom flow rate of the dissipative pool based on the response surface method,the optimized size combination scheme is smaller than the optimized body type combination scheme of the orthogonal test,and the body size of the dissipative pool is smaller,which puts forward a practical and feasible research method for the project.The main research contents are as follows:（1）First,three factors affecting the numerical simulation results were selected for analysis,including the calculation range,meshing form,and turbulence model,and the analysis results showed that the three factors had different degrees of influence on the calculation results.The specific analysis is as follows:1)The calculated length of the upstream section before the gate is similar to the length of the total width of the gate chamber,if the calculated length value exceeds the total width of the gate chamber,the impact on the calculation result is not obvious,so the calculated length of the upstream section before the gate is selected 90m.The calculated length downstream of the anti-flush tank has little impact on the hydraulic characteristics inside the anti-flush tank,and the calculated length of the downstream section of the anti-flush tank is 40m considered.2)The mesh division adopts four forms of division:non-uniform coarse mesh,non-uniform fine mesh,local encryption mesh based on coarse mesh and local encrypted mesh based on fine mesh,and the calculation results show that the grid size should be moderate,the smaller the mesh size,the higher the calculation accuracy,but the denser the calculation grid,the longer the calculation time,the increase in computational cost,so the local encryption mesh based on the coarse mesh can obtain the same or even more accurate results.3)In the selection of turbulence models,the calculation results of the four turbulence models of Standard k-ε.Realizable k-ε,RNG k-ε and LES are small compared with the data in the references,indicating that they are all suitable for turbulence numerical calculation.Considered comprehensively,the turbulence model using RNG k-ε is more suitable for water jump calculation.（2）After the numerical model parameters are determined,the maximum single width energy is obtained by the design condition of the sluice energy dissipation.First,the different gate degrees of the four energy dissipation and anti-impact conditions are calculated according to the design specifications of the sluice gate,and the single wide flow rate of the gate under each opening degree is calculated,and finally the energy consumption design conditions with the largest flow of the gate and the energy consumption verification 3 conditions with the largest water level difference between the upstream and downstream water levels are selected for numerical simulation,and the results of the numerical simulation are analyzed.It can be seen from the comparison between the calculated value of the single width flow and energy of the gate and the numerical simulation value that the opening degree of the energy dissipation design condition of 4.0m is the most unfavorable working condition of the sluice energy consumption design.（3）Under the most unfavorable working conditions of energy dissipation and antiimpact,the quadrature test of 25 kinds of absorption scale size combination schemes was carried out by using an orthogonal table of four factors and five levels.The results of orthogonal experiments show that the depth,length,diffusion angle and tail slope of the friction pool are analyzed numerically under the condition of considering the energy dissipation rate and the relative bottom flow rate.Without considering the body size of the sink,the optimal combination of size optimization of the orthogonal test of the cell size is the depth of the sink pool of 3.0 m,the length of 34 m,the diffusion angle of 14° and the slope of the tail ridge of 90°.（4）On the basis of the orthogonal experimental results,the multivariate regression fitting of the dissipation rate,the relative bottom flow rate and the comprehensive objective function are carried out by the response surface method,and the polynomial response surface regression equation between the objective function and the sinking pool depth,the length of the dissipative pool,the diffusion angle,and the slope of the tail cane are established under the condition of considering the body shape of the dissipation pool.Taking the depth of the dissipative pool,the length of the dissipative pool,the diffusion angle,and the slope of the tail ridge as the optimization design variables,the dissipation rate,the relative bottom flow rate and the comprehensive objective function as the target functions,the four-factor optimization design based on the response surface model is optimized,and the functional relation based on the quadratic polynomial response model is established.It is found that the interaction between the depth of the dissipative pool,the length of the dissipative pool and the slope of the tail ridge is significant,and the interaction between the depth of the dissipative pool and the slope of the tail ridge is greater than the interaction between the depth of the sinking pool and the length of the dissipation pool.For the sluice drainage pool in this paper,the optimal parameter combination is 2.88m deep,31.5m long,13.6°diffusion angle,and 87.4°tail slope.Under this combination of parameters,the dissipation rate is 61.9%,the relative bottoming flow rate is 1.384,which is 12.6%higher than the initial solution,and the relative bottoming flow rate is reduced by 7.11%.The research methods and results of this paper can provide improvement measures and suggestions for the study on the optimal design of the body type of the sluice sluice suction pool,which is of great significance to the optimization design of the sluice sluice pot body type.At the same time,it can also provide a certain reference for the optimization design and research of similar consumption pool body type. |
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