基于Tsallis熵的两点法确定明渠断面流速分布及数值模拟验证

Cross-section Velocity Distribution Determination by Two-point Method Based on Tsallis Entropy and Numerical Simulation Verification

在现代农业灌溉中,为了得到明渠断面的流量,首先需要确定明渠断面的流速分布,然而以往的流速分布公式大都不够准确,无法满足精准灌溉的需求,针对这一难题,在基于Tsallis熵推导流速分布的基础上,对熵参数重新推导,提出新的熵参数,进一步简化了流速分布公式,提出两点法确定断面流速分布的研究方法,并结合实测资料和数值模拟软件进行验证。结果表明:通过测量水面下断面中心线上一点流速值u_(c)与相同水深下另一点的流速值u_(z),可计算出流速分布公式中两个未知参数G_(p)、m_(p),确定该水深位置横向流速分布公式,再通过已知参数计算出断面最大流速u_(max),并确定断面中心线流速分布公式。与以往的流速分布公式相比,两点法更加简便,能够较好的应用在工程实际中,具有较高的理论意义和实用价值。

In modern agricultural irrigation,in order to obtain the flow rate of the open channel section,it is necessary to determine the velocity distribution of the open channel section first.However,most of the previous velocity distribution formulas are not accurate enough to meet the needs of precision irrigation.In this study,to solve this problem,on the basis of deducing the velocity distribution based on Tsallis entropy,the entropy parameters were rededuced,a new entropy parameter was proposed,the velocity distribution formula was further,and a two-point method was proposed to determine the velocity distribution of the section.The research method was verified by the measured data and numerical simulation software.The results show that:by measuring the velocity value u_(c) at one point on the center line of the section under the water surface and the velocity value u_(z) at another point under the same water depth,the two unknown parameters G_(p) and m_(p) in the velocity distribution formula can be calculated,and the transverse velocity distribution formula at the water depth position can be determined.Then the maximum velocity u_(max) of the section is calculated by the known parameters,and the velocity distribution formula of the center line of the section is determined.Compared with the previous velocity distribution formula,the two-point method is simpler.This formula can be better applied in engineering practice,and has high theoretical significance and practical value.