抛物线形断面最优水力参数及方程指数计算方法

Calculation of open channel section optimum hydraulic parameters and parabolic index parabola

针对目前抛物线形断面最优水力参数及抛物线方程指数计算尚没有比较系统研究成果的问题,通过对该种断面均匀流方程的变形整理及近似积分计算,得到了抛物线方程指数一定情况下明渠过水断面最优水力参数的简化计算公式,并通过对简化公式的进一步分析整理,给出了当渠道其他参数(流量、比降及糙率)一定情况下抛物线形断面的最优方程指数为3.35。精度分析及算例计算结果表明:最优水力参数的提出将为该类断面的进一步优化设计提供可靠依据;最优抛物线形断面比其他水力最优断面经济指标更好。

A relatively systematic study on the optimum hydraulic parameter of parabolic transaction and the calculation of parabolic optimum index have been studied in this paper. Through sorting out the variants and calculating the approximate integration of the equation of unifiorm flow for such transaction, this essay presents the simplified formula for the optimum hydraulic parameter of the open-channel water-flowing transaction in case of a given parabolic equation index. By analyzing the simplified equation, we found a new optimum equation index of parabolic transaction to be 3.35 on the condition that other parameters of the open-channel such as water flow, gradient and roughness stay unchanged. Our finds also show that the presentation of the optimum hydraulic parameter serves as the basis for the turther optimization design of parabolic transaction. Additionally, through the comparison of the optimum index of parabolic transaction and other hydraulic optimum transactions, the optimum index of parabolic transaction shows a higher economic indicator and therefore, it is worth extending the application.