Determination of the most efficient type of landfill according to the precision of its theoretical and regression equation regarding the experimental data.

Abstract

Introduction: Weirs are considered as hydraulic structures on which a liquid is discharged. These structures are employed to regulate or measure flow rates, with the use of theoretical or regression models, when it is not possible to perform a volumetric gauging –hence the importance of their accuracy–. In this study, the error of the equations with respect to the data obtained in the laboratory is determined by volumetric gauging in each type of weir: rectangular, trapezoidal, triangular, circular and sutro weir. Objective: to determine the most accurate type of weir, comparing the results of each equation with those obtained in the laboratory. Methodology: first, it was verified that the weirs fulfilled the necessary conditions, and the corresponding measurements were taken at the time of the installation (B, b, θ, D, e, w). Then, each weir was installed in the proper way: covering possible leaks, regulating the flow of the tank that supplied the weir, and measuring w and Ht, all this to perform the volumetric gauging with different hydraulic loads. Finally, the calculations were done, comparing results, and finding the most accurate equation. Results: regarding the theoretical equation, the triangular weir had an average error of 8.6%, a standard deviation of 7.08, a coefficient of variation of 81.8%, a minimum of 1.8 and a maximum of 29 4. In relation to the regression equation, the circular weir had an average error of 2.2%, a standard deviation of 2.14, a coefficient of variation of 55.4%, a minimum of 1.34 and a maximum of 4, 22). Conclusion: regarding the theoretical equation, the most effective and efficient weirs were the triangular one (8.6% error) followed by the sutro one (9.2% error), while, the least effective and efficient weir was the trapezoidal (53.0% error). On the other hand, according to the regression equation, the best weir was the circular one (97.8% precision), followed by the sutro one (97.7% precision); and the least effective weirs, were the rectangular one (96.8% precision), and the trapezoidal (93.8% precision). Because of that, the recommended weir is the circular one. In addition, all the analyzes presented in the  graphs determined a directly proportional relationship between the hydraulic charge and the flow, while the discharge coefficient tended to remain constant between a range of specific values for each weir without presenting a considerable variation with respect to the hydraulic charge.