Simulación numérica experimental de un canal con un nuevo modelo de rugosidad artificial

Abstract

For channels housed in earth, covered in stone or concrete, the maximum speeds at which a fluid can circulate must be considered, because very high velocities of the water can cause erosion in the channel, dragging of material from the bed, washing of fine in this way, the channel loses its useful life very quickly and maintenance must be carried out very often, which makes the work more expensive. The use of artificial roughness in high slope channels has now been proposed for speed control, and in this way protect the channels from events that may deteriorate them. For the analysis of these elements Computational Fluid Dynamics (CFD) programs are used, which solve the Navier - Stokes flow governance equations iteratively, in this way, making it easier to analyze what can happen in the waterworks before its construction. Due to the increase in computational capacity, using this methodology has become simple for many case studies. In the present thesis work, the channel located in the Hydraulic and Fluid Mechanics Laboratory of the University of Cuenca is used as a base, to perform a numerical simulation by locating an artificial roughness model within the channel using the OpenFoam computational analysis tool and the post-processing tool Paraview. An initial calibration simulation is performed to replicate in the computational model all the variables that are measured in the laboratory, the absolute roughness coefficient for the channel is determined. Finally, three simulations are carried out, each with a different artificial roughness model, and then the effectiveness of each one is compared with the theoretical model. The artificial roughness model that best dissipates the energy or that further reduces the water velocity, using velocity and flow rate measurements, is determined