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Hydrology Days

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https://hdl.handle.net/10217/199983
Each year the American Geophysical Union "Hydrology Days" meeting brings together water scientists, researchers, and students to discuss the current state of the science and latest water-related research findings. Digital copies of the meetings from 2000-2018 may be found here. Digital copies of the meetings from 2019- are published in issues of the Colorado Water Center newsletter.

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Browsing Hydrology Days by Author "Andrade, Carla Freitas, author"

Now showing 1 - 4 of 4
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    Application of fuzzy set theory on the Saint Venant equations to study flood wave propagation in natural rivers
    (Colorado State University. Libraries, 2010) Ueta, Vanessa, author; Chagas, Patrícia Freire, author; Santos, Silvia Helena, author; Andrade, Carla Freitas, author; Souza, Raimundo, author; Colorado State University, publisher
    The knowledge of the propagation of flood waves, in natural channels, through Saint Venant's equations, has been object of studies on the part of engineers and scientists, along years. With the progress of the digital computers, the mathematical models become a great option, in the analysis of this class problem. In this context, the uses of numerical models, in the treatment of the hydrodynamic models, has allowed more select studies of the behavior of the flood routing to be accomplished. This work treats of the study of a flood wave, through a simplified methodology, for solution of the equations of the hydrodynamic that allows the use of a numerical model with explicit solution. The influence of hydraulic parameters, inherent to the natural river, it is considered. The results show that this methodology had a great acting and it constitutes in a good way for the study of this class of problem.
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    Application of fuzzy set theory to flood risk analysis in natural rivers as a function of hydraulic parameters
    (Colorado State University. Libraries, 2010) Santos, Silvia Helena, author; Chagas, Patrícia Freire, author; Andrade, Carla Freitas, author; Ueta, Vanessa, author; Souza, Raimundo, author; Colorado State University, publisher
    A mathematical model based on the Saint-Venant hydrodynamic equations, combined with fuzzy set theory, is developed in order to study the influence of hydraulic parameter of Natural River on the flood risk. To do so, the set of differential equations, in FUZZY formulation, is solved by numerical difference method, so that the membership functions of all control variables related with the flow could be calculated. With base in these membership functions the model is capable of evaluating the fuzzy risk for such area subjected to the flood process during intense rains. A computer program QUARIGUA (Risk Quantitative Analysis of Flooding in Urban Rivers) is used to perform the simulations. The computer program QUARIGUA is organized in a modular manner, with two main modules: the deterministic module, where the depth of the water in the river and the flow of the channel are calculated as discreet values; and the fuzzy module, based on the fuzzy set theory, where the depth of the water and the flow are calculated as membership functions. The simulations demonstrate the reliability, versatility and computational efficiency of the proposed model to evaluate fields of risk and reliability in hydrodynamics systems.
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    Application of mathematical modeling to study flood wave behavior in natural rivers as function of hydraulic and hydrological parameters of the basin
    (Colorado State University. Libraries, 2010) Chagas, Patrícia Freire, author; Santos, Silvia Helena, author; Andrade, Carla Freitas, author; Ueta, Vanessa, author; Souza, Raimundo, author; Colorado State University, publisher
    This research concerns about the development and application of a mathematical model, based on the Saint-Venant hydrodynamic equations, to study the behavior of the propagation of a flood wave in Natural River. The model is capable of evaluating the behavior of the control variables related to the flow in terms of the hydraulic and hydrological parameters of the basin. The governing partial differential equations are solved with the aid of finite differences, and for the solution of the system of nonlinear algebraic equations the iterative Newton-Raphson algorithm is employed. A computer program QUARIGUA (Risk Quantitative Analysis of Flooding in Urban Rivers) is used to perform the simulations. To evaluate the behavior of the control variables, several scenarios for the main channel as well as for the flood waves are considered and different simulations are performed. The simulations demonstrate that roughness coefficient and bed slope of the channel play a strong game on the behavior of the flood wave propagation.
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    Flood risk analysis of Cocó urban river in Fortaleza, Brazil
    (Colorado State University. Libraries, 2010) Andrade, Carla Freitas, author; Ueta, Vanessa, author; Chagas, Patrícia Freire, author; Santos, Silvia Helena, author; Souza, Raimundo, author; Colorado State University, publisher
    A mathematical model based on the Saint-Venant hydrodynamic equations combined with fuzzy set theory is formulated for the flood risk analysis of Cocó urban river in Fortaleza, Ceará, Brazil, which is subjected to the propagation of a flood wave. The model is capable of evaluating the behavior of the control variables related to the flow in terms of the hydraulic and hydrological parameters of the basin. The model is also capable of evaluating the fuzzy risk for such area subjected to the flood process during intense rains. The governing partial differential equations are solved with the aid of finite differences, and for the solution of the system of nonlinear algebraic equations the iterative Newton-Raphson algorithm is employed. A computer program QUARIGUA (Risk Quantitative Analysis of Flooding in Urban Rivers) is used to perform the simulations. The computer program QUARIGUA is organized in a modular manner, with two main modules: the deterministic module, where the depth of the water in the river and the flow of the channel are calculated as discreet values; and the fuzzy module, based on the fuzzy set theory, where the depth of the water and the flow are calculated as membership functions. To evaluate the behavior of the control variables, several scenarios for the main channel as well as for the flood waves are considered and different simulations are performed. The simulations demonstrate the reliability, versatility and computational efficiency of the proposed model.