Modelado De La Velocidad De Corrosión Atmosférica De Acero De Baja Aleación en Costa Rica

Abstract

ResumenA partir de datos de velocidad de corrosión atmosférica y variables ambientales en diferentes sitios de Costa Rica, se realizan evaluaciones matemáticas de los modelos usuales utilizados para la estimación de la velocidad de corrosión (Vcorr). Estos datos de contaminantes y parámetros atmosféricos en conjunto con la velocidad de corrosión obtenida gravimétricamente, son modelados por medio de la aplicación "optimtool" de Matlab , obteniendo resultados mixtos entre los modelos utilizados. Como principal conclusión se tiene el desarrollo de la Ecuación 3, la cual presenta un modelo de mejor ajuste para cada uno de los sitios, obteniéndo valores adecuados de los parámetros de control (RSS, F y R 2 ), pero no así de la aplicación de las mismas en otros sitios. Palabras clave: Corrosión atmosférica, modelado, velocidad de corrosión, acero de baja aleación AbstractFrom corrosion atmospheric rate data and its relationship with environmental variables of different Costa Rica locations, mathematical evaluations of typical models for corrosion rate estimation, were performed. Contamination data and atmospheric parameters along with gravimetric corrosion rate are modeled through Matlab's application "optimtool", yielding mixed results for the models. As main result, the development of equation 3, delivers a model of best adjustment for each site, which generates aceptable values for control parameters (RSS, F y R 2 ), but not for the application of same model for other sites.

Prediction of atmospheric corrosion from meteorological parameters: Case of the atmospheric basin of the Costa Rican Western Central Valley

“…The Vcorr values from the simple linear models based on RH and TOW (equations 7 and 8, respectively), increased rapidly with altitude and correspond to C2 and C3 corrosivity categories, according to the ISO 9223:2012 standard (Table II) The model based of ISO 9223:2012 (equations 3 and 9) presented higher values with respect to observations. This problem was already pointed out in some studies carried out in the tropical atmosphere (Restrepo, et al, 2007;Corvo et al, 2008, Morcillo et al, 2012Morcillo et al, 2013, Garita, et al, 2014Rios et al, 2017;Vera et al, 2017).…”

“…Temperature and relative humidity variables are obtained from meteorological data, and the deposition of both chlorides and sulphur oxides is measured or estimated by air pollution evaluation methods. These parameters permit the characterization of the effects of pollution variation on the corrosion rate in the WCV (Morcillo et al, 1998;Roberge et al, 2002;Morcillo et al, 2012;Robles, 2013;Garita et al, 2014;Rodríguez-Yáñez et al, 2015;Alcántara et al, 2015;Morcillo, 2017). Garita et al (2014) proposed a series of models for obtaining corrosion rates depending on the available information.…”

Análisis de mixturas gaussianas de parámetros meteorológicos básicos: Temperatura y humedad relativa

“…In this first stage, the main objective is to model the distribution of temperature and relative humidity with Gaussian mixtures. Visualizing these distributions will allow to improve the models for weather forecast, and even more importantly, pollutant transport and particle deposition [1], [2].…”

“…Additionally, they have a direct relationship with the subject of corrosion [3], [4]. It is generally considered that relative humidity and temperature affect corrosion when having values above 80 % and 0 °C [1], [2], [3]. By isolating these conditions per area, it could be determined which regions could have higher corrosion levels in order to take it into account for the construction of metallic structures.…”