Simplified Mathematical Model for Computing Draining Operations in Pipelines of Undulating Profiles with Vacuum Air Valves

[EN] The draining operation involves the presence of entrapped air pockets, which are expanded during the phenomenon occurrence generating drops of sub-atmospheric pressure pulses. Vacuum air valves should inject enough air to prevent sub-atmospheric pressure conditions. Recently, this phenomenon has been studied by the authors with an inertial model, obtaining a complex formulation based on a system composed by algebraic-di erential equations. This research simplifies this complex formulation by neglecting the inertial term, thus the Bernoulli¿s equation can be used. Results show how the inertial model and the simplified mathematical model provide similar results of the evolution of main hydraulic and thermodynamic variables. The simplified mathematical model is also verified using experimental tests of air pocket pressure, water velocity, and position of the water column.Coronado-Hernández, ÓE.; Fuertes-Miquel, VS.; Quiñones-Bolaños, EE.; Gatica, G.; Coronado-Hernández, JR. (2020). Simplified Mathematical Model for Computing Draining Operations in Pipelines of Undulating Profiles with Vacuum Air Valves. Water. 12(9):1-12. https://doi.org/10.3390/w12092544S112129Fuertes-Miquel, V. S., Coronado-Hernández, O. E., Mora-Meliá, D., & Iglesias-Rey, P. L. (2019). Hydraulic modeling during filling and emptying processes in pressurized pipelines: a literature review. Urban Water Journal, 16(4), 299-311. doi:10.1080/1573062x.2019.1669188Fuertes-Miquel, V. S., Coronado-Hernández, O. E., Iglesias-Rey, P. L., & Mora-Meliá, D. (2018). Transient phenomena during the emptying process of a single pipe with water–air interaction. Journal of Hydraulic Research, 57(3), 318-326. doi:10.1080/00221686.2018.1492465Tijsseling, A. S., Hou, Q., Bozkuş, Z., & Laanearu, J. (2015). Improved One-Dimensional Models for Rapid Emptying and Filling of Pipelines. Journal of Pressure Vessel Technology, 138(3). doi:10.1115/1.4031508Coronado-Hernández, O. E., Fuertes-Miquel, V. S., Besharat, M., & Ramos, H. M. (2018). Subatmospheric pressure in a water draining pipeline with an air pocket. Urban Water Journal, 15(4), 346-352. doi:10.1080/1573062x.2018.1475578Ramezani, L., Karney, B., & Malekpour, A. (2016). Encouraging Effective Air Management in Water Pipelines: A Critical Review. Journal of Water Resources Planning and Management, 142(12), 04016055. doi:10.1061/(asce)wr.1943-5452.0000695Zhou, L., & Liu, D. (2013). Experimental investigation of entrapped air pocket in a partially full water pipe. Journal of Hydraulic Research, 51(4), 469-474. doi:10.1080/00221686.2013.785985Carlos, M., Arregui, F. J., Cabrera, E., & Palau, C. V. (2011). Understanding Air Release through Air Valves. Journal of Hydraulic Engineering, 137(4), 461-469. doi:10.1061/(asce)hy.1943-7900.0000324Bianchi, A., Mambretti, S., & Pianta, P. (2007). Practical Formulas for the Dimensioning of Air Valves. Journal of Hydraulic Engineering, 133(10), 1177-1180. doi:10.1061/(asce)0733-9429(2007)133:10(1177)Ramezani, L., Karney, B., & Malekpour, A. (2015). The Challenge of Air Valves: A Selective Critical Literature Review. Journal of Water Resources Planning and Management, 141(10), 04015017. doi:10.1061/(asce)wr.1943-5452.0000530Coronado-Hernández, O., Fuertes-Miquel, V., Besharat, M., & Ramos, H. (2017). Experimental and Numerical Analysis of a Water Emptying Pipeline Using Different Air Valves. Water, 9(2), 98. doi:10.3390/w9020098Laanearu, J., Annus, I., Koppel, T., Bergant, A., Vučković, S., Hou, Q., … van’t Westende, J. M. C. (2012). Emptying of Large-Scale Pipeline by Pressurized Air. Journal of Hydraulic Engineering, 138(12), 1090-1100. doi:10.1061/(asce)hy.1943-7900.0000631Coronado-Hernández, O. E., Fuertes-Miquel, V. S., Iglesias-Rey, P. L., & Martínez-Solano, F. J. (2018). Rigid Water Column Model for Simulating the Emptying Process in a Pipeline Using Pressurized Air. Journal of Hydraulic Engineering, 144(4), 06018004. doi:10.1061/(asce)hy.1943-7900.0001446Coronado-Hernández, O. E., Fuertes-Miquel, V. S., Iglesias-Rey, P. L., & Martínez-Solano, F. J. (2020). Closure to «Rigid Water Column Model for Simulating the Emptying Process in a Pipeline Using Pressurized Air» by Oscar E. Coronado-Hernández, Vicente S. Fuertes-Miquel, Pedro L. Iglesias-Rey, and Francisco J. Martínez-Solano. Journal of Hydraulic Engineering, 146(3), 07020002. doi:10.1061/(asce)hy.1943-7900.0001681Vasconcelos, J. G., & Wright, S. J. (2008). Rapid Flow Startup in Filled Horizontal Pipelines. Journal of Hydraulic Engineering, 134(7), 984-992. doi:10.1061/(asce)0733-9429(2008)134:7(984)Vasconcelos, J. G., Klaver, P. R., & Lautenbach, D. J. (2014). Flow regime transition simulation incorporating entrapped air pocket effects. Urban Water Journal, 12(6), 488-501. doi:10.1080/1573062x.2014.881892Wang, L., Wang, F., & Lei, X. (2018). Investigation on friction models for simulation of pipeline filling transients. Journal of Hydraulic Research, 56(6), 888-895. doi:10.1080/00221686.2018.1434693Malekpour, A., Karney, B. W., & Nault, J. (2016). Physical Understanding of Sudden Pressurization of Pipe Systems with Entrapped Air: Energy Auditing Approach. Journal of Hydraulic Engineering, 142(2), 04015044. doi:10.1061/(asce)hy.1943-7900.0001067Coronado-Hernández, Ó. E., Fuertes-Miquel, V. S., Mora-Meliá, D., & Salgueiro, Y. (2020). Quasi-static Flow Model for Predicting the Extreme Values of Air Pocket Pressure in Draining and Filling Operations in Single Water Installations. Water, 12(3), 664. doi:10.3390/w12030664Leon, A. S., Ghidaoui, M. S., Schmidt, A. R., & Garcia, M. H. (2010). A robust two-equation model for transient-mixed flows. Journal of Hydraulic Research, 48(1), 44-56. doi:10.1080/0022168090356591

Methodology for selecting atmospheric monitoring sitesin urban areas affected by emissions from mobile sources

El monitoreo atmosférico es una de las etapas fundamentales en la identificación de estrategias para minimizar, prevenir y controlar los impactos de la dispersión de contaminantes en el aire, sobre la salud pública y el ambiente. Por tanto, el objetivo principal de este articulo consiste en proponer una metodología para la selección de  sitios de monitoreo atmosférico en zonas urbanas afectadas por las emisiones de fuentes móviles. Primeramente se identificaron los sitios que presentaban mayor flujo vehicular y se priorizaron teniendo presente  los siguientes  criterios  de selección: seguridad, influencia de otras fuentes, facilidad del montaje de los equipos,  accesibilidad al sitio, identificación de barreras y obstáculos,  registro histórico de datos  y grado de concentración  usando el software CALINE 3.La modelación agrupo datos característicos de las vías, meteorológicos y de flujo vehicular de un año típico de la zona en estudio.   A cada uno de estos parámetros le es asignada una valoración cuantitativa, la cual define los sitios donde se realizará el monitoreo. Como resultados se desarrolló una guía para seleccionar los lugares en donde se puedan desarrollar campañas de monitoreo atmosférico asociadas a fuentes móviles. La metodología fue aplicada en la ciudad de Cartagena de Indias haciendo uso del modelo de calidad del aire CALINE3.Atmospheric monitoring is one of the fundamental steps in identifying strategies to minimize, prevent and control the impact of the dispersion of pollutants in the air, on public health and the environment. Therefore, the main objective of this article is to propose a methodology for selecting air monitoring sites in urban areas affected by emissions from mobile sources. First, the places with the highest vehicular flow were identified and prioritized according to the following selection criteria: safety, influence of other sources, ease of assembly of equipment, accessibility to the site, identification of barriers and obstacles, historical record of data and degree concentration of the pollutant: in this case carbon monoxide, using CALINE 3 software. The modeling grouped characteristic data related with roads, meteorology and vehicular flow of a typical year of the zone under study. A quantitative assessment is assigned to each of these parameters, which defines the sites where the monitoring will be performed. As a result, it was developed a guide to select those places where atmospheric monitoring campaigns related with mobile sources can be held. This methodology was applied in the city of Cartagena de Indias by using air quality model for assessment, CALINE

Methodology for selecting atmospheric monitoring sitesin urban areas affected by emissions from mobile sources

El monitoreo atmosférico es una de las etapas fundamentales en la identificación de estrategias para minimizar, prevenir y controlar los impactos de la dispersión de contaminantes en el aire, sobre la salud pública y el ambiente. Por tanto, el objetivo principal de este articulo consiste en proponer una metodología para la selección de  sitios de monitoreo atmosférico en zonas urbanas afectadas por las emisiones de fuentes móviles. Primeramente se identificaron los sitios que presentaban mayor flujo vehicular y se priorizaron teniendo presente  los siguientes  criterios  de selección: seguridad, influencia de otras fuentes, facilidad del montaje de los equipos,  accesibilidad al sitio, identificación de barreras y obstáculos,  registro histórico de datos  y grado de concentración  usando el software CALINE 3.La modelación agrupo datos característicos de las vías, meteorológicos y de flujo vehicular de un año típico de la zona en estudio.   A cada uno de estos parámetros le es asignada una valoración cuantitativa, la cual define los sitios donde se realizará el monitoreo. Como resultados se desarrolló una guía para seleccionar los lugares en donde se puedan desarrollar campañas de monitoreo atmosférico asociadas a fuentes móviles. La metodología fue aplicada en la ciudad de Cartagena de Indias haciendo uso del modelo de calidad del aire CALINE3.Atmospheric monitoring is one of the fundamental steps in identifying strategies to minimize, prevent and control the impact of the dispersion of pollutants in the air, on public health and the environment. Therefore, the main objective of this article is to propose a methodology for selecting air monitoring sites in urban areas affected by emissions from mobile sources. First, the places with the highest vehicular flow were identified and prioritized according to the following selection criteria: safety, influence of other sources, ease of assembly of equipment, accessibility to the site, identification of barriers and obstacles, historical record of data and degree concentration of the pollutant: in this case carbon monoxide, using CALINE 3 software. The modeling grouped characteristic data related with roads, meteorology and vehicular flow of a typical year of the zone under study. A quantitative assessment is assigned to each of these parameters, which defines the sites where the monitoring will be performed. As a result, it was developed a guide to select those places where atmospheric monitoring campaigns related with mobile sources can be held. This methodology was applied in the city of Cartagena de Indias by using air quality model for assessment, CALINE

Metodología para la selección de sitios de monitoreo atmosférico en zonas urbanas afectada por las emisiones de fuentes móviles

El monitoreo atmosférico es una de las etapas fundamentales en la identificación de estrategias para minimizar, prevenir y controlar los impactos de la dispersión de contaminantes en el aire, sobre la salud pública y el ambiente. Por tanto, el objetivo principal de este articulo consiste en proponer una metodología para la selección de  sitios de monitoreo atmosférico en zonas urbanas afectadas por las emisiones de fuentes móviles. Primeramente se identificaron los sitios que presentaban mayor flujo vehicular y se priorizaron teniendo presente  los siguientes  criterios  de selección: seguridad, influencia de otras fuentes, facilidad del montaje de los equipos,  accesibilidad al sitio, identificación de barreras y obstáculos,  registro histórico de datos  y grado de concentración  usando el software CALINE 3.La modelación agrupo datos característicos de las vías, meteorológicos y de flujo vehicular de un año típico de la zona en estudio.   A cada uno de estos parámetros le es asignada una valoración cuantitativa, la cual define los sitios donde se realizará el monitoreo. Como resultados se desarrolló una guía para seleccionar los lugares en donde se puedan desarrollar campañas de monitoreo atmosférico asociadas a fuentes móviles. La metodología fue aplicada en la ciudad de Cartagena de Indias haciendo uso del modelo de calidad del aire CALINE3.Atmospheric monitoring is one of the fundamental steps in identifying strategies to minimize, prevent and control the impact of the dispersion of pollutants in the air, on public health and the environment. Therefore, the main objective of this article is to propose a methodology for selecting air monitoring sites in urban areas affected by emissions from mobile sources. First, the places with the highest vehicular flow were identified and prioritized according to the following selection criteria: safety, influence of other sources, ease of assembly of equipment, accessibility to the site, identification of barriers and obstacles, historical record of data and degree concentration of the pollutant: in this case carbon monoxide, using CALINE 3 software. The modeling grouped characteristic data related with roads, meteorology and vehicular flow of a typical year of the zone under study. A quantitative assessment is assigned to each of these parameters, which defines the sites where the monitoring will be performed. As a result, it was developed a guide to select those places where atmospheric monitoring campaigns related with mobile sources can be held. This methodology was applied in the city of Cartagena de Indias by using air quality model for assessment, CALINE

Spatial variability study of rainfall in Cartagena de Indias, Colombia

Precipitation is a component of the hydrological cycle, knowing its spatial distribution is vital for the management of hydrographic basins, the territory and the development of fundamental activities for society. That is why the present study shows the spatial variability of rainfall in Cartagena de Indias city with a network of rain gauges, made up of nine pieces of equipment, separated from each other by 0.9-27 km. After a year of recording (2019), using historical series of data, it was found that the maximum rainfall occurs in the trimester between September and November, with interpolated maps made by the Ordinary Kriging (OK) method it was found that the maximum rainfall is focused on the north, centre and west of the territory, instead, the maximum intensities are presented in the centre and west, the minimums for both variables are presented to the east and south. The 70 and 90% of the rain events have a duration of less than 30 min and 1 h, respectively. Three-parameter exponential function was fitted to the paired correlation distances, and presented correlations lower than 0.8, 0.5 and 0.2 from distances of 1, 3 and 7 km, respectively, in 30 min rain integration. It was also found that with a pluviometric network conformed by at least six pieces of equipment and separated by a 5 km distance from each other in the urban area, a correlation of 0.5 and compliance with the WMO recommendations would be obtained

Dynamic effects of a regulating valve in the assessment of water leakages in single pipelines

Water losses in water distribution systems are typically analysed using extended period simulations, where its numerical resolution is commonly achieved using the gradient method. These models assume that adjustments to regulating valves occur, either manually or automatically, over an extended period of time, then the system inertia can be neglected. This research introduces the development of a rigid water column model for analysing water leakages in single pipelines, which can be employed to account for regulation valve adjustments in shorter time periods, thereby providing greater accuracy when assessing water losses. The application to a case study is presented to analyse pressure variations and leakage flow patterns over 30, 60, and 180 s. A comparison between the extended period simulation and rigid water column model is presented in order to note the order of magnitude on leakages when the system inertia is not considered. The results confirm that is crucial for water utilities the consideration of inertial system to simulate adequately opening and closure manoeuvres in water distribution systems, since according to the case study the extended period simulation can overestimated or underestimated the total leakage volume in percentages of 37.1 and 55.2 %, respectively