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Diseño y alternativas en la instalación de inyectores Venturi en riego localizado1 Rev. Ciênc. Agron.
Manzano,Juan; Palau,Carmen Virginia; Azevedo,Benito Moreira de; Bomfim,Guilherme Vieira do; Vasconcelos,Denise Vieira.
En la UniversitatPolitécnica de València, Valencia, Espana (39°29' N; 0°23' W; 20 m), ha sido estudiado el funcionamiento de cuatro prototipos de inyector Venturi y tres formas de instalación distintas. El funcionamiento se ha analizado bajo diversos parâmetros, como pérdidas de carga, relación de caudales y rendimiento. Las formas de instalación analizadas han sido: sin inyección y con inyección y presiones negativas o positivas en la garganta. Las presiones se establecieron entre 10 y 40 m.c.a. A partir de los datos experimentales han sido procesados utilizando técnicas de regresión múltiple y análisis de la varianza. Con ellas, fue posible, a través de la integración de geometrías en función de los diâmetros, caudales y presiones, obtener expresiones...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Riego presurizado; Quimigación; Fertirigación.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902015000200287
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Characterization and selection method of Venturi injectors for pressurized irrigation Rev. Ciênc. Agron.
Manzano,Juan; Palau,Carmen Virginia; Azevedo,Benito Moreira de; Bomfim,Guilherme Vieira do; Vasconcelos,Denise Vieira.
ABSTRACT Venturi-type chemigation injectors are widely used due to their advantages: they do not require electric power and are cheap to operate. However, they also generate considerable energy losses which affect the pressure in the system. The correct characterization of these systems requires pressures to be correctly set at the inlet, injector and outlet points in relation to main and injected solution flows. These analytical relationships, as described in the International Organization for Standardization’s standard ISO 15873:2002, can be obtained theoretically, although it is recommended that the manufacturer should determine the real behavior of the injector by operational tests. These relationships should also be provided graphically in the form of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chemigation; Fertigation; Head losses; Nomography.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902018000200201
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Numerical study of upstream disturbances on the performance of electromagnetic and ultrasonic flowmeters Scientia Agricola
Palau,Carmen Virginia; Bomfim,Guilherme Vieira do; Azevedo,Benito Moreira de; Peralta,Iban Balbastre.
ABSTRACT Electromagnetic and ultrasonic flowmeters are high precision devices that can measure the water flow in pressurized irrigation networks. In these networks, the inadequate installation distance of flow control valves generates upstream disturbances which will increase measurement errors and reduce the accuracy of the equipment. Therefore, estimating these errors is important to establishing the correct installation distance of the hydraulic accessories and to ensuring the metrological reliability of the flowmeters. This work proposes a numerical study using Computational Fluid Dynamics to evaluate water flow behavior in pipes and estimate measurement errors caused by gate and butterfly valves in installation configurations found at pressurized...
Tipo: Info:eu-repo/semantics/other Palavras-chave: CFD; Pressurized irrigation; Water flowmeter; Water supply network.
Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162020000401602
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DIMSUB, a computer program for designing microirrigation subunits. Tool definition and case studies Scientia Agricola
Palau,Carmen Virginia; Arviza,Jaime; Balbastre,Iban; Manzano,Juan.
ABSTRACT: DIMSUB is a computer program to complement a decision support tool (DST) to effectively study different hydraulic design alternatives in microirrigation systems. We developed environments in Visual Basic for applications for Microsoft Excel® that allow specific step-by-step functions to be created for the design of irrigation subunits. Different alternatives can be considered, such as types of emitter, lateral and submain pipe sizes, different feeding points, irregular subunit shapes and topography slopes. Furthermore, specific uniformity criteria need to be considered to achieve efficient water applications and proper design systems. Lengths of run lateral and submain pipes, position of the hydrant connection, pressure head and head loss in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Irrigation; Emission uniformity; Dripper; Manifold.
Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162020000300100
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