A Lagrangian model for spray behaviour within vine canopies

Silva, Arthur da; Sinfort, Carole; Tinet, C.; Pierrat, Daniel; Huberson, S.

doi:10.1016/j.jaerosci.2005.05.016

Cited by 57 publications

(39 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Measurements relating to these three sets of posts were taken at 30 cm intervals, starting from a height of 30 cm above the ground and continuing to a height of 3.0 m and then at 50 cm intervals up to a maximum height of 4.5 m. Additional horizontal posts (labelled B), positioned at a height of 1.8 m, were used to take measurements at 20 cm intervals from the centre of the fan to the position corresponding to post A. Measurements were taken at a total of 201 different points (67 points per plane, in three planes). In similar studies, only one side of the sprayer was considered (Da Silva et al, 2006;Endalew et al, 2010aEndalew et al, ,b, 2011Endalew et al, , 2012Duga et al, 2013), although it is well known that air distribution of axial fans is asymmetric. This as- …”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Description of the airflow produced by an air-assisted sprayer during pesticide applications to citrus

Salcedo¹,

Garcerá²,

Granell³

et al. 2015

Span. j. agric. res.

View full text Add to dashboard Cite

Atmospheric drift of plant protection products is considered a major source of air pollution during pesticide applications. Citrus protection against pests and diseases usually requires application of these products using air-blast sprayers. Many authors have emphasized the influence of vegetation on the risk of spray drift. The aim of this work was to describe in detail how the airflow from an air-blast sprayer behaves when it reaches citrus trees and, in particular, the effect that the tree canopy has on this flow. Tests were conducted at a commercial citrus orchard with conventional machinery, placed parallel to a row of trees. Air velocity and direction was measured using a 3D ultrasonic anemometer in 225 points situated in three parallel planes perpendicular to the equipment. The stability of the airflow at each measuring point was studied and the mean velocities were graphically represented. Two vortexes, one behind the canopy, and another over the tree, have been deducted and never been reported before. Both may have an important influence on the trajectories of the sprayed droplets and, as a consequence, on the way in which plant protection products are diffused into the atmosphere. Observed turbulence intensities were higher than in similar experiments conducted in other tree crops, which may be attributable to the higher air volume generated by the machinery used for citrus protection and to the higher foliage density of citrus orchards.

show abstract

Section: Methodsmentioning

confidence: 99%

“…It is important to note that in tests performed in other crops such as vineyards (Da Silva et al, 2006) and pear orchards (Endalew et al, 2010a,b), it was observed that the airflow crossed the vegetation in the horizontal component. Therefore, U y was positive both when entering and leaving the vegetation.…”

Section: Velocities Analysis Of the Main Experimentsmentioning

confidence: 96%

Description of the airflow produced by an air-assisted sprayer during pesticide applications to citrus

Salcedo¹,

Garcerá²,

Granell³

et al. 2015

Span. j. agric. res.

View full text Add to dashboard Cite

show abstract

“…La salida de aire estaba alineada con el tronco delárbol (Figura 3). Este experimento está basado en un trabajo de campo realizado por Da Silva et al (2006) ventiladores axiales es asimétrica, los fabricantes reducen esta asimetría mediante la inclusión de deflectores de aire y mejoras en el diseño de sus ventiladores.…”

Section: Obtención De Los Datos Experimentalesunclassified

“…Cuando la corriente de aire atraviesa elárbol, se produce una caída de presión y una pérdida de energía. Por esa razón, varios autores han considerado la vegetación como un medio poroso a la hora de modelar con CFD los tratamientos fitosanitarios (Da Silva et al, 2006;Endalew et al, 2010). Estos modelos sirven para: 1) estudiar la deposición de los fitosanitarios sobre la vegetación, 2) estimar las posibles pérdidas que se puedan producir hacia la atmósfera y al suelo por deriva y 3) analizar el efecto de determinados parámetros (condiciones de la maquinaria, climatología o tipo de cultivo sobre la eficiencia de la aplicación).…”

Section: Introductionunclassified

Introduciendo la dinámica de fluidos computacional en el análisis de flujos en medio poroso

Salcedo

Bayón

Chueca

2017

Model. Sci. Educ. Learn.

View full text Add to dashboard Cite

Introduciendo la dinámica de fluidos computacional en el análisis de flujos en medio poroso Introducing computational fluid dynamics in the analysis of porous medium flows AbstractEste trabajo presenta una introducción a la modelización con Dinámica de Fluidos Computacional (CFD) de un fluido atravesando un medio poroso. Para ello, se propone un caso práctico mediante la simulación de un flujo de aire producido por el ventilador de un pulverizador hidráulico asistido por aire que atraviesa un medio poroso (la vegetación). El trabajo consiste en dotar de las herramientas necesarias para configurar un modelo CFD para, posteriormente, ajustar la resistencia de la porosidad al paso de la corriente usando datos experimentales. El ajuste contempla tres escenarios: uno, considerando sólo pérdi-das inerciales iguales entre los diferentes cuerpos porosos, dos, considerando dichas pérdidas inerciales más las pérdidas viscosas y, tres, considerando sólo pérdidas inerciales diferentes entre los diferentes cuerpos porosos. Finalmente, se comparan las velocidades obtenidas en cada simulación con datos reales, eligiéndose aquella configuración que arroja mayores ajustes. La metodología planteada pretende poner de manifiesto la importancia de usar con criterio los distintos parámetros propios de la configuración de modelos CFD. This paper presents an introduction about how to model a flow through a porous medium with Computational Fluid Dynamics (CFD). To this end, a case study is proposed by simulating an air current produced by the fan of an air assisted sprayer through a porous medium (vegetation). The work is aimed at adjusting the porosity resistance to the airflow using experimental data. The adjustment assesses three scenarios: one, considering only equal inertial losses between different porous bodies, two, considering both inertial losses and viscous losses and, three, considering only different inertial losses between different porous bodies. Finally, velocities obtained in each simulation are compared with experimental data. The proposed methodology highlights the importance of employing suitable parameters when configuring CFD models.

show abstract

“…Airassisted sprayers (e.g. the motorized knapsack mistblower) use air jets to carry pesticide droplets to the target position, to displace the air inside the crop canopy and to assist a uniform deposition of the pesticide droplets on the targeted surface (Sidahmed and Brown, 2001;Delele et al, 2005;DaSilva et al, 2006). In addition to the precision spray, offered by such equipments problems arising from the availability and transport of water can be alleviated by reducing dosage volumes during application.…”

Section: Introductionmentioning

confidence: 99%

Combined effect of applied equipment and formulation of pesticide on spray and dust drift in relation to harmful effects for some non-target organisms

Zaalok¹,

Abouelkassem²

2011

ABJNA

View full text Add to dashboard Cite

In Dakalt village, Kafrelshikh governorate, Egypt, field and laboratory studies were conducted in summer 2008 to investigate drift of Cyanophos applied on cotton field onto adjacent maize plants. Drift deposits of Cyanophos was determined as µg/kg maize leaves. The determinations were conducted on leaves of maize grown at various distances from the edge of the treated cotton fields (i.e. 5, 8, 14. up to 51 m). Distances traveled by drift in the 1st spray were farther than those of the 2nd spray. This result could be easily explained on the basis that wind speed was higher in 1st spray (wind speeds were 3.8 and 2.6 km/hr during time of application in the 1st and 2nd sprays, respectively). The farthest distance within maize field reached by drift was observed for the dust application followed by micron ULVA and mistblower spraying (the distances were 26, 35 and 44 m in the first spray when using the mistblower, micron ULVA and the mistblower as a duster, respectively). The corresponding values of drift deposits were 18.5, 13.6 and 28.4 µg/kg maize leaves, respectively. The potential drift emitted by micron ULVA compared with that of mistblower may be due to the smaller droplets of the former sprayer. Drift of Cyanophos released by each of the tested equipment caused 100% mortality of fish or honeybees placed at the distances 5 and 8 m from the edge of treated cotton field. For the dust application, 100% mortality was observed at longer distances (14 and 17 m). The study suggests that buffer zones (no spray zones) have to be established downwind of the treated field to avoid environmental contamination due to off-target deposition of pesticide drift. The model and specifications of these zones depend variably on quality of spray, release height, wind speed and other factors. Other measures of drift mitigation have to be considered.

show abstract

A Lagrangian model for spray behaviour within vine canopies

Cited by 57 publications

References 30 publications

Description of the airflow produced by an air-assisted sprayer during pesticide applications to citrus

Description of the airflow produced by an air-assisted sprayer during pesticide applications to citrus

Introduciendo la dinámica de fluidos computacional en el análisis de flujos en medio poroso

Combined effect of applied equipment and formulation of pesticide on spray and dust drift in relation to harmful effects for some non-target organisms

Contact Info

Product

Resources

About