The effect of surface orientation on spray retention

Massinon, Mathieu; Boukhalfa, Hassina dite Hafida; Lebeau, Frédéric

doi:10.1007/s11119-013-9345-2

Cited by 28 publications

(29 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Likewise, Massinon et al (2014) obtained similar results for water and surfactant mixtures on PTFE and blackgrass leaves of various orientations. Rather than using Weber numbers of transition to delineate adhesionbounce and bounce-shatter zones, they reported impact outcome probability as a function of eleven energy classes, where each class boundary corresponds to a constant Weber number.…”

Section: Introductionsupporting

confidence: 52%

Impaction of spray droplets on leaves: influence of formulation and leaf character on shatter, bounce and adhesion

et al. 2015

View full text Add to dashboard Cite

This paper combines experimental data with simple mathematical models to investigate the influence of spray formulation type and leaf character (wettability) on shatter, bounce and adhesion of droplets impacting with cotton, rice and wheat leaves. Impaction criteria that allow for different angles of the leaf surface and the droplet impact trajectory are presented; their predictions are based on whether combinations of droplet size and velocity lie above or below bounce and shatter boundaries. In the experimental component, real leaves are used, with all their inherent natural variability. Further, commercial agricultural spray nozzles are employed, resulting in a range of droplet characteristics. Given this natural variability, there is broad agreement between the data and predictions. As predicted, the shatter of droplets was found to increase as droplet size and velocity increased, and the surface became harder to wet. Bouncing of droplets occurred most frequently on hard to wet surfaces with high surface tension mixtures. On the other hand, a number of small droplets with low impact velocity were observed to bounce when predicted to lie well within the adhering regime. We believe this discrepancy between the predic-G.J. Dorr (joint first author), tions and experimental data could be due to air layer effects that were not taken into account in the current bounce equations. Other discrepancies between experiment and theory are thought to be due to the current assumption of a dry impact surface, whereas, in practice, the leaf surfaces became increasingly covered with fluid throughout the spray test runs. arXiv:1506.04258v1 [physics.flu-dyn]

show abstract

Section: Introductionsupporting

confidence: 52%

Impaction of spray droplets on leaves: influence of formulation and leaf character on shatter, bounce and adhesion

et al. 2015

View full text Add to dashboard Cite

show abstract

“…An important factor affecting the effectiveness of the application of herbicides is to reduce the rebounding of droplets in the spray liquid. This depends on the dynamic surface tension [42]. The low level of dynamic surface tension causes uniformly low surface tension to occur at the interface of air, liquid and solid.…”

Section: Discussionmentioning

confidence: 99%

Effect of Adjuvants and pH Adjuster on the Efficacy of Sulcotrione Herbicide

et al. 2020

View full text Add to dashboard Cite

The effectiveness of herbicides is affected by the pH of the spray liquid. The use of adjuvants can mitigate the negative effect of pH, and it also allows for a reduction in herbicide doses while maintaining high efficiency. Greenhouse studies were performed to evaluate the efficacy of the herbicide sulcotrione (HRAC F2), against barnyardgrass, at full or reduced doses with adjuvants, and a modified pH of the solutions. The contact angle and surface tension of liquid spray drops, as well as the shear viscosity of individual solutions, were also tested. Results indicated that at a low pH of the spray liquid (4), the use of a reduced dose of sulcotrione with adjuvant based on methylated rapeseed oil can increase the effectiveness of barnyardgrass control to the same level as at the full dose of herbicide. The use of adjuvants contributed to the reduction in the contact angle and the surface tension of liquid spray droplets. No significant differences in shear viscosity were observed for individual solutions.

show abstract

“…Understanding the physics at the droplet scale could help in maximizing the retention of spray droplets on plant surfaces, and improve the performance of spraying systems. 3,12 Better knowledge of the impact dynamics of the droplets on plant surfaces is the basis for the development of precision spraying systems.…”

Section: Relevance Of This Study For Improving the Performance Of Sprmentioning

confidence: 99%

“…1,2 During application of crop protection chemicals, it is important to optimize the amount and uniformity of the on-target deposition while avoiding exceeding residue levels and minimizing run-off and drift with consequent environmental risks. [3][4][5] During irrigation, the amount of liquid that is intercepted by the plant canopy affects the performance of irrigation systems. Canopy interception is considered as one of the causes of water loss, and a reduction in the plant transpiration rate due to canopy interception was also reported.…”

Section: Introductionmentioning

confidence: 99%

Predicting the dynamic impact behaviour of spray droplets on flat plant surfaces

Delele

Nuyttens²,

Duga

et al. 2016

Soft Matter

View full text Add to dashboard Cite

The dynamic impact behaviour of water droplets on plant surfaces was investigated based on a multiphase computational fluid dynamics (CFD) model. The study was conducted using the Volume Of Fluid (VOF) approach. The static contact angle of water droplets on leaf surfaces of different plants (apple, pear, leek and cabbage) was measured and found to vary between 54.9 and 138.2°. Impact experiments were conducted by monitoring the flow and impact characteristics of water droplets on leaves in still air with a high speed camera. Droplets were generated by an agricultural flat fan spray nozzle moving across the leaf at constant speed. The nozzle produced droplets with diameters ranging from 20.6 up to 550.8 μm, and droplet velocity values near the impact between 0.03 and 13.2 m s(-1). The CFD model was capable of predicting the observed dynamic impact behaviour of droplets on the plant surfaces. The fate of the droplets after the impact process for adhesion, bouncing or splashing was accurately predicted for Weber numbers (We) in the range of 0.007 to 1096 and droplet Reynolds numbers (Re) between 5 to 8000. The process was highly dependent on the surface and droplet flow characteristics during the impact. Combinations of We, Re and Ohnesorge (Oh) numbers defined the droplet maximum spread factor, the number of secondary droplets generated as a result of the splashing process and the transition between the different impact outcomes. These criteria can then be used in field scale spray deposition and drift models to better understand agricultural spray operations.

show abstract

The effect of surface orientation on spray retention

Cited by 28 publications

References 40 publications

Impaction of spray droplets on leaves: influence of formulation and leaf character on shatter, bounce and adhesion

Impaction of spray droplets on leaves: influence of formulation and leaf character on shatter, bounce and adhesion

Effect of Adjuvants and pH Adjuster on the Efficacy of Sulcotrione Herbicide

Predicting the dynamic impact behaviour of spray droplets on flat plant surfaces

Contact Info

Product

Resources

About