scholarly journals Advances in developing a new test method to assess spray drift potential from air blast sprayers

2017 ◽  
Vol 15 (3) ◽  
pp. e0207 ◽  
Author(s):  
Marco Grella ◽  
Emilio Gil ◽  
Paolo Balsari ◽  
Paolo Marucco ◽  
Montserrat Gallart

Drift is one of the most important issues to consider for realising sustainable pesticide sprays. This study proposes and tests an alternative methodology for quantifying the drift potential (DP) of air blast sprayers, trying to avoid the difficulties faced in conducting field trials according to the standard protocol (ISO 22866:2005). For this purpose, an ad hoc test bench designed for DP comparative measurements was used. The proposed methodology was evaluated in terms of robustness, repetitiveness and coherence by arranging a series of trials at two laboratories. Representative orchard and vineyard air blast sprayers in eight configurations (combination of two forward speeds, two air fan flow rates, and two nozzle types) were tested. The test bench was placed perpendicular to the spray track to collect the fraction of spray liquid remaining in the air after the spray process and potentially susceptible to drift out of the treated area. Downwind spray deposition curves were obtained and a new approach was proposed to calculate an index value of the DP estimation that could allow the differences among the tested configurations to be described. Results indicated that forward speed of 1.67 m/s allows better discrimination among configurations tested. Highest DP reduction, over 87.5%, was achieved using the TVI nozzles in combination with low air fan flow rate in both laboratories; conversely, the highest DP value was obtained with the ATR nozzles in combination with high air fan flow rate. Although the proposed method shows a promising potential to evaluate drift potential of different sprayer types and nozzles types used for bush and tree crops further research and tests are necessary to improve and validate this method.

2014 ◽  
Vol 42 (1) ◽  
pp. 2-15
Author(s):  
Johannes Gültlinger ◽  
Frank Gauterin ◽  
Christian Brandau ◽  
Jan Schlittenhard ◽  
Burkhard Wies

ABSTRACT The use of studded tires has been a subject of controversy from the time they came into market. While studded tires contribute to traffic safety under severe winter conditions by increasing tire friction on icy roads, they also cause damage to the road surface when running on bare roads. Consequently, one of the main challenges in studded tire development is to reduce road wear while still ensuring a good grip on ice. Therefore, a research project was initiated to gain understanding about the mechanisms and influencing parameters involved in road wear by studded tires. A test method using the institute's internal drum test bench was developed. Furthermore, mechanisms causing road wear by studded tires were derived from basic analytical models. These mechanisms were used to identify the main parameters influencing road wear by studded tires. Using experimental results obtained with the test method developed, the expected influences were verified. Vehicle driving speed and stud mass were found to be major factors influencing road wear. This can be explained by the stud impact as a dominant mechanism. By means of the test method presented, quantified and comparable data for road wear caused by studded tires under controllable conditions can be obtained. The mechanisms allow predicting the influence of tire construction and variable operating conditions on road wear.


Author(s):  
V.N. Petrov ◽  
◽  
F.M. Galimov ◽  
O.K. Borisova ◽  
S.V. Petrov ◽  
...  
Keyword(s):  

2017 ◽  
Vol 9 (2) ◽  
pp. 168781401668726 ◽  
Author(s):  
Fan Yang ◽  
Gangyan Li ◽  
Dawei Hu ◽  
Toshiharu Kagawa

In this study, we proposed a method for calculating the sonic conductance of a short-tube orifice. First, we derived a formula for calculating the sonic conductance based on a continuity equation, a momentum equation and the definition of flow-rate characteristics. The flow-rate characteristics of different orifices were then measured using the upstream constant-pressure test method in ISO 6358. Based on these test data, the theoretical formula was simplified using the least squares fitting method, the accuracy of which was verified experimentally. Finally, the effects of the diameter ratio, the length-to-diameter ratio and the critical pressure ratio were analysed with reference to engineering applications, and a simplified formula was derived. We conclude that the influence of the diameter ratio is greater than that of the length-to-diameter ratio. When the length-to-diameter ratio is <5, its effect can be neglected. The critical pressure ratio has little effect on the sonic conductance of a short-tube orifice, and it can be set to 0.5 when calculating the sonic conductance in engineering applications. The formula proposed in this study is highly accurate with a mean error of <3%.


2021 ◽  
Vol 3 (2) ◽  
pp. 276-285
Author(s):  
Brigita Suzanna ◽  
Irwan Lie Keng Wong ◽  
Monika Datu Mirring Palinggi

The purpose of this research is to determine the physical properties of clay soil and to analyze the effect of adding coconut shell charcoal ash to the clay soil. The soil samples used in this study came from Tanralili District, Maros Regency, two sample points were taken and the variations in the levels of addition of coconut shell charcoal ash is 0%, 4%, 6%, 8%, 10%. The test method used refers to ASTM (American Society for Testing Materials). The tests carried out were testing the physical properties of the soil in the form of moisture content, specific gravity, Atterberg boundaries, filter analysis, and hydrometer analysis, then a compaction test was carried out to determine the maximum soil density. The results of the test obtained a moisture content value of 28.811%, a specific gravity of 2.58 g / cm3 so that it is classified as organic clay. As well as the plasticity index value of 9.926% with moderate plasticity from the 7% -17% interval. Then from the test results of soil compaction testing with the addition of coconut shell ash, the dry density (gdry) equal to 0.862, 0.886, 0.914, 0.943, 0.962, this means that the soil sample experienced an increase in dry density (gdry) of 11.60%. From the research results it can be concluded that the addition of coconut shell charcoal ash can increase the value of soil dry density so that it can be used to increase the value of the carrying capacity of clay soil.


Irriga ◽  
2009 ◽  
Vol 14 (1) ◽  
pp. 41-53 ◽  
Author(s):  
Giuliani Do Prado ◽  
Alberto Colombo

COMPOSIÇÃO DE PERFIS RADIAIS DE DISTRIBUIÇÃO DE ÁGUA DE ASPERSORES  Giuliani do Prado; Alberto ColomboDepartamento de Engenharia, Universidade Federal de Lavras, Lavras, MG, [email protected]  1 RESUMO Este trabalho descreve um procedimento de composição do perfil radial de aspersores que operam com dois bocais. Foram determinados na bancada de ensaios de aspersores da Universidade Federal de Lavras, em Lavras/MG, os valores de vazão e perfil radial do aspersor PLONA-RL250 operando, individualmente, com os bocais principais 14 e28 mme com os bocais auxiliares 5, 6 e7 mm, e operando, nas diferentes seis combinações de bocal auxiliar e principal do aspersor, sob cinco pressões de serviço (292, 392, 490, 588 e 696 kPa). No processo de composição do perfil radial realizado, ajustando a vazão dos bocais auxiliar e principal, operando individualmente, a vazão do aspersor operando com o conjunto de bocais auxiliar e principal, verificou-se um coeficiente de determinação médio de 88,57% entre as intensidades de precipitação adimensionais dos perfis radiais compostos com os perfis radiais do conjunto. Na relação linear, ajustada, entre os valores de uniformidade de equipamentos autopropelidos de irrigação, obtidos com os perfis radiais compostos e do conjunto, a inclinação da reta foi igual a 44°12’com um erro relativo médio de 2,34%. Estes resultados mostram que o procedimento de composição do perfil radial de aspersores não influencia, de maneira significativa, na uniformidade de aplicação de água de aspersores. UNITERMOS: bocais do aspersor, vazão do aspersor, uniformidade de irrigação.  PRADO, G. DO; COLOMBO, A. SPRINKLER WATER DISTRIBUTION COMPOSITIONS  2 ABSTRACT This paper described a procedure to compose a sprinkler pattern for a sprinkler that operates with two nozzles. To compose the pattern, discharge values and patterns of the PLONA-RL250 sprinkler were determined at the sprinkler test bench of the Universidade Federal de Lavras, in Lavras/MG. The tests were conducted with all possible combinations using 14mm and28 mmmain nozzles and the 5, 6 and7 mmauxiliary nozzles as well as with each nozzle functioning individually. Five working pressures (294, 392, 490, 588 and 686 kPa) were used for each nozzle configuration. In the pattern composition process, by adjusting the main and auxiliary nozzle discharges operating individually, and by adjusting  the sprinkler discharge operating with the corresponding pair of main and auxiliary nozzles, it was verified that the average determination coefficient was 88.57% between the dimensionless water application rate of the composed and pair patterns. In the adjusted linear relation, between the uniformity values of a travel irrigation machine obtained from the composed and pair patterns, the inclination was 44° 12' with an average relative error of 2.34%. These results show that the procedure to compose a sprinkler pattern for sprinklers does not influence significantly the water application uniformity of sprinklers. KEY WORDS: sprinkler nozzles, sprinkler flow rate, irrigation uniformity


Author(s):  
Christian von Grabe ◽  
David van Bebber ◽  
Hubertus Murrenhoff

The development of combustion engines with direct injection requires a comprehensive knowledge of the in cylinder combustion process as well as the used high pressure injection system. One main characteristic of injection systems is their mass flow over time behavior. For prevalent diesel and gasoline injection valves (injectors) fully developed simulation models as well as test benches are available to analyze the injection process. Besides the established engines a trend towards compressed natural gas (CNG) engines in passenger cars is recognized. Due to the small injection duration of a few milliseconds, the flow rate measurement is particularly challenging and requires highly dynamic measuring. The existing test benches are designed and optimized for liquid fuels and are only partly suitable for the evaluation of gaseous fuels such as CNG. A typical test method is to inject fuel into a long tube in which a pressure wave propagates. Based on the pressure signal the mass flow of the injected fuel is approximated. For gaseous fuels the correlation of mass flow and pressure propagation is only known for specific test cases and therefore the method is not directly applicable to gaseous fuels. This paper presents a newly designed measurement device to evaluate the mass flow rate as well as the injector needle displacement during an injection process of gaseous fuels. The test bench is designed to operate in a fully equipped injection system including gas lines, common rail and injection valves, to also investigate the interaction of the individual system components. The design is based on a closed test chamber in which the pressure rises during the injection. To overcome the influence of propagating pressure waves inside the chamber on the measurement, different chamber designs are evaluated. An optimized design, separating the chamber into two volumes which are connected by a damping sleeve, is presented. The injection itself is carried out in a first volume and the measurement is conducted in a second damped volume. Based on the measured pressure the mass flow rate through the injection valve is approximated, utilizing the equations of thermodynamics.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Umar Khan ◽  
Sonia Biccai ◽  
Conor S. Boland ◽  
Jonathan N. Coleman

AbstractThe development of low-cost ultrafiltration membranes with relatively high flow rate and selectivity is an important goal which could improve access to clean water in the developing world. Here we demonstrate a method to infuse mixtures of graphene nanosheets and Teflon nanoparticles into ultra-cheap glass fibre membranes. Annealing the resultant composites leads to coalescence of the Teflon, resulting in very stable membranes with significantly enhanced mechanical properties. In filtration tests, while adding ~ 10 wt% graphene/Teflon to the glass fibre membrane decreased the flow rate by × 100, the selectivity improved by × 103 compared to the neat glass fibre membrane. This combination of selectively and flow rate was significantly better than any commercial membrane tested under similar circumstances. We found these membranes could remove > 99.99% of 25–250 nm diameter SiC nanoparticles dispersed in ethanol, transmitting only particles with diameters < 40 nm, performance which is superior to commercial alumina membranes. Field trials on dirty canal water showed these composite membranes to remove aluminium to a level × 10 below the EU limit for drinking water and reduce iron and bacteria contents to below detectable levels.


2008 ◽  
Vol 52 (3) ◽  
pp. 739-764 ◽  
Author(s):  
Hongtao Tian ◽  
Sanjay K. Bose ◽  
Choi Look Law ◽  
Wendong Xiao

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