scholarly journals Selection of Suitable Type of Nozzles for Development of Electrostatic Induction Nozzle

2021 ◽  
pp. 1-10
Author(s):  
B. Krishna Kanth ◽  
C. Ramana ◽  
S. Joseph Reddy ◽  
L. Eadukondalu ◽  
B. Ravindra Reddy
Keyword(s):  
Operating Pressure ◽  
Hollow Cone ◽  
Orifice Area ◽  
Nozzle Orifice ◽  
Electrostatic Induction ◽  
Leaf Surfaces ◽  
Droplet Sizes ◽  
Soil Bin ◽  
Selection Of ◽  
Orifice Opening

The electrostatic induction mechanism, which superimposes charges on pesticide spray droplets, creates an impact on deposition and wraparound effect on leaf surfaces Smaller droplets have a higher capability to charge accumulation over the surface of the droplet as compared with larger droplets. This paper studied the effect of nozzle type (flat fan, hollow cone, and full cone nozzle), orifice area (1 and 1.5 mm2), and operating pressure (3-5kg cm-2) on spray droplet characteristics on soil bin. Water-sensitive papers were analysed by image analysis software to get the droplet characteristics.   The smallest droplets of a hollow cone, flat fan, and full cone were 130, 142, and 279.76 µm respectively produced at 5kg cm-2 and orifice opening 1 mm2.  With an increase of pressure droplet size and relative span was decreased for all selective nozzle. From the selected nozzles, the lowest relative span of 0.89 was found with a hollow cone nozzle at 5 kg cm-2 pressure and orifice size of 1 mm2. Among all the selected nozzles hollow cone nozzle produced the smallest droplet sizes and lowest relative span for all selected parameters.

Development and Implementation of a Risk Based Prioritization Methodology for MAOP Reconfirmation of Gas Transmission Facilities

2016 ◽  
Author(s):  
Wytze Sloterdijk ◽  
Martin Hommes ◽  
Roelof Coster ◽  
Troy Rovella ◽  
Sarah Herbison
Keyword(s):  
Oil And Gas ◽  
Environmental Data ◽  
Operating Pressure ◽  
Line Pipe ◽  
Relative Significance ◽  
Coherent Risk ◽  
Relative Risks ◽  
Short And Long Term ◽  
Selection Of

As part of Pacific Gas and Electric Company’s (PG&E) on-going commitment to public safety, the company has begun a comprehensive engineering validation of its gas transmission facilities that will ultimately support the reconfirmation of maximum allowable operating pressure (MAOP) for these assets. In addition to 6,750 miles of line pipe, PG&E’s gas transmission system contains over 500 station facilities. Since this set of facilities is not only large but diverse, and the validation effort for these facilities is expected to be an extensive, multi-year process, a methodology for the prioritization of the facilities needed to be developed to facilitate planning of the process for the efficient mitigation of risk. As a result, DNV GL was retained to develop and implement a risk-based prioritization methodology to prioritize PG&E’s gas transmission facilities for the engineering validation and MAOP reconfirmation effort. Ultimately, a weighted multiple criteria decision analysis (MCDA) approach was selected and implemented to generate the prioritization. This MCDA approach consisted of the selection of relevant criteria (threats) and the weighting of these criteria according to their relative significance to PG&E’s facilities. Relevant criteria selected for inclusion in the analysis include factors that are important in order to assess both the short- and long-term integrity of the facility as a whole as well as the integrity of features for which design records cannot be located. The criteria selected encompass stable threats, time-dependent threats, as well as environmental impact. Enormous amounts of data related to design, operations, maintenance history and meteorological and seismic activity in addition to other environmental data were evaluated with this newly developed methodology to assess the relative risks of the facilities. Pilot field visits were performed to validate the selection of the various criteria and to confirm the outcome of the analysis. The novelty of this approach lies in the prioritization of facilities in a coherent risk-based manner. The described approach can be used by operators of oil and gas facilities, either upstream, midstream or downstream.

scholarly journals First Report of Powdery Mildew on Azalea Cv. Mollis (Rhododendron japonicum × R. molle) in Italy

Plant Disease ◽  
2002 ◽  
Vol 86 (3) ◽  
pp. 329-329
Author(s):  
A. Garibaldi ◽  
G. Gilardi ◽  
D. Bertetti ◽  
M. L. Gullino
Keyword(s):  
United Kingdom ◽  
Powdery Mildew ◽  
Northern Italy ◽  
First Report ◽  
The United Kingdom ◽  
Powdery Mildews ◽  
Initial Symptoms ◽  
Leaf Surfaces ◽  
Microscopy Examination ◽  
Selection Of

Rhododendron cultivation has a long history in northern Italy, where a wide selection of varieties and hybrids are grown. In summer 2001, a previously unknown powdery mildew was observed on azalea cv. Mollis (Rhododendron japonicum × R. molle) grown in several gardens in the province of Biella. Initial symptoms included chlorotic spots, followed by white fungal mycelia on both leaf surfaces. Eventually, infected leaves turned reddish and dropped prematurely. Fruit were also infected. On infected tissues, dark brown-to-black spherical cleistothecia developed, alone or in groups. The teleomorph was identified by light microscopy examination of cleistothecia. Cleistothecia measured 110 to 140 µm and were dark brown. They contained four to eight stalked or sessile asci that measured 35 to 45 µm × 40 to 55 µm, each containing six to eight ascospores. Ascospores were ellipsoid to ovoid and measured 12 to 18 µm × 20 to 25 µm. Cleistothecial characteristics were consistent with those described for Microsphaera azaleae but were different from those of the recently described species M. digitata reported in Belgium (1). The presence of conidia was rare in the specimens, so the anamorph could not be identified. To our knowledge, this is the first report of M. azaleae in Italy, but three outbreaks of powdery mildew on rhododendron were first reported in the United Kingdom on plants grown in glasshouses in the mid-1950s, 1969 and 1973 (1). Outdoors, powdery mildew was first reported on rhododendron in Europe in 1981. M. azaleae has been identified as the causal agent of rhododendron powdery mildew in the United Kingdom, Germany, and Switzerland (1). In most cases the disease is readily controlled by regular application of fungicides commonly used against powdery mildews of other crops. Reference: (1) A. J. Inman et al. J. Phytopathol. 148:17, 2000.

scholarly journals Spatial Distribution of Spray from a Solid Set Canopy Delivery System in a High-Density Apple Orchard Retrofitted with Modified Emitters

2021 ◽  
Vol 11 (2) ◽  
pp. 709
Author(s):  
Rakesh Ranjan ◽  
Rajeev Sinha ◽  
Lav R. Khot ◽  
Gwen-Alyn Hoheisel ◽  
Matthew Grieshop ◽  
...  
Keyword(s):  
Spray Deposition ◽  
Delivery Systems ◽  
Apple Orchard ◽  
High Density ◽  
Superior Performance ◽  
Hollow Cone ◽  
Perennial Crop ◽  
Laboratory Assessment ◽  
Leaf Surfaces ◽  
Tracer Solution

Solid Set Canopy Delivery Systems (SSCDS) are fixed agrochemical delivery systems composed of a network of micro-sprayers/nozzles distributed in perennial crop canopies. A previous SSCDS design composed of a 3-tier configuration using hollow cone sprayer nozzles has been shown to provide excellent coverage and deposition in high-density apple orchards. However, the hollow cone nozzles substantially increases the initial system installation costs. This study evaluated the effect of irrigation micro-emitters replacement on spray deposition, coverage and off-target drift. A micro-emitter used in greenhouse irrigation systems was duly modified to enhance its applicability with SSCDS. After laboratory assessment and optimization of the micro-emitters, a replicated field study was conducted to compare 3-tier SSCDS configured with either of modified irrigation micro-emitters or traditional hollow cone nozzles. Canopy deposition and off target drift were evaluated using a 500 ppm fluorescent tracer solution sprayed by the field installed systems and captured on mylar collectors. Spray coverage was evaluated using water sensitive papers. The overall canopy deposition and coverage for treatment configured with modified irrigation micro-emitters (955.5 ± 153.9 [mean ± standard error of mean] ng cm−2 and 22.7 ± 2.6%, respectively) were numerically higher than the hollow cone nozzles (746.2 ± 104.7 ng cm−2 and 19.0 ± 2.8%, respectively). Moreover, modified irrigation micro-emitter SSCDS had improved spray uniformity in the canopy foliage and on either side of leaf surfaces compared to a hollow cone nozzle. Ground and aerial spray losses, quantified as deposition, were numerically lower for the modified irrigation micro-emitter (121.8 ± 43.4 ng cm−2 and 0.7 ± 0.1 ng cm−2, respectively) compared to the traditional hollow cone nozzle (447.4 ± 190.9 ng cm−2 and 3.2 ± 0.4 ng cm−2, respectively). Overall, the modified irrigation micro-emitter provided similar or superior performance to the traditional hollow cone nozzle with an estimated 12 times reduction in system installation cost.

Droplet Size Spectrum, Activation Pressure, and Flow Rate Discharged from PWM Flat-Fan Nozzles

2021 ◽  
Vol 64 (1) ◽  
pp. 313-325
Author(s):  
Zhiming Wei ◽  
Heping Zhu ◽  
Zhihong Zhang ◽  
Ramón Salcedo ◽  
Degang Duan
Keyword(s):  
Droplet Size ◽  
Duty Cycle ◽  
Solenoid Valve ◽  
Variable Rate ◽  
Size Distributions ◽  
Flow Rates ◽  
Nozzle Orifice ◽  
Duty Cycles ◽  
Droplet Sizes ◽  
Droplet Size Distributions

HighlightsDroplet sizes, activation pressures acting on nozzle orifices, and flow rates were investigated.Droplet sizes varied with duty cycles, nozzle orifice sizes, and PWM solenoid valve manufacturers.Activation pressures decreased as duty cycles decreased and increased as nozzle orifice sizes decreased.Flow rates increased with increases in both duty cycles and nozzle orifice sizes.Abstract. Pulse width modulated (PWM) spray systems can produce variable spray rates for precision applications of pesticide and fertilizer; however, there are also concerns over their spray performance stability. Droplet size distributions, activation pressures acting on nozzle orifices, and flow rates discharged from nozzles were investigated for test combinations of ten PWM duty cycles (10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 100%), six flat-fan nozzles with different orifice sizes (XR8001, XR8002, XR8003, XR8004, XR8005, and XR8006), and two PWM solenoid valves from two different manufacturers. Test results showed that the droplet size distribution, activation pressure, and flow rate varied with the duty cycle, nozzle orifice size, and PWM solenoid valve source. For XR8001 and XR8002 nozzles, droplet sizes did not vary significantly with all duty cycles from 10% to 100%. To obtain relatively consistent droplet size distributions, XR8003 and XR8004 nozzles required PWM duty cycles of at least 20%, while XR8005 and XR8006 nozzles required duty cycles of 30% or greater. The activation pressure directly on nozzle orifices increased as the duty cycle increased but decreased as the nozzle orifice size increased. In addition, the same nozzles coupled with PWM solenoid valves from two different manufacturers discharged different flow rates for the same duty cycle in the range of 10% to 90%. Therefore, careful selection of PWM solenoid valves for different orifice nozzles operated at different duty cycles was necessary to achieve consistent variable-rate spray performances. Keywords: Droplet diameter, Variable rate, PWM solenoid valve, Pesticide, Fertilizer, Precision farming.

Characteristics of Hollow Cone Swirl Spray at Various Nozzle Orifice Diameters

2012 ◽  
Vol 58 (2) ◽  
Author(s):  
A. Hussein ◽  
M. Hafiz ◽  
H. Rashid ◽  
A. Halim ◽  
W. Wisnoe ◽  
...  
Keyword(s):  
Discharge Coefficient ◽  
Cone Angle ◽  
Injection Pressure ◽  
Orifice Diameter ◽  
Hollow Cone ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Nozzle Orifice ◽  
Breakup Length

An experimental work to investigate the swirl spray characteristics that emanates from hollow–cone and solid–cone spray simplex atomizers is presented. Main objective of the research is to investigate the spray characteristics, i.e. spray breakup length, discharge coefficient and spray cone angle at different nozzle orifice diameter and injection pressure. Discharge coefficient is almost uninfluenced by the operating Reynolds number. This test also reveals that both breakup length and spray cone angle increases as orifice diameter is increased. Higher injection pressure leads to shorter breakup length and wider spray cone angle.

Rotary Disk Atomization

1988 ◽  
Vol 2 (1) ◽  
pp. 106-113 ◽  
Author(s):  
Maurice R. Gebhardt
Keyword(s):  
Low Flow ◽  
Hollow Cone ◽  
Downward Movement ◽  
Droplet Impingement ◽  
Rotary Disk ◽  
Droplet Sizes ◽  
Continued Use ◽  
Droplet Trajectory ◽  
The Cost ◽  
Impingement Velocity

In the late 1930s, European engineers discovered that, for very low flow rates, rotary disk atomizers produced a more definable range of droplet sizes than hydraulic atomizers. In the late 1970s, a cup-like spinning atomizer was developed to apply herbicides at low and ultra-low volumes. Rotary atomizers distribute droplets in a pattern similar to hollow cone nozzles. The droplet trajectory could affect deposits adversely since droplets released horizontally are exposed to wind and other environmental effects longer than hydraulic spray nozzles. Propellers and fans were used to enhance downward movement of droplets without considering that droplet impingement velocity was critical for efficient deposition. In the early 1980s, rotary atomizers were promoted to reduce herbicide rates, but the claims were products of unconfirmed testing. Herbicide efficacy in confirmed research was not influenced by application with the rotary atomizer, but lower carrier rates reduced the amount of water handled during the spraying operation. The cost of the atomizer, more maintenance, and greater care during operation with no decrease in herbicide rates discourage continued use.

scholarly journals Control of Tomato Pinworm (Tpw) with Abamectin in Staked Tomato, 1996

1997 ◽  
Vol 22 (1) ◽  
pp. 189-189
Author(s):  
P. A. Stansly ◽  
J. M. Conner
Keyword(s):  
Disease Control ◽  
Drip Irrigation ◽  
Rating Scale ◽  
Insect Damage ◽  
Operating Pressure ◽  
Hollow Cone ◽  
Commercial Plant ◽  
Entire Plant ◽  
Marketable Fruit ◽  
Tomato Pinworm

Abstract Tomato seedings “Agriset” from a commercial plant house were transplanted on 7 Mar 96, 18 in. between plants, into raised beds 32 in. wide on 6-ft centers covered with black polyethylene film mulch. A dry bottom mix of 50 lbs N, 160 lbs P and 80 lbs K per acre had been placed at the bottom of the beds and an additional 3.25 lbs per acre N and K were fertigated 3 times a week by drip irrigation. The plants were sprayed weekly with an alternating combination of Maneb 80 WP at 1.5 lb/acre plus Kocide 101 at 2 lb/acre and Bravo 720 at 2 pt/acre for disease control. Dipel was added to the disease control sprays when needed at a rate of 1 lb product/acre. Two wing-type traps from AgriSense containing TPW pheromones were set out on 23 Apr. 15 feet to the east and west of the trial area to monitor moth activity. Mean number of moths captured rose from 1.4 per night on 26 Apr to a peak of 33.6 on 10 May, later declining to 8.0 on 20 May. Plots, 30 ft long and 2 rows, wide were assigned one of 3 treatments in a CRB design with 4 replications. All treatments were sprayed weekly from 1 May to 15 May for three applications at 69 gpa using a high clearance sprayer with 2 booms of 3 Yellow Albuz hollow cone nozzles each for a total of 6 per row and operating pressure of 200 psi. Plants (10 per row or 20 total) were evaluated before treatment on 30 Apr and again on 6 and 13 May by counting live and dead miners. Damage for the entire plant was assessed on a rating scale of 1-6: “1” = no apparent damage; “2” = 0-1% of leaflets damaged; “3” = 2-5% damaged; “4” = 6-10% damaged; “5” = 11-30% damaged; and “6” = >30% damaged. Fruit was harvested 21 May from 20 plants per plot and the marketable fruit graded on a commercial table with weights and numbers recorded. Unmarketable fruit was separated into categories of TPW damage, other insect damage and damage due to disease.

scholarly journals Assessment of pesticide application quality with a manual sprayer in spinach

2016 ◽  
Vol 34 (3) ◽  
pp. 346-354 ◽  
Author(s):  
Juan David Sesquile ◽  
Bernardo Castillo
Keyword(s):  
Spinacia Oleracea ◽  
Tracer Technique ◽  
Pesticide Application ◽  
Hollow Cone ◽  
Fluorescent Tracer ◽  
Spinacia Oleracea L ◽  
Leaf Surfaces ◽  
Application Techniques ◽  
Flat Fan Nozzle

Two experiments were conducted to evaluate the performance of three hollow cone nozzles (TeeJet® TX 800050 VK, TeeJet® TXA 8004 VK and TX-Royal Condor®) and one flat fan nozzle (TeeJet® XR 8004 VS) with two manual application techniques on a crop of spinach (Spinacia oleracea L.). In order to assess the quality ofthe application of pesticides, WSP (water sensitive paper) collectors and fluorescent tracer Tinopal® CBS-X were used. In one ofthe trials, percentage of tracer retained by the leaf surfaces was also determined. In this study, and based on the methodology of collectors, it was observed that the technique of applying two passes with the TX-Royal Condor® nozzle could be recommended for the application of pesticides with a hand-operated sprayer in the spinach crop. However, this was not corroborated by the fluorescent tracer technique.

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