Hollow Cone Nozzles Research Articles

F55

This test was conducted in a commercial cotton field grown near Lubbock, TX. The field was on 40-inch rows, and was irrigated using furrow irrigation. Plots were 4-rows wide × 50 ft in length. Insecticides were applied with a CO2 pressurized hand-boom sprayer calibrated to deliver 10 gpa through TX-6 hollow cone nozzles (2 per row) at 40 psi. Insecticides were applied to all four rows of each plot. Treatments were evaluated by collecting 5 or 10, mid canopy leaves per plot and returning these to the laboratory where the mites were removed onto a liquid detergent coated glass plate with a mite brush. Mite eggs, larvae and adults were counted from the entire glass plate. Data were analyzed using ANOVA and means were separated using an F-protected LSD (P ≤ 0.05).

Improved quality of fungicide deposition and coverage of potato leaves using flat fan air-injector nozzle IDK

The aim of our experiment was to improve fungicide spray deposition and coverage of potato leaves by using air-injector nozzle types. We used two standard nozzle types - a flat fan nozzle ST and a hollow cone nozzle TR, as well as a couple of air-injector nozzle types - an air-injector compact nozzle IDK and a symmetric double flat fan air-injector nozzle TWIN (with a 30 ° forward and a 30 ° backward spray jet angle). Water-sensitive paper was placed on the upper, middle and lower part of the plant in order to determine the quality of fungicide deposition and the ability of droplets to penetrate lower parts of the plant. When using the air-injector compact nozzle IDK, potato leaves were covered well at all three levels of the plant. The use of the above-mentioned nozzle resulted in the lowest reduction in coverage value and droplet impression area from the top towards the lowest part of the plant. Furthermore, the nozzle created large enough droplets with sufficient mass and speed to penetrate the dense canopy all the way to the lowest part of the plant. When using the symmetric double flat fan air-injector nozzle TWIN, the angle of both spray jets was excessively wide in order for the droplets to reach the lower part of the plant despite a very large droplet impression area. The use of both standard nozzle types resulted in a poor spray mixture coverage of the middle and lower part of the plant. This predominantly occurred due to insufficient droplet size and the subsequent lack of kinetic energy. Results show that the use of a newer air-injector compact nozzle IDK improves the deposition and coverage of potato leaves with spray mixture.

A vertical spray boom application technique for conical bay laurel (Laurus nobilis) plants

Bay laurel, a commercially grown evergreen ornamental plant and economically important for Flanders (Belgium), is very susceptible to pests. Pest management usually consists of spraying pesticides using handheld application techniques which are labour-intensive, involve a high risk for operator exposure, and provide only suboptimal biological control. One alternative, a vertical spray boom, was evaluated in a bay laurel crop pruned into a conical shape. Different spray boom configurations were by attaching water-sensitive papers to a model that emulated the size and shape of the trees. The optimal nozzle type was determined by deposition measurements in an actual laurel crop. Three application rates were tested, 2450, 4900 and 7200 L ha−1 of ground surface. The most efficient spray application technique was found to be an extended range flat fan, an air included flat fan or a hollow cone nozzle, all at 4900 L ha−1 resulting in the highest relative spray deposits and the most uniform spray distribution in the canopy.

Continuous formation of submicron energetic particles by the flash-evaporation technique

The flash-evaporation process is a promising technique in the domain of the large scale production of ultra-fine particles. By means of a common hollow cone nozzle, superheated solutions are steadily sprayed into an evacuated atomization chamber where the solvent evaporates and the solute crystallizes. Separation of the particles from the aerosol is achieved by axial cyclones in a parallel arrangement. A continuous operating pilot plant, from the size of a desk, already produces up to 3g/h of a product with a particle size below 500nm. The thermodynamic properties of this process are advantageous for the nanostructuration of various organic compounds such as primary and secondary explosives as well as energetic composites.

Efeito de pontas e pressões de pulverização na deriva de glyphosate + 2,4-D em condições de campo

The aim of the work was to evaluate the effect of nozzles and pressures on the spray drift from glyphosate + 2,4-D. The nozzles designs and the respective studied pressures were: XR 11002 (150 and 300 kPa), DG 11002 (300 kPa), TT 11002 (300 kPa), AI 11002 (300 kPa) and TXVS-10 (400 kPa). Nylon strings outside the application area (1, 5, 10, 20, 50, 100 and 200 m distance) with four replications and six foam cylinders placed on the boom of the sprayer were used to collect the spray drift. Salt tracers were added in the spray solutions to quantify the deposits of each treatment by spectrophotometer. Herbicides were less and more susceptible to drift with the flat fan nozzle with pre-orifice and air induction (AI) and the hollow cone nozzle (TX), respectively. The nozzle selection and the reduction on the spray pressures may be used to decrease drift.

Modeling and Simulation of Evaporating Spray Flows with Coalescence in an Eulerian Framework

AbstractThe study concerns the modeling and simulation of gas‐droplet and droplet‐droplet interactions on spray dynamics and droplet size distribution in turbulent spray flows where the spray is described in an Eulerian framework. The primary focus is to develop a suitable mathematical model that can describe the underlying physics including the polydispersion of the spray, evaporation, drag, coalescence, and interaction with the convective gas flow. This is achieved by applying the direct quadrature method of moments, which is extended to account for evaporation, drag force and coalescence by implementing well‐established standard models available in literature. The model is developed and formulated in three‐dimensional physical space, whereas the computations are carried out in a one‐dimensional geometric configuration since the reference experimental setup is only one‐dimensional. A water spray carried by nitrogen was injected through a hollow cone nozzle into a cylindrical spray chamber. The results reveal that evaporation and coalescence have a significant effect on the droplet size distribution whereas the droplet velocity is influenced by drag force as anticipated. Computational and experimental results agree very well when coalescence is considered.

CHARACTERIZATION OF HYDRAULIC NOZZLES FOR DROPLET SIZE AND SPRAY COVERAGE

Spray coverage specifications for commercially available nozzles could help applicators determine the optimal nozzles for effective control of insects, diseases, and weeds. Spray coverage and deposit density from seven types of nozzles at three different flow rates (0.76, 1.14, and 2.27 L min−1) and two target positions (0.50 and 0.70 m below the nozzle) were evaluated with water-sensitive papers (WSP) as targets under controlled environmental conditions. These nozzles included 80°and 110° conventional flat-fan nozzles, air induction flat-fan nozzles with the air intake hole either opened or sealed, hollow-cone nozzles, turbo jet nozzles, and twin-jet fan pattern nozzles. Spray coverage (percent area of a WSP covered with spray depositions) increased as flow rate increased for all nozzles. The hollow-cone nozzles had the highest coverage at both target positions while air induction nozzles had the lowest coverage.With the same flow rate, the 80° nozzles had higher spray coverage than 110° nozzles. Nozzles producing coarse spray had the lower spray coverage than nozzles producing fine and medium sprays. The 80° and 110° flat-fan nozzles at lower-than-specified operating pressures produced spray as coarse as that from the air induction nozzles with similar coverage. There was no significant difference in spray coverage between the same air induction nozzles whether the two air intake holes were opened or sealed. Spray coverage on targets at the 0.50 m position was greater than that at the 0.70 m position. Therefore, careful selection of nozzles could provide comparable performance for economical and effective spray coverage with optimal flow rates and operating pressures.

Development of Experimental Pulsed SprayDevice for Spot Application

An experimental pulsed spray device was developed and studies were conducted on targeted spraying and spray application rate. The discharge of carrier fluid and chemical were measured at different set of pressures by using two types of hollow cone nozzles viz BAN nozzle and NMD hollow cone nozzle. Carrier fluid pressure was maintained from 0.05 to 0.2 MPa and the chemical tank pressure was varied from 0.05 to 0.3 MPa. The important characteristics of pulsed spray system were evaluated at different pressures and it was found that, at pressure 1 MPa the VMD was medium spray and at pressure 0.15 to 0.4 MPa VMD was fine spray. It is noticed that the applied volume per unit area is uniform when the pressure is within 0.15 to 0.4 MPa. The results showed that the quantity of chemical applied per pulse varied between 0.4 to 1.2 ml per pulse for different operating pressures and target widths. From the prediction equation, the quantity of chemical applied over the plant was calculated as 2.6 ml when the area of the plant is 78 cm2 . Hence the application rate of chemical was estimated as 0.33 ml/cm 2.

Air-Assistance in Spray Booms which have Different Spray Volumes and Nozzle Types for Chemically Controlling Spodoptera Frugiperda on Corn

The study aimed to evaluate the performance of air assistance in spray booms using different types of nozzles and spray volumes. We took into account spray deposits, fall armyworm control and crop corn performance in a narrow row cropping system. The experiment was carried out at the experimental area of Sao Paulo State University, Botucatu/SP, Brazil, during the 2008/2009 ag- ricultural season, in randomized blocks with a factorial scheme (2x2+1) and four replications. Two spray nozzles (flat fan nozzle and hollow cone nozzle) were tested, combined with two air assistance levels in the spray boom (with and without air assistance) and a treatment control. In the experimental spraying, Spinosad insecticide was sprayed in amounts of 48 g active substance (a.s.)/ha. The air assistance in the spray boom increased the spray deposits in the V 4 growth stage of the corn plants. Moreover, the application of this technology showed higher efficiency on fall armyworm control, reaching a 100% level 15 days after spraying, in the V 10 growth stage of the plants. The hollow cone nozzle increased the spray deposit level on the corn plants compared with the flat fan nozzle, at growth stage V 4 . However, the flat fan nozzle, combined with air assistance technology, was more effective for controlling fall army- worm in the same growth stage (V 4 ), although the hollow cone nozzle increased the deposit levels on the plants. All the technologies tested in the study promoted a reduction of plant damage from fall armyworm attack. Corn productivity is directly related to the control efficiency of fall armyworm.

Improved quality of fungicide deposition and coverage of potato leaves using flat fan air-injector nozzle IDK

The aim of our experiment was to improve fungicide spray deposition and coverage of potato leaves by using air-injector nozzle types. We used two standard nozzle types a flat fan nozzle ST and a hollow cone nozzle TR, as well as a couple of air-injector nozzle types an air-injector compact nozzle IDK and a symmetric double flat fan air-injector nozzle TWIN (with a 30 ° forward and a 30 ° backward spray jet angle). Water-sensitive paper was placed on the upper, middle and lower part of the plant in order to determine the quality of fungicide deposition and the ability of droplets to penetrate lower parts of the plant. When using the air-injector compact nozzle IDK, potato leaves were covered well at all three levels of the plant. The use of the above-mentioned nozzle resulted in the lowest reduction in coverage value and droplet impression area from the top towards the lowest part of the plant. Furthermore, the nozzle created large enough droplets with sufficient mass and speed to penetrate the dense canopy all the way to the lowest part of the plant. When using the symmetric double flat fan air-injector nozzle TWIN, the angle of both spray jets was excessively wide in order for the droplets to reach the lower part of the plant despite a very large droplet impression area. The use of both standard nozzle types resulted in a poor spray mixture coverage of the middle and lower part of the plant. This predominantly occurred due to insufficient droplet size and the subsequent lack of kinetic energy. Results show that the use of a newer air-injector compact nozzle IDK improves the deposition and coverage of potato leaves with spray mixture.

Low-Loss-Spray-Application - The Scientific Basis

Summary Limited time frames caused by infection threat and weather demand for efficient pesticide application techniques in modern integrated and organic fruit farming. This demand is best complied by low volume spraying, since it minimizes traveling time and number of fillings per spray treatment, but also minimizes the probability of a contamination of the operator with concentrated pesticides. To obtain good spray deposition, low volume spray application demands small droplets which offer numerous benefits, but also carry a high drift potential. This feature threatened the technique, because no method for spray drift reduction has been available in order to make use of reduced buffer zones to water courses and non-target areas. A new method based on cross flow characteristics of the sprayer fan, canopy adapted forward speed and fan speed and a mixed set of hollow cone nozzles and air induction nozzles resulted in an approx. 85% reduction of particle drift deposits, so that the method has been registered in the official German list of drift reducing devices in the 75% drift reduction class. Besides drift reduction a canopy adapted fan speed also results in an enormous reduction of fuel consumption and noise emission as further environmental benefits of small droplets. An assessment of the influence of a canopy adapted forward speed and fan speed on spray deposit, relative spray cover age and droplet deposit density revealed a significant increase of the application efficiency, rising with decreasing canopy width and compensating a reduction of water volume and dose rate from canopy related dosing models. Testing a tower sprayer in orchards for use with reduced fan speed unexpectedly showed an unusable vertical air distribution. Alarmed by this finding, a subsequent testing of various fan types on a test bench disclosed a very unsatisfying vertical air distribution of many fan types and even within a production series the air distribution differed enormously. Especially an uneven horizontal reach of the air stream over working height is a major obstacle for a successful use of canopy adapted fan speed with all its benefits. Since a uniform vertical air distribution is the basic re quirement for a highly efficient and environmentally safer spray application not only in terms of the potential to reduce pesticide consumption, but also for reducing fuel consumption and noise emissions, testing and adjusting fans of orchard sprayers on a test bench is urgently needed. Because of the importance of the topic, three fruit growers associations in Austria, Italy and Germany together initiated the development of a new test bench to measure vertical air distribution of orchard sprayers.

Deposição de calda pulverizada na cultura da soja promovida pela aplicação aérea e terrestre

Este trabalho teve como objetivo avaliar o efeito da tecnologia de aplicação aérea e terrestre de fitossanitários na deposição de calda, na cultura da soja. Avaliou-se, após a aplicação de um traçador, a deposição nas partes inferior e superior do dossel da cultura, por meio de espectrofotometria. O ensaio foi conduzido no delineamento em blocos ao acaso, com quatro repetições e oito tratamentos (formas de aplicação): 1 - Terrestre (Ponta de jato cônico vazio-TXA 8002 e 180 L ha-1); 2 - Terrestre (Ponta de jato plano defletor duplo com indução de ar-AITTJ 11002 e 150 L ha-1); 3 - Terrestre (Ponta de jato plano defletor com indução de ar-TTI 11002 e 150 L ha-1); 4 - Terrestre (Ponta de jato plano defletor duplo-TTJ60 11002 e 150 L ha-1); 5 - Terrestre (Ponta de jato plano defletor-TT 11002 e 150 L ha-1); 6 - Aéreo (Atomizador rotativo e 40 L ha-1); 7 - Aéreo (Atomizador rotativo e 30 L ha-1); e 8 - Aéreo (Atomizador rotativo e 20 L ha¹). Também foi conduzido um estudo de espectro de gotas. As aplicações terrestres com ponta de jato cônico vazio e aérea (40 L ha-1) foram as mais eficientes em promover a penetração da calda no dossel, embora seus espectros de gotas sejam mais suscetíveis à deriva. A aplicação aérea mostrou-se viável tecnicamente, quanto à deposição de calda, em comparação aos tratamentos terrestres.

Effect of different pesticide application methods on spray deposits, residues and biological efficacy on strawberries

In agricultural food production, positive results can be obtained by using appropriate pesticides through the application of appropriate methods. In this study, we aimed to determine the effects of different spraying methods on spray deposits and drift, pesticide residues and biological efficacy on strawberries. For this purpose, strawberries were sprayed with dicofol by broadcast and band spraying. The effectiveness of different application methods was studied on 09 May, 2007 and 16 April, 2008. Broadcast sprayings were applied via hollow cone nozzles (HC) and air-assisted spinning cage nozzles (ASC). Band spraying was applied via flat fan nozzles (FF). Pesticide deposits on leaf surfaces, ground, drift and pesticide residues on strawberries were analyzed with Gas Chromatography/Electron capture detector (GC/ECD). Strawberries were analyzed based on dicofol residues up to 6 days after spraying. The results obtained showed that the highest pesticide deposits on leaf surfaces and also biological efficiency were obtained with FF in 2007 and 2008. The lowest pesticide deposits on ground were obtained by HC and the highest deposit of drift was obtained by ASC in 2007 and 2008. According to Commission Directive 2000/42/EC, the MRL’s of dicofol on strawberry is 0.02 mg/kg. In this study, residues on strawberries for all types of nozzles were below the suggested maximum residue level (MRL) of dicofol by Commission Directive 2000/42/EC in 2007 and 2008. Key words: Broadcast spraying, band spraying, hollow cone nozzle, flat fan nozzle, air-assisted spinning cage nozzle, biological efficacy, red spider mites, gas chromatography, electron capture detector (ECD).

Spray distribution uniformity of different types of nozzles and its spray deposition in potato plant

Spray distribution uniformity on sampling posts and spray deposition in potato plants were investigated with six different types of spray nozzles (standard flat fan, hollow cone, air induction and twin jet hydraulic nozzles, spinning disc nozzle and air assisted rotary atomizer). Spray pressures were 4 bar for the hydraulic nozzles and 1.5 bar for the spinning disc nozzle and air assisted rotary atomizer. All trials were conducted at 6.0 km h-1 travel speed. For the spray distribution uniformity, three different sampling materials (petri dish, water sensitive paper and aluminum strip) on the sampling posts were used. Spray mixture containing water and brilliant blue was used as spray liquid. The concentration of spray samples were corrected with the calibration of the degradation of the dye exposed to direct sunlight and in a dark ambience. The air induction and twin jet nozzles had the lowest means in coefficient of variation (CV%) at all sampling materials. The highest deposit at the middle of the plants was provided with the air induction and twin jet nozzles. The hollow cone nozzle had the lowest mean in deposition at the bottom of the plants. The amount of dye with the air assisted rotary atomizer transferring the top, middle and bottom of the plants respectively, 35.2, 38.9 and 37.2% was found to be deposited on the underside of the leaves. Key words: Hydraulic nozzle, spinning disc nozzle, rotary atomizer, spray deposition, spray uniformity, potato, pesticide application.

COMPARISON OF APPLICATION METHODS FOR TOBACCO BUDWORM CONTROL, 2010

Anthranilic diamide insecticides, two of which have recently been registered for use in tobacco, may be more persistent in plant tissue and move within leaf tissue to a great extent than other registered chemistries. These characteristics may allow anthranilic diamaide insecticides to be applied using different methods than standard materials used against TBW. Standard insecticide application methods for TBW control recommend a volume of 30 gpa water applied with 60 psi pressure using solid or hollow cone nozzles. Using one of the registered anthranilic diamaide insecticides registered in tobacco (Belt, Bayer CropScience) applied at a rate of 3.0 fl oz/acre, we compared 4 application volumes (5, 10, 20, and 50 gpa water) applied at 2 pressures (30 and 60 psi) to determine if applications at lower volumes and pressures were as effective as those at higher volumes with greater pressure. Greenhouse grown tobacco plants were transplanted on 4 May. Plants were treated with 0.8 fl oz/1000 plants Admire Pro 5 d prior to transplant to control early season tobacco flea beetle (Epitrix hirtipennis) and green peach aphid (Myzus persicae) populations. Four row plots, 50 ft in length, were established immediately after transplant. Plots were 0.018 acres each. Each treatment was replicated 4 times, and plots were arranged in an RCBD, blocked by replicate. Six wk after transplant, 10 plants each in rows 2 and 3 of each plot were infested with laboratory reared 2 instar TBW larvae, purchased as eggs from Chesapeake PERL (Savage, MD). Treatments were applied the d after larval infestation. Larval survival and leaf area consumed were rated 3, 7, and 14 d after foliar treatments were applied. Treatments were applied using a single nozzle boom fitted with a TG3 solid cone tip and powered by a CO2 pressurized backpack sprayer. Data were analyzed via Proc Mixed (SAS v. 9.1.3; Cary, NC) with replicate as a random variable. Each date was analyzed separately, not as a repeated measure.

EVALUATION OF SULFOXAFLOR (GF-2372) AGAINST TARNISHED PLANT BUGS IN COTTON, 2010

Insecticide efficacy trials were conducted during 2010 at the Northeast Research Station (NERS) near St. Joseph, LA (Tensas Parish) and the Macon Ridge Research Station (MRRS) near Winnsboro, LA (Franklin Parish). Cotton seed (DP 555 BG/RR) was planted into a Commerce silt loam on 25 May at NERS (trial 1) and a Gigger silt loam on 1 Jun at MRRS (trials 2 and 3). Plot size was four to eight rows (40-inches on row centers) X 50 ft with four replications. Insecticides were applied with a highclearance sprayer and compressed air system calibrated to deliver 12 GPA through TeeJet TX-10 hollow cone nozzles (2/row) at 48 psi at NERS and at 9.5 GPA through TeeJet TX-8 hollow cone nozzles (2/row) at 50 psi at MRRS. In trial 1, insecticides were applied on 20 and 29 Jul, and post-treatment evaluations were made on 3, 7 DAT1, and 2, 7, 12 DAT2. In trial 2, insecticides were applied on 3 Aug and post-treatment evaluations were made on 3, 8, 10, 14 DAT. In trial 3, insecticides were applied on 25 Aug and post-treatment evaluations were made on 3, 7, 10 DAT. Plots were sampled with a standard 2.5 x 2.5 ft black cloth shake sheet by taking two samples on two-four rows (10 row ft total) of each plot. Data were subjected to ANOVA and means separated according to DNMRT. Rainfall of 7.61, 1.46, and 0.4 inches occurred during trials 1, 2, and 3, respectively.

EFFICACY OF SELECTED INSECTICIDES AGAINST COTTON APHID ON COTTON, 2010

Cotton was planted on a silt loam soil in Grenada, MS on 27 April 2007. Plot size was 4 rows by 40 ft long planted on 38 inch centers. Statistical design was a RCB with 4 replications. Insecticides were applied with a tractor mounted sprayer calibrated to deliver 10.0 gpa at 65 psi through TX-6 Hollow Cone nozzles (2 per row). All treatments were applied on 6 Jul. All treated areas received 0.5 inches of rainfall within 10 min of application. Estimates of aphid density were determined by counting aphids on the bottom side of leaves on 5 randomly selected leaves per plot 3 nodes down from the terminal 3 DAT. Data were analyzed with ANOVA and means were separated using a Fisher’s Protected LSD (P ≤ 0.05).

EFFICACY OF FOLIAR INSECTICIDES AGAINST BEAN LEAF BEETLE IN SOYBEAN (TEST 2), 2010

On 6 Aug, a soybean efficacy trial was conducted on a commercial farm in Shelby, MS in the Mississippi Delta. Plot size was 12.6 feet wide by 75 ft long planted on 38 inch row centers. Statistical design was a RCB with 4 replications. Insecticides were applied with a tractor-mounted sprayer calibrated to deliver 10.0 gpa at 60 psi through TX-6 Hollow Cone nozzles (19 in nozzle spacing). Treatments were applied on 6 Aug. Estimates of bean leaf beetle density were determined by taking 25 sweeps per plot with a standard 15 inch sweep net 2 and 6 DAT. Data were analyzed with ANOVA and means were separated using a Fisher’s Protected LSD (P ≤ 0.05).

EVALUATION OF INSECTICIDE EFFICACY AGAINST SOYBEAN LOOPER IN SOYBEANS, 2010

A field trial evaluated selected foliar treatments against soybean looper (SBL) on R5.5 stage soybeans at the Macon Ridge Research Station (Franklin Parish). Soybean seed were planted into a Gigger-Gilbert silt loam soil on 15 Apr. Plot size was four rows (40inches on centers) X 45 ft. Treatments were arranged in a RCB design with four replications. Insecticides were applied with a highclearance sprayer and compressed air system calibrated to deliver 6 gpa through TeeJet TX-8 hollow cone nozzles (2/row) at 50 psi. Insecticides were applied on 13 Aug, and post-treatment evaluations were performed at 3, 7 and 11 DAT. Insecticide efficacy was measured by taking 25 sweep-samples with a sweep net (15 inches diameter) in each plot and recording the number of SBL larvae > 1⁄2 inch. Data were subjected to ANOVA and means separated according to DNMRT. Total rainfall of 0.76 inches occurred during the trial period.

EFFICACY OF FOLIAR INSECTICIDES AGAINST BEAN LEAF BEETLE IN SOYBEAN, 2010A

This trial was conducted on a commercial farm in Tchula, MS. The soybean field was planted on 15 inch rows. One week prior to this trial, the farmer had applied Baythroid XL at 0.03 lb (AI) with unsatisfactory results. Plot size was 10 rows by 75 ft long. Statistical design was a RCB with 4 replications. Insecticides were applied with a tractor-mounted sprayer calibrated to deliver 10.0 gpa at 60 psi through TX-6 Hollow Cone nozzles (2 per row). Treatments were applied on 13 Aug. Estimates of bean leaf beetle density were determined by taking 25 sweeps per plot with a standard 15 inch sweep net 4 DAT. Data were analyzed with ANOVA and means were separated using a Fisher’s Protected LSD (P ≤ 0.05).