Kansas State University Biological and Agricultural Engineering Department Spray Droplet Analysis of Air Induction/Venturi Nozzles Using WRK’s DropletScan  Technology Robert E. Wolf Extension Specialist Agrichemical Technology Biological and Agricultural Engineering Dept.

Kansas State University Biological and Agricultural Engineering Department New Technology for the Spray Industry

Kansas State University Biological and Agricultural Engineering Department Nozzle is still an important part of the application process! l Determines the application rate l Determines the uniformity l Determines the coverage l Determines the drift potential

Kansas State University Biological and Agricultural Engineering Department What’s really new? ‘Air Assist’ Sprayers and Nozzles

Kansas State University Biological and Agricultural Engineering Department Air-Induction/Venturi Nozzles Where air is drawn into the nozzle cavity and exits with the fluid.

Kansas State University Biological and Agricultural Engineering Department Example Design -TurboDrop l Air inlet/venturi l Mixing Chamber - air and spray solution blended l Pattern contains large air-bubble drops l Better Penetration? l Reduced run-off? l Improved coverage?

Kansas State University Biological and Agricultural Engineering Department 1/2 of spray volume = larger droplets VMD 1/2 of spray volume = smaller droplets

Kansas State University Biological and Agricultural Engineering Department What to Expect in the Future? Utilizing technology to enhance the application precision of chemicals l Match the crop protection product to the target l Adhere to label guidelines based on an industry standard –ASAE X-572 l Minimize drift

Kansas State University Biological and Agricultural Engineering Department Objectives of this study: l Compare droplet size information of conventional vs. air- induction/venturi style nozzles l Determine if the DropletScan  software will provide quick and useful information about various nozzle types.

Kansas State University Biological and Agricultural Engineering Department DropletScan  is Field Ready & Simple! System Components

Kansas State University Biological and Agricultural Engineering Department Basic system processes: l Aquiring an image from water senstive paper or other color contrasting material. l 2-step process –Low resolution –High resolution l Select report options

Kansas State University Biological and Agricultural Engineering Department l Droplet counts and size l Histogram - number of droplets in each size category l Histogram - Amount of total volume in each size category l % area coverage on target l Estimate of GPA on target l VMD VMD (0.1) VMD (0.9) Sample Printout

Kansas State University Biological and Agricultural Engineering Department l Droplet counts and size l Histogram - number of droplets in each size category l Histogram - Amount of total volume in each size category l % area coverage on target l Estimate of GPA on target l VMD VMD (0.1) VMD (0.9) Sample Printout

Kansas State University Biological and Agricultural Engineering Department Procedures Involved: l Use the spot cards during spray run – (flat or in canopy) l Scan cards and analyze by software l Droplet stains are measured l Spread factors are used for material l Equivalent droplet diameter is calculated –% target area being covered –application rate

Kansas State University Biological and Agricultural Engineering Department Drop Data Descriptions: l D v0.1 (µm) - 10% of the spray volume in drops < number reported l D v0.5 (µm) - 50% of the spray volume in drops < number reported (also is VMD- volume median diameter) l D v0.9 (µm) - 90% of the spray volume in drops < number reported

Kansas State University Biological and Agricultural Engineering Department Materials and Methods: l 3 conventional nozzles l 4 air-induction/venturi l 138, 276, 551 kPa l 76 L/A, 76cm, 51cm

Kansas State University Biological and Agricultural Engineering Department Collection Procedure: l Software written to read cards left and right from center of sprayer. l Adaptable for any length boom. l Number of cards and step distance important for swath width calculations and pattern uniformity

Kansas State University Biological and Agricultural Engineering Department Sample of a collection: l Passed sprayer over a collector board with five equally spaced water-sensitve cards attached. l 5 cards were collected for each of the 7 nozzles at each pressure.

Kansas State University Biological and Agricultural Engineering Department TT XR TF TD AI LU DV

Kansas State University Biological and Agricultural Engineering Department XR kPa Turbodrop kPa

Kansas State University Biological and Agricultural Engineering Department Results and Discussion

Kansas State University Biological and Agricultural Engineering Department Summary Table of Droplet Statistics

Kansas State University Biological and Agricultural Engineering Department VMD for All Nozzles:

Kansas State University Biological and Agricultural Engineering Department VMD for Air-Induction/Venturi Nozzles

Kansas State University Biological and Agricultural Engineering Department VD 0.1 and 0.9 All Nozzles D v0.1 (µm) - 10% of the spray volume in drops < number reported D v0.9 (µm) - 90% of the spray volume in drops < number reported

Kansas State University Biological and Agricultural Engineering Department VD 0.1 and 0.9 Air-Induction/Venturi Nozzles

Kansas State University Biological and Agricultural Engineering Department Summary of Findings: l Air-Induction/Venturi nozzles have larger droplet spectums than the conventional nozzles. l Air-Induction/Venturi nozzles have a smaller portion of the spectrum that is highly drift prone than the conventional nozzles.

Kansas State University Biological and Agricultural Engineering Department Summary continued: l Air-induction/venturi nozzles were not significantly different in reported droplet statistics, especially at higher pressures. l Pattern quality may not be sufficient for uniform and adequate coverage at the lower end of the pressure range. l At the higher pressures adequate coverage does appear to exist.

Kansas State University Biological and Agricultural Engineering Department Summary continued: l Judgement on field performance should be reserved until adequate efficacy and drift data are evaluated along with droplet data. l The WRK software system does appear adequate to analyze field collected data. l Higher application rates may not work as well as lower rates and off-target (drift) for the scanning software.

Kansas State University Biological and Agricultural Engineering Department WRK Droplet Scan Setup l Dynamic testing of droplet size l Utilize Spraying Systems/Ciba water/oil sensitive papers without any dye l Other collectors may be used if enough color contrast can be achieved Determine what is happening as it occurs!

Kansas State University Biological and Agricultural Engineering Department Important to note that: l Represent droplets that are hitting the target rather than those that are leaving the nozzle. l Will measure stains as small as 50 microns. l Good analysis of lower application rates and driftable size fines. l Humid/moist conditions currently will not allow system to be effective.

Kansas State University Biological and Agricultural Engineering Department Droplet Scan uses at KSU l High speed aircraft evaluations l Ground sprayer evaluations –field crop and Turf l New nozzle evaluations –CP, TF, TT, A-I, TTF l Drift evaluations –setup and tank mix additives l Establish a database for typical droplet statistics from all nozzles

Kansas State University Biological and Agricultural Engineering Department Future Reports:

Kansas State University Biological and Agricultural Engineering Department Thanks

Kansas State University Biological and Agricultural Engineering Department Number and Volume of Droplets at 20 psi

Kansas State University Biological and Agricultural Engineering Department Number and Volume of Droplets at 40 psi

Kansas State University Biological and Agricultural Engineering Department Number and Volume of Droplets at 80 psi

Kansas State University Biological and Agricultural Engineering Department % Volume of Droplets

Kansas State University Biological and Agricultural Engineering Department

Current Prices

Kansas State University Biological and Agricultural Engineering Department

Plot Layout l 3 reps l 7 nozzles l 3 psi’s l 20 GPA l Gromoxone l 10’ boom l 5’ buffer

Kansas State University Biological and Agricultural Engineering Department Air -Induction/Venturi Nozzle Field Results

Kansas State University Biological and Agricultural Engineering Department