STP1112: Effects of Pump Type on Atomization of Spray Formulations

    Chapple, AC
    Graduate Research AssociatePost-Doctoral Research AssociateHead and Professor, Laboratory for Pest Control Application Technology, The Ohio State University, OARDC, Wooster, OHIO

    Downer, RA
    Graduate Research AssociatePost-Doctoral Research AssociateHead and Professor, Laboratory for Pest Control Application Technology, The Ohio State University, OARDC, Wooster, OHIO

    Hall, FR
    Graduate Research AssociatePost-Doctoral Research AssociateHead and Professor, Laboratory for Pest Control Application Technology, The Ohio State University, OARDC, Wooster, OHIO

    Pages: 13    Published: Jan 1992


    Abstract

    The effects on the atomization process with respect to droplet spectra were investigated for three pump systems (a rotary vane pump, a piston pump, and a diaphragm pump) and compared with an air pressure system. The test substances evaluated were water, Ortho X-77 (0.0625% and 0.5%), Windfall and Nalcotrol polymers, and two placebo (blank) insecticides (an emulsifiable concentrate and a wettable powder). All formulations were tested at field rates. All work was done using a TeeJet XR8004VS flat fan nozzle, and a Hardi 1553-12 hollow cone nozzle with a grey swirl. The effect of recirculation of the formulations on the eventual droplet spectra was also investigated. All other spraying parameters were kept constant. Droplet spectra were assessed along the long axis of the spray pattern using an Aerometrics PDPA-100 system, and a Velmex “Unislide” xyz-positioner.

    Results indicate that droplet spectra of formulations containing polymers shift significantly with time of recirculation: Dv0.5 decreased by as much as 300 μm for Nalcotrol. The time taken for the Dv0.5 to stabilize depended upon pump type. Water, Ortho X-77, and the two blank formulations remained unaffected by pump type or recirculation. The effect of different mixing regimes prior to atomization was also investigated for Windfall and Nalcotrol.

    Keywords:

    Droplet atomization, lasers, pumps, adjuvants, drift, nozzles, drop spectra


    Paper ID: STP16882S

    Committee/Subcommittee: E35.22

    DOI: 10.1520/STP16882S


    CrossRef ASTM International is a member of CrossRef.