Submitted to: ASAE Annual International Meeting
Publication Type: Proceedings
Publication Acceptance Date: 6/1/2003
Publication Date: 7/27/2003
Citation: Fife, J.P., Derksen, R.C., Ozkan, H.E. 2003. Effect of Hydraulic Nozzles on the Viability of a Biological Pest Control Agent. ASAE Annual International Meeting. Paper No. 031063.
Technical Abstract: Biological pest control options for pest control are being evaluated to manage pest problems where there are limited or no effective chemical control options. The effect of flow through conventional pesticide delivery systems on biological pest control agents is not well established. Hydrodynamic stresses during flow through a hydraulic nozzle can damage a biological pest control agent. The objective of this research was to evaluate damage to entomopathogenic nematodes (EPNs) delivered through conventional nozzles. Computational fluid dynamics was used to simulate the internal flow through relatively small versions of a flat fan and a hollow cone nozzle, two, relatively common, conventional nozzle types, and to compute energy dissipation rates. Average energy dissipation rates near the exit orifice were significantly higher for the flat fan than for the hollow cone nozzle. A bench-top, experimental flow device was used to evaluate the relative damage of four different EPNs species through relatively small flat fan, hollow cone, and full cone nozzles. For a range of flow rates, no significant reduction in EPN damage was observed for the full cone nozzle but greater reductions in nematode viability were observed for the flat fan nozzle than the hollow cone nozzle design. Greater EPN damage observed through the flat fan nozzle is consistent with the higher energy dissipation rates within the nozzle. Greater damage was also observed for the larger EPN species tested, S. glaseri. The flow field characteristics and energy dissipation rates computed suggest that the cone type nozzles are more suitable for delivery of EPN than a flat fan nozzle to avoid damage that will reduce EPN viability.