Nozzles variable cone

Figure 8.8 Two mycopesticide use scenarios showing droplet size spectra expressed as diameters (in p,m) with adjacent volume scale (in pi) and estimated particle distributions in droplet size classes, (a) The atomisers for migrant pest control (usually mounted on vehicles) are both shown applying a blank ULV oil formulation (from) Griffiths and Bateman, 1997) (b) hydraulic atomisers, including different settings of a variable cone nozzle, atomising water +0.1% Agral at 300 kPa (see text)...

The ability of a hydrocyclone to separate a certain diameter solid particle (fineness of separation) is affected by the differential pressure between the inlet and overflow, the density difference between the solid particles and the liquid, and the geometry and size of the cone and inlet nozzle. The pressure drop through the cone is the critical variable in terms of affecting fineness of separation and is itself a function of flow rate. Thus, the lower the flow rate, the lower the pressure drop and the coarser the separation. A minimum flow must be maintained through each cone to create the required pressure drop and rotary motion to ensure separation. 

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