Spray penetration

To estimate amount of spray penetrating the canopy and depositing on the ground, we collected spray on Kromekote paper cards. Tables I-IV provide deposit data from several aerial application projects. As expected more spray was recovered on the ground in the open forest than was recovered beneath trees. 

In the analysis considered in the preceding section, it was assumed that a uniform spray had been established initially and that once ignited, each droplet burned with an envelope flame around it. These conditions have been achieved reasonably well in the laboratory for various fuel-lean sprays [65]. However, in practical systems the sprays are not uniform, the manner in which the spray penetrates the oxidizing gas is important, and a cloudburning mode of combustion (in which diffusion flames surround groups of droplets, see the last paragraph of Section 3.3.6) may occur [2], [79]. These realities motivate studies of spray penetration and cloud combustion. 

The presentation of the subject of spray combustion in Chapter 11 is not greatly different from that in the first edition. An updated outlook on the subject has been provided, and the formulation has been generalized to admit time dependences in the conservation equations. The analysis of spray deflagration has been abbreviated, and qualitative aspects of the results therefrom have been anticipated on the basis of simplified physical reasoning. In addition, brief discussions of the topics of spray penetration and of cloud combustion have been added. 

Pesticide Spray Penetration and Thermal Comfort of Protective Apparel for Pesticide Applicators... 

One can also find a functional form for the trajectory of the large droplets that are formed at the CBL. The path of these droplets represents the maximum spray penetration. Since they are not connected to the jet and are in direct contact with a strong gas flow, they do not necessarily follow a path of the form of (29.9) anymore. A schematic view of the trajectory of these drops is shown in Fig. 29. Ic with a local coordinate system attached to the CBL for convenience. In general most applications of LJICF are concerned with high momentum ratios for which the jet deflection is not pronounced. For those cases, it is fair to assume that the droplets formed at the CBL have a zero initial velocity in the x-direction as they separate fi om the jet and have an initial upward velocity of mj. As these droplets leave the jet, they lose their vertical velocity and speed up in the gas-streamwise direction and finally reach their terminal x-direction velocity. Of course, all these are true for one droplet without considering its interaction with other droplets and also with neglecting the effects of evaporation. With these assumptions, the equations governing the motion of the drop take the form... 

Wu et al. [5] extended Wu et al. [1] by studying various characteristics of the spray plume and proposed the following relation for the maximum spray penetration ... 

Although various correlations offered for the spray penetration have used different functional dependence on xjd, most agree on a power of around 0.3-0.5 for q. This smaller power (compared to that of q in (29.7) for jet trajectory) is reasonable because the droplets forming the upper boundary of the spray plume are mainly... 

A phenomenological model for the jet penetration, based on experiments using the shadowgraph technique Extended Wu et al. [1] for spray penetration and width Experimental study focused on surface waves and spray characteristics... 

Authors Description of the study Correlations for jet spray penetration... 

System Variable Input Effect on liquid sprays penetration distance (L)... 

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