Droplet spectra and high-speed wind tunnel evaluation of air induction nozzles

Abstract

A series of air induction nozzles were tested in a high-speed wind tunnel. Droplet size spectra were measured for four air induction nozzles (IDK-120-01, IDK-120-02, IDK-120-03 and IDK-120-04) each at three spray pressures (0.3, 0.4 and 0.5 MPa) and seven different air velocities (121.7, 153.4, 185.5, 218.4, 253.5, 277.5 and 305.5 km·h⁻¹). The measurement distance (0.15, 0.25 and 0.35 m) from the nozzle orifice was found to be important for the atomization of the droplets. The response surface method was used to analyze the experimental data. The results indicated that Dv_0.1 and Dv_0.5 of the droplets decreased quasi-linearly with increased wind speed, while Dv_0.9 was affected by the quadratic of wind speed. Dv_0.1, Dv_0.5 and Dv_0.9 of the droplets were all proportional to the orifice size, and were not markedly influenced by the spray pressure. The percentage of the spray volume consisting of droplets with a diameter below 100 mm (%<100 mm) was found to be quadratically related to wind speed, and was not markedly influenced by the spray pressure and orifice size. However, the effect of the orifice size on the %< 200 mm could not be ignored.

Keywords

air induction nozzle / wind tunnel / aerial spray / droplet size spectra

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (31601228, 31701315), the Youth Science Fund of the Beijing Natural Science Foundation (6164032), the Youth Science Fund of Beijing Academy of Agriculture and Forestry Sciences (QNJJ201631), and Beijing Talent Program for Ruirui Zhang.

Compliance with ethics guidelines

Qing Tang, Liping Chen, Ruirui Zhang, Min Xu, Gang Xu, Tongchuan Yi, and Bin Zhang declare that they have no conflicts of interest or financial conflicts to disclose.

This article does not contain any studies with human or animal subjects performed by any of the authors.

RIGHTS & PERMISSIONS

The Author(s) 2017. Published by Higher Education Press. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0)