You are being redirected because this document is part of your ASTM Compass® subscription.
    This document is part of your ASTM Compass® subscription.


    Spray Characterization by Optical Image Analysis

    Published: 2016

      Format Pages Price  
    PDF (4.0M) 21 $25   ADD TO CART
    Complete Source PDF (23M) 224 $77   ADD TO CART

    Cite this document

    X Add email address send
      .RIS For RefWorks, EndNote, ProCite, Reference Manager, Zoteo, and many others.   .DOCX For Microsoft Word


    Liquid spray application is the preferred mode of product delivery in a gamut of industries, including coatings and paint; personal care; household, industrial, and institutional; food and beverage; transportation; agriculture; and many others. Accurate measurement of spray characteristics, including droplet size distribution, coverage, atomization, droplet velocity, droplet interaction with solid surfaces, and spray drift, is critical to ensure spray systems meet the delivery and efficacy demands of the application. Sophisticated transmittance-based nonintrusive methods such as laser diffraction (particle measurement systems, e.g., Malvern, Sympatec), laser interferometry (phase Doppler anemometry or particle dynamics analysis), pulsed laser high-speed image analysis (particle/droplet image analysis, e.g., Oxford VisiSizer, LaVision ParticleMaster), and high-speed videography are most commonly used for spray characterization. Though highly efficient and extremely accurate, the instrumentation can be expensive, complicated to operate, sensitive to drop shape, limited by optical density of spray media, and sensitive to external elements such as vibration and temperature, coupled with a very narrow field of view that can restrict wide-scale adoption and field deployment of these methods. The objective of this research was to demonstrate that the development of a series of reflectance-based, wide-angle, direct, full-fan optical imaging-image processing methods for spray characterization is possible. Recent advancements in digital image quality and computational ability allow the use of readily accessible off-the-shelf digital cameras with assistive lighting accessories to characterize droplet size distributions. Focusing on agricultural spray applications, methods were developed to extract spray droplet size distribution, sheet length, spray sheet breakup mechanism, and spray velocity data from spray images. Sample agricultural tank mixtures containing actives and commercial and proprietary drift control adjuvants were evaluated. Data were obtained from this imaging method and compared to data collected using laser diffraction in a wind tunnel. The potential for extending the imaging method to a field-deployable real-time spray performance screening and evaluation technique was scoped.


    spray, drift, optical imaging, droplet size, velocity, sheet breakup

    Author Information:

    Sarkar, Sounak
    Ashland Specialty Ingredients, Care Specialty, Bridgewater, NJ

    Kamin, Surya
    Ashland Specialty Ingredients, Care Specialty, Bridgewater, NJ

    Kruger, Greg R.
    University of Nebraska–Lincoln, Dept. of Agronomy and Horticulture, West Central Research and Extension Center, North Platte, NE

    Committee/Subcommittee: E35.22

    DOI: 10.1520/STP159520160036