Tipputiheys

Tipputiheys, literally “drop density” in Finnish, is a parameter used in spray technology to describe the concentration of droplets per unit area produced by a spraying or dripping event. It is employed to evaluate spray quality, coverage uniformity, and drift potential, particularly in agriculture, horticulture, and irrigation systems.

Etymology and usage: The term originates from Finnish technical literature and is used mainly in Nordic contexts. In English-language texts the concept is often referred to as droplet density, though “tipputiheys” appears in Finnish manuals and standards that address spray deposition and application efficiency.

Measurement and methodology: Tipputiheys is typically expressed as droplets per square millimeter (or per square centimeter) on a reference plane. It is measured using optical imaging with droplet-counting software or laser-based droplet analyzers, often in combination with data on droplet size distribution. Measurements may be performed at representative distances from the nozzle or at the target surface under controlled conditions.

Factors and implications: The density is influenced by nozzle design, spray pressure, liquid properties (viscosity, surface tension), spray angle, distance to target, and application speed. Higher density generally improves potential coverage but can raise drift risk and require more uniform deposition. It is not a standalone measure of effective deposition, since wetting, evaporation, and roughness of the surface also affect final deposits.

Applications and limitations: Tipputiheys informs nozzle selection, pressure settings, and drift control strategies in agricultural spraying and greenhouse irrigation. It complements, but does not replace, measurements of coverage, deposition, and droplet-size distribution.