tilkumise

Tilkumine is an Estonian term meaning the dripping of liquid droplets, and it is used to describe the process by which droplets form and detach from a liquid surface, edge, or nozzle. The word combines tilk (drop) with the suffix -umine, denoting a process or state.

In a typical dripping scenario, liquid accumulates at a tip or over a surface until a thinning neck forms due to surface tension and gravity. When the neck becomes thin enough, it pinches off, releasing a drop. The remaining column or surface then repeats the cycle. Dripping can occur at low flow rates and is often contrasted with jetting, which occurs at higher flow rates where a continuous jet forms before breaking into droplets.

Tilkumine occurs in many everyday and industrial contexts. Everyday examples include a leaking faucet or a gutter outlet after rainfall. Industrially, controlled dripping is used in applications such as drip irrigation, inkjet printing, and certain chemical processes. In manufacturing and quality control, reducing unintended tilkumine is important for precision and waste reduction, while intentional dripping can be used to meter volumes or create droplets of specific sizes.

Several factors influence tilkumine, including liquid properties (surface tension, viscosity, density), surface characteristics (wettability, roughness), geometry (nozzle or edge size), and operating conditions (flow rate, pressure, temperature). In scientific and engineering analyses, tilkumine is often described using fluid dynamics concepts and dimensionless numbers that compare forces of inertia, viscosity, and surface tension.

See also: dripping faucet, capillary action, atomization, drip irrigation.