Oscillating Droplet

Application ID: 1378

Cemented tungsten carbides are hard metals used in steel cutting tools. They are produced by heating a powder consisting typically of tungsten carbide (WC) grains and cobalt (Co) grains. When the powder is heated, the cobalt melts but the tungsten carbide remains solid. The liquid cobalt glues the tungsten carbide grains together and forces air to flow out of the material. When the medium is cooled down, a solid hard metal forms. The process is called liquid phase sintering.

You can determine the character of the flow of air and liquid cobalt by simulating a droplet of cobalt surrounded by air. Such a simulation reveals the relevant time scales and shows whether the flow is dominated by inertial or viscous forces.

This example shows how COMSOL Multiphysics can simulate a liquid cobalt droplet using a reinitialized mass-conserving level set method. The model studies an initially ellipsoidal droplet that starts to oscillate because of the large surface tension of liquid cobalt. From the results you can study the frequency and damping of the droplet’s oscillations.