Observation of gas flow around plants using Schlieren imaging system and high-refractive-index gas

Abstract

The fruits of many plant are carried and flowers are also swayed by the wind. If the flow of air around plants can be visualized, the science behind it will be interestingly illustrated. In this study, the gas flow around cherry blossom fruits, clover flowers, maple seed propellers, and dandelion pappi as spherical and propeller-shaped samples is demonstrated using a Schlieren optical system and a high-refractive-index gas. The observed gas flow corresponding to the sample shape was well characterized by fluid dynamics features such as the Coandă effect. The results of experiments in which the flow of gas around plants is visualized are useful as a scientific education material for fluidics and optics.