Towards generalization of visual anemometry using honami wave theory

Honami is a phenomenon in which wavelike motions propagate downstream along the top of homogeneous canopy fields such as cereal crops, alfalfa fields, rice fields, and grasses. These waves occur when a high momentum coherent fluid parcel, also known as a sweep, is accelerated in the streamwise direction and moves towards the canopy, bending over a group of plant stalks. The phase velocity of honami waves can be interpreted as the frozen histories of gust velocity or the convection velocity of the large eddies with which the gusts are associated. The literature to date has focused on identifying the relationship between the wave properties and mean boundary layer statistics above the canopy and concluded that honami speeds are significantly higher than the mean wind speed at the canopy height. Our research examines the ability of honami speeds to identify instantaneous flow properties and turbulent properties. We will present the relationship between gust speeds and honami phase speeds and compare the results of quadrant analysis for both the canopy and the flow. The combination of these relationships can contribute to the advancement of generalization of visual anemometry, which is the process of inferring wind conditions from visual observations of vegetation kinematics without prior knowledge of the flow or observed canopy.