Interesting Phenomena on my Windshield

[Aero51]

So I was driving my dads truck to pick up my sister when I noticed a very interesting pattern in the raindrops sliding across the truck windshield. It was not raining, but I am currently in the northeast and we just got done with a snowstorm so they really weren't raindrops but simply melted snow... Anyway, I observed that the "raindrops" tended to follow a zigzag pattern as they climbed the windshield. This wasn't one path in particular, many of them seemed to move like recognized swimmers akin to a "glider" in the Game of Life. Here is a picture from Wikipedia:

It was very fascinating, so much so that I almost missed my exit! I am not sure if the fact that I was following a tractor trailer makes a difference. Perhaps the vortex shedding frequency behind the trailer had something to do with the water pattern on the windshield.

Does anyone have any idea what would be causing this pattern?

 

[Achy47]

Thank you for sharing your observation with us. I find your description of the "raindrop" pattern on your truck windshield very interesting. It is possible that the vortex shedding frequency behind the tractor trailer could have an impact on the movement of the water droplets on your windshield. However, there are also other factors that could be contributing to this pattern.

One possible explanation is the aerodynamics of the truck and its interaction with the surrounding air. As the truck moves through the air, it creates a wake behind it, which can affect the movement of the water droplets on the windshield. The shape and speed of the truck can also play a role in this phenomenon.

Another factor to consider is the surface tension and adhesion of the water droplets. The shape of the truck's windshield and the direction of the wind can influence how the droplets move and interact with each other. The temperature and humidity levels can also impact the behavior of the water droplets.

In order to fully understand the cause of this pattern, further research and experimentation would be needed. It would be interesting to see if the same pattern occurs on other vehicles in similar weather conditions. I would also suggest recording the speed and direction of the wind, as well as the temperature and humidity levels, to see if there is a correlation with the observed pattern.

Thank you for bringing this observation to our attention. It is through curiosity and observation like yours that we can continue to learn and discover more about the world around us. Keep observing and questioning, and who knows what other fascinating patterns you may uncover in the future.