Leidenfrost Effect Physics Project Ideas & Rotating Motion Explanation

[coolie]

Can someone give me some ideas on my current physics Project
I am currently measureing the effect of temperature of a hot plate on the life time of a water droplet!
But I am looking of some realistic ideas on other variables that i can change on top of the leidenfrost effect.
Also I am abserving this rotating motion of the suspending liquid, where it spins with a star characteristic. Does anyone know why this happen?
Thank you,:rofl:
You can write to me vis email : dragoon.li@gmail.com

 

[Astronuc]

Also I am abserving this rotating motion of the suspending liquid, where it spins with a star characteristic.

What does "star characteristic" mean?

It could simply mean that surface tension or liquid cohesiveness in the drop is not azimuthally uniform, which is quite natural and expected.

 

[Astronuc]

Usefuel reference - http://en.wikipedia.org/wiki/Leidenfrost_Effect

and

http://www.wiley.com/college/phy/halliday320005/pdf/leidenfrost_essay.pdf

The Leidenfrost point (LFP) is the minimum surface temperature required to support film boiling, and film boiling is undesirable in a heat exchanger because the vapor phase has a significantly lower heat transfer coefficient (lower thermal conductivity), which will result in higher temperatures on the heated surface which is being cooled by boiling liquid. Higher temperatures can lead to premature or catastropic structural failure, and in aqueous systems, lead to corrosion which degrades heat transfer properties, and can degrade structural integrity.

 

[karmacelina]

this phenomenon that you've observed has been observed and studied by others -- the star pattern is called a "leidenfrost star"... which was "discovered" in the 50s by holter and glasscock.

here's the reference:

N. Holter and W. Glasscock, “Vibrations of evaporating liquid drops,”
J. Ac. Soc.
Am., vol. 24, no. 6, pp. 682–686, 1952.

hope this helps.

 

[paranormal]

The Leidenfrost effect is a fascinating phenomenon that occurs when a liquid comes into contact with a surface that is significantly hotter than its boiling point. The liquid forms a vapor layer between itself and the surface, which reduces the contact area and slows down the rate of evaporation. This results in the liquid being able to "levitate" and move around on the surface.

One idea for your project could be to investigate the effect of different surface materials on the Leidenfrost effect. You could test surfaces with different levels of roughness, conductivity, or thermal mass to see how they affect the lifetime of the water droplet.

Another interesting variable to explore could be the shape of the surface. Does a concave or convex surface have a different effect on the Leidenfrost effect? How does the shape of the droplet itself (e.g. spherical, oblong) affect its movement on the surface?

As for the rotating motion of the suspended liquid, this is likely due to the vapor layer created by the Leidenfrost effect. As the droplet moves around on the surface, the vapor layer can become uneven, causing the droplet to spin. You could investigate how different variables, such as the temperature of the surface or the size of the droplet, affect the spinning motion.

Overall, there are many interesting avenues to explore within the Leidenfrost effect and its related rotating motion. I would suggest conducting thorough research and designing controlled experiments to gather data and draw conclusions. Good luck with your project!