Looking at the microworld with the naked eye Can the slow motion of something very tiny be similar...
-
Upload
grant-dalton -
Category
Documents
-
view
217 -
download
0
Transcript of Looking at the microworld with the naked eye Can the slow motion of something very tiny be similar...
Looking at the microworld with the naked eye
Can the slow motion of something very tiny be similar to a quicker motion of something considerably larger?
Maciej LisickiMaria Ekiel - Jeżewska
What does it mean 'similar'? Identical shape is not enough...
http://www.tukan-webdesign.de/krusenstern2/Krusens%20neu%20als%20Taste%20m.Schatt400x383.jpghttp://www.mmszczecin.pl/8307/2007/9/20/klub-czytelnika-zaprasza?category=interwencje
L
ρ, μU
Reynolds number
LU
Re
L
U
,Density and viscosity of the liquid
Flow velocity
Characteristic size
LU
Re
L
U
,
Flow similarity principle
Two flows having the same Reynolds numbers have the same character.
Low viscosity, little size,low velocities
= High viscosity, big size,high velocity
LU
Re
Low viscosity + little objects
Welcome to the microworld!
Rhodobacter E. coli
Howard Berg’s Laboratory
BACTERIA IN WATER
High viscosity + large objects
MACROWORLDMICROWORLD
Re
Flows with similar Reynolds numbers are similar!
Instead of looking at swimming microobjects, we can observe large bodies but in a Very Viscous Liquid!