what is the relation between size and strength of a large-scale eddy?

Roule · October 4, 2015, 22:53

hi,

how is the strength of a large scale eddy related to its size.

for example, suppose there are 2 large scale eddies -
(1) one with dia. 10 cm and,
(2) another with dia. 8 cm.

which will have higher strength? it seems that the 10cm dia. is the answer, but is there any mathematical relation between size and strength of this eddy.

also, which parameter is used for measuring eddy strength - vorticity or energy.

it will be great if someone can suggest any relevant journal paper on this topic.

i am asking this regarding turbulence in open channel flow.

FMDenaro · October 5, 2015, 03:36

Quote:

Originally Posted by Roule

hi,

how is the strength of a large scale eddy related to its size.

for example, suppose there are 2 large scale eddies -
(1) one with dia. 10 cm and,
(2) another with dia. 8 cm.

which will have higher strength? it seems that the 10cm dia. is the answer, but is there any mathematical relation between size and strength of this eddy.

also, which parameter is used for measuring eddy strength - vorticity or energy.

it will be great if someone can suggest any relevant journal paper on this topic.

i am asking this regarding turbulence in open channel flow.

generally, the spectral energy is the correct indicator... in a standard energy cascade, the smaller is the structure, the lower is the energy content

Roule · October 5, 2015, 05:45

okay, got it, thanks a lot :-)

October 4, 2015, 22:53	what is the relation between size and strength of a large-scale eddy?	#1
Roule New Member Join Date: Jul 2013 Posts: 28 Rep Power: 12	hi, how is the strength of a large scale eddy related to its size. for example, suppose there are 2 large scale eddies - (1) one with dia. 10 cm and, (2) another with dia. 8 cm. which will have higher strength? it seems that the 10cm dia. is the answer, but is there any mathematical relation between size and strength of this eddy. also, which parameter is used for measuring eddy strength - vorticity or energy. it will be great if someone can suggest any relevant journal paper on this topic. i am asking this regarding turbulence in open channel flow. kaya likes this.

October 5, 2015, 05:45		#3
Roule New Member Join Date: Jul 2013 Posts: 28 Rep Power: 12	okay, got it, thanks a lot :-)