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Dynamics of Thread Movement in Turbulent Flow Field James Hallendorff Suman Sinha Ray Alexander L. Yarin
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Page 1: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Dynamics of Thread Movement in Turbulent

Flow FieldJames HallendorffSuman Sinha RayAlexander L. Yarin

Page 2: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Investigate instability mechanism in melt blowing

Motivation

Page 3: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Used to measure Lagrangian motion

Initial setup

Page 4: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Lagrangian Results

Page 5: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Lagrangian Results

Page 6: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Eulerian Behavior

Page 7: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Fast Fourier Transform

Eulerian Results

Page 8: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

FFT Results

Page 9: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Harmonics Many harmonics, few that make a difference

Page 10: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Is This Chaotic??

Page 11: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Determine correlation between string length and snapping length or air velocity and snapping length

Snapping Point

Page 12: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Gravity causes artificial snapping point-makes unreliable results

New setup

Snapping point error

Page 13: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Vertical Setup

Page 14: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

5 10 15 20 25 30 350

2

4

6

8

10

12

30 Bar String Length vs. Snap Length

3.5x

String Length

Snap L

ength

Page 15: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Width to Length Ratio

Page 16: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Using a fixed-length criteria skews results Compare ratios of width to snapping length

Revised Measurement Strategy

8 10 12 14 16 18 20 220

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

Calculated RatioJudgment Ratio

String Length

Rati

o

Page 17: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

Use the frequencies found in the FFT to augment theoretical model

Analyze the movement of the string in a vertical position

Use polymer solution to simulate melt blowing and to compare it to the thread movement model

Future Work

Conclusion: 2 months is not enough

Page 18: James Hallendorff Suman Sinha Ray Alexander L. Yarin.

"MELT BLOWN TECHNOLOGY." UT Knoxville | College of Engineering. Web. 16 July 2009. <http://www.engr.utk.edu/mse/pages/Textiles/Melt%20Blown%20Technology.htm>.

EEC-NSF Grant #0755115 Dr. Takoudis Dr. Jursich Qian Tao

Acknowledgements