Below you will find a series of movies that have been taken at different times over a period of some forty years. If you want to know more about the scientific content of each movie click on the “more info” top right hand corner marker for each movie. Below the movie in most cases you will find the scientific reference that relates to the work.

Carbon Nanotubes (CNTs) were all the rage in the 2000s and now have found niche rather than widespread application. This remarkable movie taken by Anson Ma shows how CNTs can aggregate during shear to form helical banding. The Movie was taken using a Linkam Cambridge Shear Cell and is an example of “expect the unexpected”, but seeing is believing!

Carbon Nanotube (CNT)  aggregate Helical banding. Anson Ma 2005

Experimental observation on the flow-induced assembly of Carbon nanotube suspensions to form helical bands

In the 1990s I discovered that chocolate could be “cold extruded” and there was an exciting period at Cambridge where we pursued the science behind the concept and Nestle explored the commercial potential.

The movie below shows how chocolate can be “cold extruded” below its normal melting point using reasonably high pressure ( 200bar) ram extrusion,

 Chocolate Cold  Extrusion.  Yu Wen Chen. 2000s

Flexible chocolate.

Cold extruded Flexible chocolate being tied in knots. Yu Wen Chen 2000s

Flexible chocolate.

Injection moulding of cold extruded  chocolate 1990s 

Flexible chocolate.

The “Ovaci Necklace ” chocolate extrusion instability 2000s 

The experimental observation and modelling of an “Ovaici”necklace and stick-spurt instability arising during the cold extrusion of chocolate.

Tomorrows World”, Flexible chocolate 1996

The effect of shear on carbon black aggregates. Kat Yearsley 2009

The rheology of multi-walled carbon nanotube and carbon black suspensions

Flow birefringence within a Cross Slot geometry. David Hassell 2005

Cross-slot extensional flow birefringence observations of polymer melts using a multi-pass rheometer

8hz 3mm 01Lmin

multi slugs

F10A1 ave vm f2

F10A2 resize 5

Minghzi LES

Flow splitting attempt Mineral oil water with 0 8mm needle

slug generation upstream

Osc Flow Adam Harvey 1995

DOW150R DGH3 160C 1mms 30 450