Scattering techniques are advancing knowledge of structural changes an
d phase behaviour in flowing systems; this information increases our u
nderstanding of rheological behaviour. Studies of sheared fluids at su
rfaces and experiments with synchrotron X-ray scattering on thin films
are showing potential in the investigation of novel flow geometries.
Experiments can now quantitatively test theoretical models and have, f
or example, highlighted the importance of hydrodynamic interparticle f
orces.