The workshop 'Direct and Large-Eddy Simulation-4' was held at the Uni-
versity ofTwente, July 18-20, 2001. DLES4is part of a series ofERCOFfAC
workshops that originated at the University of Surrey in 1994. Over the
years the DLES-series has grown into a major international venue focused
on the development and application of direct and large-eddy simulation.
Fundamental turbulence - and modeling issues but also elements from
modem numerical analysis are at the heart of this field of interest, a
fact which is clearly reflected by the contents of these proceedings.
Modeling and simulation of complex flow phenomena forms a central ele-
ment in a large volume of scientific - and applied research. The problem
of simulating turbulent flows and capturing their main dynamical
features remains a highly motivating challenge. This three-day workshop
focused on recent de- velopments in numerical and physical modeling of
complex flow phenomena concentrating on modem strategies in the field of
direct and large-eddy simula- tion. A major aim was to promote the
exchange of ideas and problems from both industrial and academic
background paying attention to physical, mathematical and engineering
aspects.
