PROGRAM
IDEI – CERCETARI EXPLORATORII
Cod Proiect
ID_1103 / 2008

Director
Proiect: Florin SPINEANU

Investigarea prin metode de teorie de camp a structurilor si a autoorganizarii in
fluide si plasma 
PROJECT SUMMARY

Experimental,
numerical and theoretical studies have revealed that the twodimensional
fluids and plasmas exhibit an intrinsic evolution
to organisation. This is
most obvious at relaxation from turbulent states when the system evolves
toward a reduced subset of flow patterns, characterized by a regular form of
the streamfunction (coherent structures). This problem is common to the ideal
incompressible (Euler) fluid, to plasma in strong magnetic field, to
nonneutral plasmas, to planetary atmopshere, MHD, etc. The equations
governing the asymptotic stationary, highly ordered states, for any of these
systems, could not be derived (for the Euler fluid the sinhPoisson equation
has been inferred from numerical studies). Except for a limited success in
applying statistical considerations, there is no conceptual basis on which to
develop an analytical approach for this problem. The 2D ideal
(Euler) fluid and the 2D magnetized plasma (and planetary atmosphere) are
equivalent with discrete systems consisting of sets of pointlike vortices
interacting in plane by a potential. We found that the continuum limit of
these discrete models can be formalized in terms of a Lagrangian density,
preserving the structure: matter (pointlike vortices), field (from
potential) and interaction between them. The result is a classical field
theory from which we derive the equations of motion and look for stationary
states that correspond to the lowest action. The first applications to
practical cases are very encouraging when compared with the experiment. The development and the
applications of field theoretical formulations in order to highlight the
intrinsic trend to selforganization in fluids and plasmas is almost without
precedent, therefore the Project will treat a really new subject of research.
If successful, this will represent a considerable change in our understanding
of the fluid physics, in the concepts and terms to formulate new theories on
fluids, and in our technical methods.

PROJECT OBJECTIVES



Associated international
project 
Participation to COST Action ES0905 “Basic
Concepts for Convection Parameterization in Weather Forecast and Climate
Models” The main objective of
the Action is to provide clear theoretical guidance on convection
parameterizations for climate and numerical weather prediction models. Both
global and regional atmospheric models are concerned. The Action achieves
this objective by creating a core theoretical group to address the
fundamental issues of convection parameterization. Modellers and
theoreticians join together under this framework. The Action proposes a clear
pathway for more coherent and effective parameterizations by integrating
existing operational schemes and new theoretical ideas. Proposed alternative
approaches intend to replace conventional tuningbased approaches. The Action
complements extensive intercomparison based validations performed by
operational modellers.The Action responds particularly to urgent needs which
have arisen from increasing the resolutions of forecast models. In these
newgeneration models, not only the traditional approximations break down,
but associated physical processes become increasingly complex. Thus, the
parameterization must be extensively reformulated with more sophisticated
physics under new constraints. The Action contributes to reduce uncertainties
in weather forecasts and climate projection by overcoming the often weak
physical basis of the current parameterizations. Particular benefits will be
in prediction of highly unusual extreme weather events, such as local heavy
precipitation, tropical cyclone trajectories etc. The IPCC will be a
particular international agent that will benefit from the present Action. 