Emergence in natural porous media


Organisationseinheit:
Lehrstuhl für Angewandte Mathematik

FAU Kontaktperson:
Ray, Nadja Dr.
Prechtel, Alexander Dr.
Rupp, Andreas
Kräutle, Serge PD Dr.

Beschreibung:

The grand goal of this group is the
development, analytical, and numerical investigation of a mechanistic
model describing processes of formation, stability, and turnover of soil
micro-aggregates, i.e., particles in the range up to 250 micrometers.
In contrast to existing conceptual aggregation models and compartment
models for carbon turnover and aggregation, we focus on specific,
experimentally identified transformation processes of soil
microaggregates.
Since we are interested in giving an improved
mechanistic, qualitative and even quantitative description of
aggregation, we transfer the gained insights of 1. to a mechanistic
model in terms of ordinary differential equations (ODEs), partial
differential equations (PDEs), and perhaps algebraic equations (AEs). To
that end, we aim to take into account information/identified processes
on different spatial scales as well as spatial heterogeneity and
variability. All our modeling is done in a rigorous, deterministic way
and our modeling concepts are based on continuum mechanics, i.e. a
description via concentrations and not a description considering single
particles. We start our investigations at the pore scale and apply
multiscale techniques to obtain a comprehensive mathematical model at
the macroscale (bottom up). In particular, the interplay of geochemistry
and microbiology is considered, and also their link to soil functions.

The
coupled ODE/PDE systems and complex micro-macro problems can not be
treated numerically with standard software packages. The number of
species, nonlinearity of the processes and heterogeneity of the medium
results in a high computational effort that requires accurate and
efficient discretization methods and solution algorithms. Moreover
sophisticated numerical multiscale methods have to be applied.
In
our simulations, we do not aim to recreate reality in every detail.
Instead, we aim to illustrate, compare, and reveal influencing factors
and mechanisms by abstracting relevant processes.


Forschungsprojekt(e)


(DFG RU 2179 “MAD Soil - Microaggregates: Formation and turnover of the structural building blocks of soils”):
Mechanistische Modellierung der Formation und Konsolidierung von Mikroaggregaten in Böden
Dr. Alexander Prechtel; Dr. Nadja Ray
(01.01.2016 - 31.12.2019)

Zuletzt aktualisiert 2019-02-04 um 00:02