R I C H Y 1D

Abstract

RICHY1D is a simulation software for physical transport problems modelled by partial differential equations. RICHY1D

  • works in 1 spatial dimension,
  • simulates time and space dependent problems,
  • includes the solution of inverse problems to identify model parameters
  • ... and provides many more features for mathematicians and engineers, described within this manual.

RICHY1D's main purpose is to support the evaluation of soil RemedIation and RIsk assessment scenarios. A typical situation of interest is a Contaminated site, where the spreading of CHemicals in the soil exhibits a Hazard for the environment. Model equations for (un-)saturated water flow and for solute transport were the first problems of HYdrology, numericallY

solved with RICHY1D

"The application of natural attenuation as a site remediation strategy depends essentially on the reliable prediction of the migration of the contaminant plume.
[RICHY1D is] a one-dimensional simulation tool that is capable of handling a variety of complex scenarios predicted to be of interest in site remediation problems.  The implementation of the different components is organized in a modular structure that facilitates arbitrary extensions of the incorporated models and enables the model components to be combined.  Efficient, robust numerical techniques (e.g. hybrid mixed finite elements) are embedded in a menu driven, user-friendly environment to serve hydrogeologists or engineers without profound knowledge of the mathematical theory.  The software is suitable for Unix workstations as well as inexpensive personal computers.  The model components include reactive solute transport (with diffusion, dispersion, advection and sorption) and single- as well as two-phase flow in the saturated and the vadose zone.  The underlying models contain non-standard effects that enable the simulation of a large variety of relevant support strategies for natural attenuation."
[E. SCHNEID, A. PRECHTEL, P. KNABNER.  A Comprehensive Tool for the Simulation of Complex Reactive Transport and Flow in Soils.  Land Contamination & Reclamation, 8(4):357-365, 2000.]

The following processes can be modelled and simulated with RICHY1D:

- Water flow in the saturated and vadose zone including preferential flow
- Reactive solute transport with diffusion, dispersion, advection and sorption including equilibrium isotherms and multiple site kinetics
- Carrier facilitated transport
- Biodegradation with biomass dynamics, multiple monod kinetics and inhibition terms
- Coupled water and surfactant transport
- Heat transport including temperature dependant degradation reactions for solutes
- General stoichiometric reaction kinetics
- Mineral dissolution and precipitation

The majority of the above problem classes can be used with inverse modelling routines to identify unknown parameters through various parameter identification algorithms. On the basis of experimental data, e.g. the breakthrough curve of a column experiment, unknown model parameters are identified even simultaneously.

Example simulations for each problem class lead to the corresponding settings.

The underlying numerical algorithms are state-of-the-art techniques of modern mathematics, including mixed hybrid finite element methods, adaptive grid strategies, fully implicit coupling of transport and reaction problems and more where necessary.

RICHY1D is used interdisciplinarily by research institutes in mathematics and the geo sciences, consultants, and authorities as well.

GUI

RICHY1D's GUI is built with Tcl/Tk to maintain portability.  Have a look at the following screenshot done on a Windows7 OS:

Documentation

The entire documentation is available as a linked pdf.  The links are organized in a way that it can be used similar to a web page — by clicking the section- or equation names etc. and using the back button — or as a printable book as the links refer to pages.  Manual RICHY1D.pdf

RICHY 2D/3D

See also: RICHY2D/3D.html