Temperature Initialization in sopale_nested

Douglas Guptill

douglas.guptill@dal.ca

August 6, 2010

1 Introduction

We describe how the initial temperatures are determined in sopale_nested. By "initial", we mean before time stepping starts. These temperatures are in the ``f98'' output file.

1.1 Notation

The sopale_nested input file has parameters which are in grouped in sections. Each section has a $\fbox{name}$ .

2 Lagrangian Temperatures

Lagrangian temperatures can be specified in the $\fbox{LTEMP}$ and $\fbox{LPERTURB-T}$ ¹sections of the input file. However those temperatures are never used in any calculations. They will appear in the output files if those are written at time step one.

Subsequently, all Lagrangian temperatures are determined, from Eulerian temperatures, in the ALE loop. The temperature of existing particles is interpolated from the temperatures of four corners of their Eulerian cell. The temperature of injected particles is either the average temperature of all other Lagrangian particles in the cell (if e_temperature = 0) or the Eulerian cell temperature.

3 Eulerian Temperatures

There are sequential, often independent, calculations of the Eulerian temperatures. In some cases, one calculation overwrites a previous one.

3.1 As in $\fbox{ETEMP}$

The parameters in $\fbox{ETEMP}$ define the Eulerian temperature field on the Eulerian grid nodes. This is the first calculation.

3.2 `type_bct0`

If type_bct0 = 0, the $\fbox{ETEMP}$ temperatures are left undisturbed at this stage. If type_bct0 = 3, the $\fbox{ETEMP}$ temperatures are overwritten by the results of a steady-state calculation.

3.2.1 `type_bct0=3`

If type_bct0 = 3, there is a steady-state calculation of the Eulerian temperatures. The results overwrite the $\fbox{ETEMP}$ temperatures.

The steady-state calculation of temperature needs a starting value. This starting value can be either

temperature_initial, if that is positive, or
the existing temperature values, as calculated from $\fbox{ETEMP}$ .

The steady-state temperature calculation iterates²

as long as there are any materials that have a temperature-varying conductivity³.
until the maximum temperature change does not exceed maxter_i.
until the maximum number of iterations (max_th_iters) is exceeded.

3.3 $\fbox{EPERTURB-T}$

If the $\fbox{EPERTURB-T}$ ⁴ section exists in the input file, the parameters in it are used to redefine the Eulerian temperatures. Existing values are overwritten.

3.4 `ntperts`

An arbitrary number of boxes are defined (by the user, in the input file) on the Eulerian grid. A temperature increment is associated with each box, and added to the Eulerian temperatures.

About this document ...

Temperature Initialization in sopale_nested

This document was generated using the LaTeX2HTML translator Version 2002-2-1 (1.71)

The command line arguments were:
latex2html -split=0 -show_section_numbers AboutTemperatureInit.tex

The translation was initiated by Douglas Guptill on 2010-08-06

Footnotes

...#tex2html_wrap_inline69#¹: Introduced in version 2009-07-26_22
... iterates ²: Introduced in version 2009-07-26_10 and 11
... conductivity ³: Introduced in version 2009-07-26_10
...#tex2html_wrap_inline117#⁴: Introduced in version 2009-07-26_22

Douglas Guptill 2010-08-06