16. PROFILE

User Guide MAIN MENU

General introduction

PROFILE is a utility for post-processing the results files produced by AEROPLUME and PGPLUME, creating output files for submission to suitable user-selected plotting packages. PROFILE creates data to plot concentration contours assuming a Gaussian concentration profile perpendicular to the plume-axis.

PROFILE was not available in versions of HGSYSTEM previous to version 3.0.

PROFILE is run in an identical manner to other HGSYSTEM programs using the batch file PROFILE.BAT.

Range of applications and limitations

The post-processor can handle any AEROPLUME report file, having a DOS filename 'casename.APR', and any PGPLUME report file, having a DOS filename 'casename.PG1', where 'casename' is the user-supplied name of the problem. If only one of the files 'casename.APR' or 'casename.PG1' exists, this is taken as the sole input for post-processing purposes, while if both exist, both are used.

Note that if AEROPLUME and PGPLUME have been run separately using the same 'casename', the utility will combine the data of both result files even if there is no meaningful connection between the two simulations.

PROFILE will only produce contours for that part of the plume which is airborne.

As the program considers slices through a plume, if the axis inclination changes rapidly the slices may overlap relatively near to the centroid, the result being contours that cross each other.

Guidance for use

When first used to post-process AEROPLUME and/or PGPLUME output for a new case, it is recommended that most of the input data is not specified by the user, but allowed to take default values. Such usage has the advantage of requiring little if any data analysis by the user, enabling automatic running of the post-processor and the rapid production of an initial set of output files. Further refinement of the input data can then be made in a meaningful manner and the exact output requirements finalised for the current case.

This does not of course apply where the user is interested in exact values, such as when producing iso-concentration plots at lower and upper flammability limits, where it would obviously make sense to specify the required values in the contour input block.

PROFILE INPUT FILE PARAMETERS

A description of all the input parameters that can occur in a PROFILE input file will be given.

The PROFILE input file has the DOS filename 'casename.PRI', where 'casename' is the user-supplied name of the problem and must match that used for the original AEROPLUME run which produced the result file 'casename.APR', and/or the original PGPLUME run which produced the result file 'casename.PG1'.

A standard report file 'casename.PRR' containing a summary of the input from AEROPLUME and/or PGPLUME is always produced. If the other two output files contain little or no data, reference to the '.PRR' file should enable the user to alter the required contour value or horizontal height so as to obtain useful results.

In the following, actual keywords are given in capitals and in bold. The descriptions of less important parameters or parameters that need not normally be set by the user, are given in a smaller font.

All parameters, except TITLE, occur in blocks preceded by a specific block keyword. For PROFILE these block keywords are: CONTOUR and AVTIMC.

The TITLE keyword does not occur in a parameter block.

TITLE The title of the current problem to be run with PROFILE.
  At most 50 alphanumeric characters.
  Optional, no default.

The CONTOUR block specifies the parameters to produce 2 output files containing data to generate iso-concentration contour plots at a user-specified concentration.
The file 'casename.PRH' gives downwind distance versus lateral displacement for a horizontal plane at a user-specified height.
The file 'casename.PRV' gives 2 pairs of downwind distance versus height values for a vertical centre-line plane.

CMINC Required contour value (%).
  1.0E-05 <= CMINC <= 100.0.
  Mandatory, no default.
ZC Constant value z for horizontal contour plane xy (m).
  0.0 <= ZC <= 1.0E06.
  Optional (default 0.0).

AVTIMC keyword does not occur in a parameter block. If the keyword is used a time-averaging correction is applied to the results file input data. Any such correction takes place before the processing of other data blocks and affects the results written to the output files.

AVTIMC Averaging time for concentrations (s).
  18.75 <= AVTIMC <= 600.
  Optional, default is 18.75 (no time averaging).
  Note: it is assumed by PROFILE that all PGPLUME generated results are for an 'instantaneous' plume, that is for an averaging time of 18.75 s or less. If the user wants to apply time-averaging during the PROFILE run then the appropriate value of AVTIMC should be set here but not in the PGPLUME input file.

User Guide MAIN MENU