8.9.3. Point

8.9.3.1. PELVCONFIG: Elevated source selection file
8.9.3.2. PSTK: Point source stack replacement parameters file
8.9.3.3. PTMPLIST: List of hourly point source emissions files

The directories where the point-specific input files should be stored are listed in Table 8.10, “Point-Specific Input File Locations”. The table also lists the programs that use each input file.

8.9.3.1. PELVCONFIG: Elevated source selection file

The PELVCONFIG is optionally used by the Elevpoint program. It permits users to provide SMOKE criteria for grouping stacks and for selecting elevated and PinG point sources. “Stack groups” are groups of stacks from the same facility that are treated by SMOKE and the AQM as a single stack when computing plume rise and/or processing the stack as a PinG source. They have the effect of reducing the number of elevated and PinG stacks which makes for faster processing, particularly in the case of PinG sources in the AQM. Users can specify stack groups regardless of whether elevated or PinG sources are also being specified.

All emissions in a stack group are summed for the purposes of comparing against the elevated source criteria and PinG source criteria. In short, the grouped sources are treated as a single source for all SMOKE features regarding elevated source selection and special outputs. The grouped sources can still have different temporal profiles and chemical speciation profiles. For more information on how the emissions are computed for source selection, see Section 6.3, “Elevpoint.

The PELVCONFIG file has four sections: (1) source category selection, (2) source grouping, (3) PinG source selection, and (4) elevated source selection. Sections 2, 3, and 4 are optional, but Elevpoint will not run if all three sections are missing, because in that case the file would be instructing it to do nothing. The sections need not appear in any particular order, but each section is permitted only once. Comments may also be used in the file. The following subsections explain these major input features.

8.9.3.1.1. Using comments

Comments can be put in the file using a pound sign (#) in the first column of a line or a double pound sign (##) anywhere else in a line. For example, the double pound can appear after packet labels or instructions in the file.

8.9.3.1.2. Source category selection

This section is used to tell Elevpoint which source category to process. Since Elevpoint is designed only for point sources, this is very simple. This section needs to appear as follows:

SMK_SOURCE P

8.9.3.1.3. Source grouping

The /SPECIFY ELEV GROUPS/ packet is used for defining source groups based on source criteria. The packet contains the following entries:

  • /SPECIFY ELEV GROUPS/

    Must appear to start the packet. Only one packet of this type is permitted.

  • <Source grouping criteria, explained next>

  • /END/

    Must appear to end the packet.

The source grouping criteria can be as many lines as you want. Each line contains at least three parts: (1) variable (explained in Section 8.9.3.1.3.1, “/SPECIFY ELEV GROUPS/ variables”), (2) type of criterion (explained in Section 8.9.3.1.3.2, “/SPECIFIC ELEV GROUPS/ grouping criteria”), and (3) value for criterion, in the following structure:

<variable> <type of criterion> <value for criterion>

For example, the following source grouping criterion groups all inventory sources at the same facility that have stack heights within ±2 meters of weighted average stack height:

HT  +/-  2.0

The fact that sources are grouped by facility is implicit to the Elevpoint program, since we assumed when creating Elevpoint that grouping at a coarser level of detail was not desirable. The packet supports boolean OR and AND conditions. Each separate line of the packet is an OR condition. The AND conditions must appear on a single line. Any number of lines are permitted in this packet, as are any number of AND conditions or AND/OR combinations. However, each line has a maximum length of 300 characters.

The following example will help illustrate. To indicate that one group should consist of sources with stack heights within ±2 meters of weighted average stack height that also have diameters within ±1 meter of weighted average diameter, and that a second group should consist of sources with exit velocities below 10 m/s, the packet would be:

/SPECIFY ELEV GROUPS/
HT  +/-  2.0  AND  DIAMETER  +/- 1.0
VE  <  10.
/END/
8.9.3.1.3.1. /SPECIFY ELEV GROUPS/ variables

The elevated groups packet supports the following variables:

  • HT: stack height (m)

  • DM: stack diameter (m)

  • TK: stack gas exit temperature (K)

  • VE: stack gas exit velocity (m/s)

  • FL: stack gas exit flow rate (m3/s)

  • <pollutant name>: whatever pollutant names are in the inventory (e.g., NOX). We do not know why a user might want this type of grouping, but SMOKE does not prevent it.

8.9.3.1.3.2. /SPECIFIC ELEV GROUPS/ grouping criteria

The elevated groups packet supports the following types of grouping criteria:

  • +/- or -/+: variable values must be within plus or minus <value for criterion> for the variable given

  • >: variable values must be greater than <value for criterion> for the variable given

  • >= or =>: variable values must be greater than or equal to <value for criterion> for the variable given

  • <: variable values must be less than <value for criterion> for the variable given

  • <= or =<: variable values must be less than or equal to <value for criterion> for the variable given

  • = or ==: variable values must be equal to <value for criterion> for the variable given

  • %: variable values must be less than plus or minus <value for criterion> percent different for the variable given

8.9.3.1.4. Plume-in-grid source selection

The /SPECIFY PING/ packet is used for selecting plume-in-grid sources based on source criteria. The packet contains the following entries:

  • /SPECIFY PING/

    Must appear to start the packet. Only one packet of this type is permitted.

  • <Source selection criteria, explained next>

  • /END/

    Must appear to end the packet.

The source selection criteria can be as many lines as you want. Each line contains at least three parts: (1) variable (explained in Section 8.9.3.1.4.1, “/SPECIFY PING/ variables”), (2) type of criterion (explained in Section 8.9.3.1.4.2, “/SPECIFY PING/ selection criteria”), and (3) value for criterion in the following structure:

<variable> <type of criterion> <value for criterion>

This structure is the same as that of the /SPECIFY ELEV GROUPS/ packet, and the description of the PinG source selection criteria is the same as that of the source grouping criteria (see Section 8.9.3.1.3, “Source grouping”).

8.9.3.1.4.1. /SPECIFY PING/ variables

The PinG packet supports the same variables as the /SPECIFY ELEV GROUPS/ packet (see Section 8.9.3.1.3.1, “/SPECIFY ELEV GROUPS/ variables”) and the following additional variables:

  • RISE: The plume rise as computed by the Briggs algorithm documented with the Elevpoint program (see Section 6.3, “Elevpoint). The <value for criterion> must be provided in meters. To select all sources with plume rise greater than or equal to 75 meters, you would input:

    RISE >= 75.
  • SOURCE: Source number from the intermediate inventory file output by Smkinven. This variable permits selection of specific SMOKE sources as PinG sources.

  • PLANT: Plant ID code from the intermediate inventory file output by Smkinven. The “PLANT” variable can only be paired with the “IS” criterion type (below); no other criterion types (such as “<” or “=”) are permitted. It is recommended that this variable be used in addition to the FIPS variable (below) to allow selection of all records at specific plants. It can also be combined with stack parameter variables.

  • FIPS: Country/state/county region code. This can be used with the “PLANT” variable or other variables to specific PinG sources by region. It is not recommended that this variable be used alone for specifying PinG sources, because that would result in insignificant sources being prepared for the AQM as PinG sources. It does not make sense to process such sources as PinG sources in AQMs.

8.9.3.1.4.2. /SPECIFY PING/ selection criteria

The PinG packet supports the same types of criteria as the /SPECIFY ELEV GROUPS/ packet (see Section 8.9.3.1.3.2, “/SPECIFIC ELEV GROUPS/ grouping criteria”) and the following additional criteria types:

  • TOP: This criterion type permits users to select sources with the largest values of the variable given. The <value for criterion> is the number of sources that will be selected based on the value given. This criterion type is permitted only when using a pollutant name as the <variable>.

  • IS: This criterion type must be used to assign a value to the “PLANT” variable.

The following example illustrates a PinG packet that uses several of the variables and criterion types. In the following section is a further example that demonstrates using the rest of the variables and criterion types.

/SPECIFY PING/
RISE >= 150.
HT >= 100.
NOX TOP 100 AND SO2 TOP 100
NOX > 500.
/END/
8.9.3.1.5. Elevated source selection

The /SPECIFY ELEV/ packet is used for selecting elevated sources based on source criteria. The packet contains the following entries:

  • /SPECIFY ELEV/

    Must appear to start the packet. Only one packet of this type is permitted.

  • <Source selection criteria, explained above>

  • /END/

    Must appear to end the packet.

All of the source selection criteria for elevated sources are the same as the PinG selection criteria at this time (see Section 8.9.3.1.4, “Plume-in-grid source selection”). To use the “cutoff” method for UAM-style processing, only the “RISE” variable should be used; the packet should not contain any other selection criteria. The “cutoff” method is the traditional approach for elevated-source selection for UAM, UAM-V, REMSAD, and CAMX; you can decide if you want to use this traditional approach or a more complex set of criteria.

The following example illustrates using all of the different source selection variables and criterion types listed in the previous sections.

/SPECIFY ELEV/
RISE >= 40. AND RISE < 150.
NOX TOP 500
NH3 TOP 50
FIPS > 37001 AND FIPS <= 37031
SOURCE > 100 AND SOURCE < 200
/END/

8.9.3.2. PSTK: Point source stack replacement parameters file

The PSTK file is an ASCII file that contains the replacement stack parameters that Smkinven uses when stack parameters are missing from the inventory. The format of the file permits stack parameters to be replaced based on the point sources’ country/state/county code and SCC and is shown in Table 8.93, “Format for PSTK.

Table 8.93. Format for PSTK

Line Position Description
1+ A Country/State/County code (Integer)
  B Ten-digit SCC (Character)
  C Stack height from ground (m) (Real)
  D Stack diameter (m) (Real)
  E Stack exhaust temperature (K) (Real)
  F Stack exhaust velocity (m/s) (Real)

8.9.3.3. PTMPLIST: List of hourly point source emissions files

The PTMPLIST file is an list file containing the full name and path of available hourly point source emissions files. This file is created automatically from the example SMOKE run scripts. Its format is shown in Table 8.94, “Format for PTMPLIST.

Table 8.94. Format for PTMPLIST

Line Position Description
1+ A Full name and path of hourly point source emissions file