burn_emis

Purpose:

Calculate burned gas emission

Enter:

burn_emis <priority> <filename> [+c] &

Where:

priority	Specify the task priority that the operating system should assign to this task.
filename	Specify the path of the specifications file for the burned gas emission calculations.
+c	Optional. Specify this flag to register this task as a critical task with the master scheduler. A SLO rate is assumed as the interface period to the master scheduler.

Example:

burn_emis 13 /specs/emis_specs.115 +c &
The above would spawn the task burn_emis with a priority of 13 and the file /specs/emis_specs.115 contains the specifications for the burned gas/emission calculations. The task will be registered as critical with the master scheduler.

Notes:

   This task is normally started in the go script as part of the
         CYFLEX startup process.

         For more information see Cummins intranet url:

            /asset.ctc.cummins.com/asset/tte/gas_comp_prop/
               back_fire.pdf
            /asset.ctc.cummins.com/asset/tte/gas_comp_prop/
               burned_gas_comp.pdf
            /asset.ctc.cummins.com/asset/tte/gas_comp_prop/
               gaseous_emissions.pdf
            /asset.ctc.cummins.com/asset/tte/gas_comp_prop/
               new_balances.pdf

   The following is an example specification file for burn_emis.

# %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
#
#                                emis_specs_rt.nnn
#                                       or
#                                emis_specs_fr.nnn
#
# %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
#
#  This is a specification file for the “burn_emis” task.  For details
#  on using burn_emis, type “use burn_emis” on the command line.
#
#  Several different instances of the “burn_emis” task can be running at
#  the same time.  Often one will be setup to perform burned gas
#  composition and emissions calculations in real time to provide
#  feedback and another instance will be synchronized with a fuel
#  reading.
#
#  Throughout this file, we will use the default fuel reading labels but
#  will include the labels associated with real time measuements as a
#  commented line. The actual name of this file should be altered as
#  shown in the header to reflected the contents.
#
#  The @REG_NAME keyword is used to distinguish between instances.  We
#  strongly recommend using “burn_emis_rt” as the registered name to
#  designate the real time instance and “burn_emis_fr” to indicate the
#  instance associated with a fuel reading.

# %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   @REG_NAME
      burn_emis_fr
  #   burn_emis_rt

# %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

#  The @COMPUTE_EVENT keyword is used to specify the event or timer
#  interval that will be used to trigger the calculation and the event
#  that will be emitted when the calculation is complete.  The
#  calculation done event can be used to ‘‘cascade’’ a series of
#  calculations, most notably those associated with egr.

# %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   @COMPUTE_EVENT
    #  start event name or            done event name
    # continuous intrvl name
        fr_done                         FR_emisCalcDone
    #    SLO                             burn_emis_done_rt

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   #  The @BURNED_STREAM keyword is used to specify two outputs and one
   #  input. The burn_emis task will load the calculated composition into
   #  the composition variable specified by the first entry.  The
   #  calculated burned gas mass flow rate will be loaded into the variable
   #  specified by the second entry.  The third entry, the temperature of
   #  the burned gas stream, will be used as an input only in the case of
   #  rich combustion and can be safely set to a measured temperature such
   #  as tur_ot_t or exh_stk_t if you are burning lean as all good diesels
   #  do.  The proper temperature to use for rich combustion is a topic
   #  that should be discussed and throughly understood before being used
   #  blindly.

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   @BURNED_STREAM
      # composition label     mass flow label      burned gas temperature
        FR_BurndGasC.         FR_burned_gasMF      tur_ot_t
   #     burn_gas_rtC.         burn_gas_mf_rt       tur_ot_t

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   #  The @INPUT_STREAMS keyword is used to provide a list of the
   #  composition variables and mass flow rates that define the various
   #  input streams. Because the number of input streams is not limited,
   #  this list is ended with a “$” as the final entry.
   #
   #  Typically, there are two streams specified; fuel and combustion air.
   #  For test cells equipped with a balance type fuel scales, fuel rate
   #  measurements are only available after the completion of a fuel
   #  reading. Real$-$time burned gas composition calculations must be based
   #  either on and estimated fuel rate, usually defined as a funtion of an
   #  ECM commanded fueling, or based on a measured exhaust gas
   #  concentration of either oxygen or carbon dioxide.
   #
   #  If a measured exhaust gas concentration is used, the mass flow rate
   #  of the fuel becomes an output and is specified as such by preceding
   #  the label name with a “>”.  An example is provided below as a
   #  commented line.  The measured exhaust gas concentration that is to be
   #  used for this calculation should be specified by preceding the label
   #  with a “<” under the @MEASURED_CONCENTRATIONS keyword as described
   #  below.
   #
   #  This feature is not limited to the fuel stream.  It can be used on
   #  one and only one of the input streams in the list.
   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   @INPUT_STREAMS
      #  composition          mass flow
      # variable label      variable label
        ngC.                FR_Fuel_rate
        inlet_airC.         FR_air_mf

   #     diesel_certC.       >fuel_rate_co2
   #     diesel_certC.       fuel_rate_calc
   #     inlet_airC.         air_mtr0_mf

   $

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   #  The @MEASURED_CONCENTRATIONS keyword is used to specify the labels
   #  for names of the variables that contain the measured or calculated
   #  exhaust gas concentrations of CO2, CO, NOx, O2, HC and H2O.  The
   #  identity of the component is specified using the letter identifiers
   #  CD_CO2, CD_CO, CD_NOX, CD_O2, CW_HC, CW_H2O, CW_O2, CW_CO2, CW_CO,
   #  CW_AMMONIA, CW_METHANE, CD_METHANE for various wet or dry
   #  concentrations. Because the number of measured concentrations is not
   #  fixed, this list is ended with a “$” as the final entry.
   #
   #  Preceding a label with a “<” indicates that the measured
   #  concentration is to be used to back$-$calculate the flow rate
   #  indicated with a “>” under the @INPUT_STREAMS keyword above.  Only
   #  one label at a time may be used and it must be either CO2, O2 or H2O.
   #
   #  The H2O concentration is not often measured, but is included here
   #  primarily as an input to be used as a way to calculate the fuel/air
   #  ratio that would produce a give water vapor concentration in the
   #  exhaust, usually one that would be sufficiently high to cause
   #  condensation in an egr cooler at a given temperature.
   #
   #  This is an optional keyword and is not needed if the desired
   #  calculations do not include the emissions calculations. In addition,
   #  if a particular concentration is not being measured that entry may
   #  be omitted.

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   @MEASURED_CONCENTRATIONS
      # selected component   concentration label
        CD_CO2               CO2_Conc_pct.AV
        CD_CO                CO_Conc_ppm.AV
        CW_NOX               NOx_Conc_ppm.AV
        CD_O2                O2_Conc_%.AV
        CW_HC                HC_Conc_ppm.AV
   #     CW_H2O               exh_cd_h2o_mea.AV

   #     CW_H2O               <exh_cd_h2o_mea
   #     CD_CO2               <exh_cd_co2_mea

   # new keywords for selected component will be
   #     CW_CO2               $-$$-$
   #     CW_CO                $-$$-$
   #     CW_O2                $-$$-$
   #     CW_AMMONIA           $-$$-$
   #     CW_METHANE           $-$$-$
   #     CD_METHANE           $-$$-$
   $

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   #  The @POWER keyword is used to specify the variable for the brake
   #  horsepower reading needed to calculate brake specific emissions
   #  based on measured exhaust gas concentrations.
   #
   #  This is an optional keyword and is not needed if the desired
   #  calculations do not include the emissions calculations.

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   @POWER
      # horsepower label
        FR_BHP
   #     Dyno_power

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   #  The @EMISSION_RESULTS keyword is used to specify the emissions
   #  variable name that will be used to output the results of any
   #  emissions calculations.
   #
   #  This is an optional keyword and is not needed if the desired
   #  calculations do not include the emissions calculations.

   # %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

   @EMISSION_RESULTS
      # emission variable label
        FR_exhE.
   #     exh_frE.

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