gas_mix

Purpose:

Compute the gas composition of a stream which is produced by mixing two or more gas streams. The composition and mass flow of each of the input streams must be known and specified. The resulting mixed stream composition and mass flow are the outputs of this application.

Enter:

gas_mix <priority> <interval> <filename> [+c] &

Where:

priority

Specify the system task priority.

interval

Specify the time interval or rate to perform the calculations. Specify one of the values supported by the scheduler as specified in the go script. Specify SLO, MED, or FAS.

filename

Specify the spec filename to read that contains the specifications of the gases that are to be mixed.

+c

Optional. Specify this flag to indicate a critical watchdog task. A flag indicating that this process should be registered as a critical task. The default is to leave the task as non-critical.

Example:

gas_mix 12 1000 /specs/properties/mix_specs.111 &
The above command sets the priority of the process to be 12 and performs the computations at the rate of once every second. The spec file mix_specs.111 is read to determine the gases to be mixed, the output stream composition, and mass flow.  The gas_mix task will register it’s name with the filename (not the full pathame), in this case “mix_specs.111”.  This name can be used by the ‘re-read’ command to request that it update the specifications by reading the specification file again.  This feature allows the specifications to be changed “on-the-fly” without slaying and restarting the app. Note: re-read feature is not available prior to 6.3.30 or 6.4.0.

################################ spec file  ###################  
## line 1:  identify the output stream composition file and output stream  
##          mass flow variable  
##  
##          These 2 variables are ‘output’ variables – they will be  
##          modified by the gas_mix application  
##  
##Output Stream  
##composition                  massflow  
faC.                          fa_mf  
## line 2-n Identify the input streams which are being mixed – There must be  
##          a composition variable and mass flow for each stream, so the number  
##          of streams which can be mixed is limited by the current maximum  
##          number of composition types (~20).  
##Input Streams- this is a list of the streams that are being mixed  
##               (1 line per stream)  
##composition                  massflow  
##                             (NOTE:  massflow variable may be either a  
##                              REAL or STATISTICAL variable )  
inlet_airC.                   air_mtr0_mf  
ngC.                          ng_mf  
###################################################################

Notes:

This process computes gas composition by mixing on a continuous basis and is normally started via the go script.

See Also:

Determining Gas Mixture Composition, Computing Gas Stream Composition and Mass Flow