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Division 3.3.1 Dry air and chemical species

United Kingdom

Original text. Later amendments are not shown.

This section uses the following values for dry air composition:

  • x O2airdry = 0,209445 mol/mol

  • x Arairdry = 0,00934 mol/mol

  • x N2airdry = 0,78084 mol/mol

  • x CO2airdry = 375 μmol/mol

This section uses the following molar masses or effective molar masses of chemical species:

M air

  • 28,96559 g/mol (dry air)

    • M Ar

  • 39,948 g/mol (argon)

    • M C

  • 12,0107 g/mol (carbon)

    • M CO

  • 28,0101 g/mol (carbon monoxide)

    • M CO2

  • 44,0095 g/mol (carbon dioxide)

    • M H

  • 1,00794 g/mol (atomic hydrogen)

    • M H2

  • 2,01588 g/mol (molecular hydrogen)

    • M H2O

  • 18,01528 g/mol (water)

    • M He

  • 4,002602 g/mol (helium)

    • M N

  • 14,0067 g/mol (atomic nitrogen)

    • M N2

  • 28,0134 g/mol (molecular nitrogen)

    • M NOx

  • 46,0055 g/mol (oxides of nitrogen (*))

    • M O

  • 15,9994 g/mol (atomic oxygen)

    • M O2

  • 31,9988 g/mol (molecular oxygen)

    • M C3H8

  • 44,09562 g/mol (propane)

    • M S

  • 32,065 g/mol (sulphur)

    • M HC

  • 13,875389 g/mol (total hydrocarbon (**))

    • This section uses the following molar gas constant R for ideal gases:

    R = 8,314472J (mol · K)

    This section uses the following ratios of specific heats γ [J/(kg · K)]/[J/(kg · K)] for dilution air and diluted exhaust:

    γ air

  • 1,399 (ratio of specific heats for intake air or dilution air)

    • γ dil

  • 1,399 (ratio of specific heats for diluted exhaust gas)

    • γ exh

  • 1,385 (ratio of specific heats for raw exhaust gas)

    1. (**)Division (**)
    2. (*)Division (*)