As the development of current propulsion technology such as gas turbine and
rocket chamber moving to higher working pressure, the radiative parameters of
fuel, such as CH4or CO, are required at elevated pressures, which in some
cases are calculated without considering the pressure effect of line broadening.
To investigate the pressure effect of line broadening on the radiative heat
transfer, the radiative heat sources of a one-dimensional enclosure filled
with CH4/CO and Planck mean absorption coefficients at elevated pressures were
calculated using the statistical narrow band(SNB)and line by line
(LBL)methods. The radiative parameters were conducted using high-temperature
molecular spectroscopic(HITEMP)2019 (for CO) and HITEMP 2020 (for CH4)
databases. The results showed that the pressure effect of line broadening on
the calculations of radiative heat source of CH4can be ignored when HITEMP
2020 database was used. For CO medium, the pressure effect of line broadening
was over 40% at 30 atm in all cases whichever methods and databases were used.
The pressure broadening has a strong effect on the Planck
mean absorption coefficient below 1000 K for CH4 and at the temperature of
500-900K for CO at 30 atm. The maximum pressure effects were 22% for CH4 and
18% for CO at 30 atm, which illustrated the pressure effect of line broadening
needed to be taken into account in the calculation of Planck mean absorption
coefficient.
Effect of pressure broadening on the radiative heat transfer by CO and CH4 gases using line by line method with latest high-temperature database