Projects per year
Abstract
The radiative heat transfer in a volatile hydrocarbon pool fire was investigated by obtaining the transmittance of infrared radiation through fuel (nheptane) layers of different depths. The incident radiation spectrum was assumed to be either the same as a spectrum obtained experimentally for a 2 me
ter pool fire, or to be a Planck distribution corresponding to the approximate flame temperature. The transmittances were calculated by integrating either the singleray LambertBeer formula, the twoflux method or the analytical planeparallel monochromatic/gray solution of the radiative transfer equation
over wavelength, using the liquid spectral absorption coefficients found in literature. The obtained results are validated against earlier measurements, and the possibility of calculating them with significantly less computation time by using a kdistribution method was investigated. The results managed to replicate the measured heat flux values in the liquid with a fractional error of only about 5% being attainable even with a 3point quadrature method. The use of the kdistribution, more known and used in gas phase thermal radiation calculations, significantly speeds up the calculations. It was found out that in the
calculation of total transmitted fractions of radiation, the flame spectrum can be approximated with a Planck distribution of an appropriate temperature.
ter pool fire, or to be a Planck distribution corresponding to the approximate flame temperature. The transmittances were calculated by integrating either the singleray LambertBeer formula, the twoflux method or the analytical planeparallel monochromatic/gray solution of the radiative transfer equation
over wavelength, using the liquid spectral absorption coefficients found in literature. The obtained results are validated against earlier measurements, and the possibility of calculating them with significantly less computation time by using a kdistribution method was investigated. The results managed to replicate the measured heat flux values in the liquid with a fractional error of only about 5% being attainable even with a 3point quadrature method. The use of the kdistribution, more known and used in gas phase thermal radiation calculations, significantly speeds up the calculations. It was found out that in the
calculation of total transmitted fractions of radiation, the flame spectrum can be approximated with a Planck distribution of an appropriate temperature.
Original language  English 

Pages (fromto)  11011109 
Number of pages  9 
Journal  International Journal of Heat and Mass Transfer 
Volume  127 
DOIs  
Publication status  Published  1 Dec 2018 
MoE publication type  A1 Journal articlerefereed 
Keywords
 spectral radiation
 kdistribution
 liquid nheptane
 pool fire
 numerical modeling
Fingerprint Dive into the research topics of 'Spectrally resolved calculation of thermal radiation penetration into liquid nheptane in pool fires'. Together they form a unique fingerprint.
Projects
 1 Active

Novel measurement and sensing technologies for thermal radiation of unwanted fires
Hostikka, S., Isojärvi, T., Bordbar, H., Lunkka, J. & Naji Nassajfar, M.
01/01/2018 → 31/12/2021
Project: Academy of Finland: Other research funding