TY - JOUR
TI - Nusselt number evaluation for combined radiative and convective heat transfer in flow of gaseous products from combustion
AU - Trabelsi Soraya
AU - Lakhal Wissem
AU - Sediki Ezeddine
AU - Moussa Mahmoud
JN - Thermal Science
PY - 2013
VL - 17
IS - 4
SP - 1093
EP - 1106
PT - Article
AB - Combined convection and radiation in simultaneously developing laminar flow  and heat transfer is numerically considered with a discrete-direction method.  Coupled heat transfer in absorbing emitting but not scattering gases is  presented in some cases of practical situations such as combustion of natural  gas, propane and heavy fuel. Numerical calculations are performed to evaluate  the thermal radiation effects on heat transfer through combustion products  flowing inside circular ducts. The radiative properties of the flowing gases  are modeled by using the absorption distribution function (ADF) model. The  fluid is a mixture of carbon dioxide, water vapor, and nitrogen. The flow and  energy balance equations are solved simultaneously with temperature dependent  fluid properties. The bulk mean temperature variations and Nusselt numbers  are shown for a uniform inlet temperature. Total, radiative and convective  mean Nusselt numbers and their axial evolution for different gas mixtures  produced by combustion with oxygen are explored.