HEAD LOSSES IN DUCT FLOWS WITH CONDUCTION-RADIATION HEAT TRANSFER

Deodat Makhanlall¹

¹ Anton de Kom University of Suriname (AdeKUS)

doi:10.20906/CPS/COB-2015-2641

Resumo

LNon-isothermal duct flows are among the most important transport phenomena in engineering. In such flows, the viscous frictional head loss parameter is a measure of mechanical energy degradation, but not of the total energy degradation. In non-isothermal flows, both mechanical and thermal energy degradation need be considered. The use of an entropy-based head loss parameter as a measure of energy quality losses in flows with both momentum and conduction-radiation heat transfer is considered in this work. A parametric analysis is also carried out to reveal the role of Reynolds number and Nusselt number in controlling head losses in non-isothermal duct flows. The results show that, under certain flow conditions, selection of a high Reynolds number can significantly reduce the rate of overall head loss. It is also found that Nusselt number is an effective parameter for managing head losses when radiation is a dominant irreversible process.

Palavras-chave: non-isothermal flow; head losses; entropy generation; optimization