Computational Analysis for Good Thermal Exchange and Low Pressure Drop in Regenerative Air Preheaters
P. C. Mioralli *
Federal Institute of São Paulo – IFSP, Campus Catanduva, Brazil.
M. A. B. Da Silva
Federal Institute of São Paulo – IFSP, Campus Catanduva, Brazil.
E. Avallone
Federal Institute of São Paulo – IFSP, Campus Catanduva, Brazil.
P. H. Palota
Federal Institute of São Paulo – IFSP, Campus Catanduva, Brazil.
P. S. G. Natividade
Federal Institute of São Paulo – IFSP, Campus Catanduva, Brazil.
*Author to whom correspondence should be addressed.
Abstract
A computational analysis in a rotary regenerative air preheater subject to pre-established mass flow rate is performed. The heat transfer rate, the pressure drop and the outlet temperatures of gas streams are calculated from different matrix porosity values. The fluid flow and the convective heat transfer coefficient are determined from correlations. The total heat transfer is obtained using the Effectiveness-NTU method specific to regenerative air preheaters. Three typical regenerative air preheaters with both streams under the laminar flow regime are investigated. A range of porosity values that provide good thermal exchange and low pressure drop in the equipment is chosen for each examined air preheater. The behavior of the outlet temperatures of each gas stream as function of porosity is also analyzed. The results show that the porosity ranges shorten when the typical pressured drop values for each regenerative air preheater are introduced in the analysis. In addition, the behavior of the outlet temperatures is compatible with the behavior of the heat transfer rate as the porosity changes.
Keywords: Regenerative air preheater, heat transfer, pressure drop, simulation