Determination of External Convection Coefficient in Double Tube Heat Exchanger Thyrson Niênio Rodrigues Sousa, Marcelo Yamaguti, Luis Felipe Collacio Messias, Pedro Pereira Torga, Pedro Wanderley Ventura, Rodrigo Rolim Coutinho e Silva, Murilo Antunes Alves Lucindo, Vitor da Silva Rosa

Abstract

 Heat exchangers are equipment responsible for transferring heat between fluids. The aim of this study was to empirically determine the external convection coefficient of a double-pipe heat exchanger with baffles. The tests were conducted with cold fluid flow rates varying between 5 and 30 LPM, while the hot fluid flow rate was kept constant. The results showed that the presence of the baffles significantly increased the external convection coefficient ( h_o ), ranging from 757 W/m²°C to 1968 W/m²°C, compared to the expected value of 483 W/m²°C without baffles. Additionally, a decrease in LMTD was observed with the increase in the cold fluid flow rate. It is concluded that baffles in double-pipe heat exchangers are effective in improving thermal efficiency.