Natural convection heat transfer performance of additively manufactured tube bundle heat exchangers with novel fin design

Abstract We studied the heat transfer of finned exchanger configurations with a novel design. These fin designs use integrated pins to enhance conduction from base tip as well air-side on surface. Oval tubes conventional circular plain fins (CPF) pin (CIPF) and serrated (SIPF) were additively generated by Selective Laser Melting (SLM) process installed at bottom 6.5 m long chimney. All tested in 2-row 3-row configuration Rayleigh numbers between 25,000 120,000. found average Nusselt number SIPF be higher CIPF lower than for CPF. Moreover, achieved compared all designs. The analysis individual tube rows showed highest first row lowest one last both configurations. However, difference second is smaller CPF CIPF. In order evaluate compactness exchanger, volumetric flux density was considered. Similar enhanced reduced Also reached greater thermal performance configuration. Additionally, volume surface area are 6.9% 30.7% experimental data used develop an empirical correlation number, design number.