Analysis on flow and heat transfer characteristics of EGR helical baffled cooler with spiral corrugated tubes

The flow and heat transfer characteristics in shell and tube exhaust gas recirculation (EGR) helical baffled cooler with spirally corrugated tubes (HBCSCTs) were studied by experiment and numerical simulation. An experimental set-up was designed to study the effects of the tube and baffle shapes on heat transfer and pressure drop in both tube side and shell side. The maximum deviations between the present numerical results and the experimental data are approximately 7.8% for pressure drop, 7.4% for friction factor and 6.1% for Nusselt number. Compared numerically with EGR segmental baffle cooler with smooth tubes (SBCSTs), the results indicated that the tube-side Nusselt number of EGR-HBCSCT is improved by 60-130%, while the shell side resistance decreases 8.2-9.5%. The total heat transfer coefficient of the novel EGR cooler is 1.6-2.2 times higher than EGR-SBCST. The EGR-HBCSCT shows better performance.