Experimental and numerical investigations of shell-side thermo-hydraulic performances for shell-and-tube heat exchanger with trefoil-hole baffles

Orifice plates have been developed as the support of tubes for shell-and-tube heat exchangers, however, very few related academic literature are available. In the present work, we experimentally investigate the shell-side thermo-hydraulic performance of a shell-and-tube heat exchanger with trefoil-hole baffles (THB-STHXs) under turbulent flow regime. The test data demonstrate that the heat transfer rate is effectively enhanced on the shell side, meanwhile, the flow resistance increases substantially. Moreover, both the heat transfer performance ( Nu Pr − 0.333 ( μ f / μ w ) − 0.14 ) and pressure loss (Δp) rise with the increment of the Reynolds number. Based on the experimental results, correlations of the Nusselt number and pressure loss as a function of the Reynolds number are obtained respectively. To analyze the mechanisms of these thermo-hydraulic characteristics, numerical computation is carried out on the basis of a unit channel, which demonstrates that the trefoil-hole baffle could generate high-speed flush, intensive recirculation flow and high turbulence intensity level. As a result, the heat transfer rate is considerably enhanced and the flow resistance increases substantially as well.