Heat transfer improvement in a double pipe heat exchanger by means of perforated turbulators

Forced convective turbulent hydrothermal analysis in a double pipe heat exchanger is presented experimentally. Perforated turbulators have been utilized in annulus region. Hot water makes the cold air in outer tube warmer. Various amounts of pitch ratio, open area ratio and Reynolds number are considered. Correlations for Nusselt number, thermal performance and Darcy friction factor are examined. NSGA II is utilized to optimize the design. Physical phenomena are shown by means of FVM. Results reveal that thermal performance enhances with augment of open area ratio. Temperature gradient reduces with augment of pitch ratio. The maximum value of thermal performance obtained at eta = 1.59 which is occurred for Re = 6000, lambda = 0.07, PR = 1.06. (C) 2016 Elsevier Ltd. All rights reserved.