Measurement of the heat transfer coefficient in plate heat exchangers using a temperature oscillation technique

Abstract

Thermal parameters of plate type heat exchangers are experimentally evaluated using a temperature oscillation technique. A mathematical model with axial dispersion has been utilised to evaluate heat transfer coefficient and dispersion coefficients characterised by NTU and Péclet number, respectively. Special reference has been made to the deviation from plug flow due to the phase lag effect in a U-type plate heat exchanger. A mathematical model for correcting the thermal penetration effect in plate edgings and thick end plates has been presented. The experimental results obtained by using the temperature oscillation technique have been compared with those obtained by traditional steady-state experiment. A series of developments have been suggested to make the method more suitable for plate type heat exchangers.