Evaluation of plate heat exchangers comprising sections with different chevron angle arrangements

Gasketed Plate Heat Exchangers (GPHEs) are essential equipment for thermal control of oil facilities owing to their compactness and well-organized assembly concept. In order to satisfy heat loads of several megawatts, numerous and large plates are necessary. The application of GPHEs with plentiful plates yields flow maldistribution which affects GPHE thermal-hydraulic performance. With the purpose of matching different heat loads and processing conditions or as an alternative to reduce maldistribution effects, GPHEs with mixed arrangements, comprising sections where channels contain different geometrical features, may be selected. This works addresses the evaluation of flow and pressure distributions in GPHEs with mixed arrangements. The pressure drop in each GPHE section is initially approximated by the pressure drop in parallel pipes, neglecting the pressure drop in the ports. With this assumption, the inlet flow rate is divided into two different parts. The pressure distributions in each section are assumed to maintain flow features of m2 2-model for U-type arrangement. The friction factor for each GPHE segment was determined with independent experiments including only one section type and with a small number of channels as to avoid flow maldistribution. Friction factor correlations were determined for single section GPHEs where each channel can be formed with plates containing different chevron angles: 30 degrees/30 degrees, degrees /30 degrees , 60 degrees/60 degrees, degrees /60 degrees , 66 degrees/66 degrees, degrees /66 degrees , 30 degrees/60 degrees degrees /60 degrees and 30 degrees/66 degrees, degrees /66 degrees , with channel Reynolds number ranging from 260 to 3,080. Subsequently, experiments with GPHEs containing mixed sections with high and low pressure drop channels were performed: 60 degrees/60 degrees degrees /60 degrees and 30 degrees/30 degrees, degrees /30 degrees , 30 degrees/30 degrees degrees /30 degrees and 66 degrees/66 degrees; degrees /66 degrees ; with total number of channels up to 180. The channel pressure drop was measured in regularly spaced locations. The pressure drop in each GPHE segment has been predicted with the fractional RMS deviation equal to 2.2%. Although the mass flow rate per channel has not been measured, it is expected that the predicted flow rate distribution can reasonably stand for the real one and, therefore, assisting in proper thermal performance evaluation.