Thermal and hydraulic performance of pillow-plate heat exchangers

Pillow-Plate Heat Exchangers (PPHEs) represent an innovative equipment type, with space-effective, light and pressure-resistant construction. In this work, an experimental study of air cooling by water in small-scale pillow plates was carried out and an analysis of the hydraulic resistance and heat transfer inside the PPHEs was performed based on the experimental data. The correlations for friction factor and heat transfer in PPHEs channels were proposed and validated by the measurements of small-scale PPHEs. The correlation for the heat transfer coefficients in the channel with hot heat carrier is based on the modified Reynolds analogy between heat and momentum transfer; it is valid for fully developed turbulent flow with the Reynolds numbers between 2,000 and 20,000. The deviation of the data predicted by the proposed correlations from the experimental results is within +/- 10 %. The experimental data processing was realised using the developed software. The proposed correlations can be applied for the mathematical modelling of PPHE design parameters.