Abstract:
To improve the flow and heat transfer performance of fluoroplastics heat exchanger, the thermal resistance ratio of the fluoroplastics heat exchanger was analyzed. The flow and heat transfer model of fin-tube heat exchanger was established, and the effects of fin parameters, tube spacing parameters and fluoroplastics species on the flow and heat transfer performance of heat exchanger were simulated. The results show that the average thermal resistance ratios in air side and tube wall are up to 60.0% and 30.0%, respectively. Nusselt number(Nu)and pressure drop keep almost constant with the increasing of fin thickness. With the increasing of fin spacing and tube longitudinal spacing, Nu number is increased, and pressure drop is decreased. With the increasing of tube transverse spacing, Nu number is decreased, and pressure drop is increased. When fin spacing, thickness, tube transverse and longitudinal spacing are respective 9, 1.2, 10 and 20 mm, the optimal comprehensive performance of fluoroplastics heat exchanger can be obtained. Compared with heat exchanger with smooth fluoroplastics tube, the total heat transfer coefficients of the common fin-tube fluoroplastics heat exchanger and the fin-tube graphene flurorplastics heat exchanger are increased by 2.5%-21.0% and 16.0%-55.0%, respectively.