Biogas is one of the most crucial renewable energy and achieving high-efficient heat exchangers is the key to improve its production. In this study, the effect of pulsating flow on heat transfer in a twisted hexagonal tube with manure slurry was investigated for the first time by using computational fluid dynamics CFD. The performances of pulsating flows were simulated under different conditions, including the inlet velocity, frequency, and amplitude of pulsating flow in the twisted hexagonal tube with different torques. Pressure drops at different frequencies were further investigated. Moreover, the mechanism of heat-transfer enhancement was revealed with the evolution of the heat-transfer coefficient over time. It was found the pulsating flow achieves an 18.9% enhancement at low torque.
Keywords heat-transfer enhancement, pulsating flow, twisted hexagonal tube, CFD, manure slurry