关键词: 振荡折流换热器, 螺旋翅片, 强化传热, 计算流体力学

Abstract: Oscillatory baffled heat exchangers （OBHEs） are widely used in chemical processes involving heat or mass transfer. OBHE with spiral fins inserted was simulated using the three dimensional unsteady method in the range of Strouhal number St=2，4，8 and oscillatory Reynolds number Reo=20，40，80. Instantaneous three dimensional stream lines were drawn to show the change of flow status with time，and periodic formation and shedding of spanwise and streamwise vortexes was observed. The changes with time of peripheral local heat transfer coefficients （HTCs）and peripherally averaged HTCs with different oscillatory parameters （St and Reo） were obtained. The local HTCs were not distributed uniformly peripherally and a maximum value was reached at the diagonally across position of fins. Peripherally averaged HTC varied with time periodically and time averaged HTC increased with increasing amplitude，but hardly changed with frequency. In the range covered by this work，averaged HTC could be four times higher than that of tube laminar flow.

Key words: oscillatory baffled heat exchanger, spiral fins, enhancement of heat transfer, CFD