Theoretical And Experimental Research On A New Type Of Fluidized Bed Heat Exchanger

The study shows that the fluidized bed heat exchanger has a lot of advantages, suchas high heat transfer performance, difficult to scale, easy to maintenance, etc. Moreenergy will be saved as the fluidized bed heat exchanger is used in industrial production.In response to this situation and according to domestic and international research statusof the fluidized bed heat exchanger, the research program of a new type of fluidized bedheat exchanger is proposed. With this new type of fluidized bed heat exchanger, notonly the heat transfer of general industry production is satisfied, but also the industriallow-temperature waste heat can be effectively recycled. The key basic theory of thisresearch program is the heat transfer between the gas-solid flow and tubes in thefluidized state. This paper carries out theoretical simulation and experimental studies.The following key issues are solved:(1) Based on the domestic and international study, a new type of fluidized bed heatexchanger unit is proposed for the first time. The waste heat of industriallow-temperature flue gas can be recycled by this device, so that the waste of resourcescan be reduced. High economic benefits will be obtained.(2) According to the design requirements for the fluidized bed heat exchanger, theoverall design is done to the fluidized bed heat exchanger device, including the furnace,heat exchanger tube, air pipes, water system, cyclone separating device and accessoryequipment.(3) According to the physical nature of the two-phase flow in the fluidized bedheat exchanger, the gas-solid two-phase flow mathematical model of the air andparticles is established. The interaction between the air and particles is analyzed underthe fluidized state. And the heat transfer model of the dense air-particles two-phase flowis established. According to the structure of the heat exchanger, a part is taken asresearch space and the geometric model is created. Fluidized heat transfer is simulatedby computational fluid dynamics software in order to ascertain the influence from someparameters to the heat transfer performance.(4) Based on the simulation results, further experimental research is carried out inthe fluidized bed heat exchanger test bed. Taking air velocity and particle diameter asvariables respectively, pressure and temperature is measured under various operatingconditions. Comparing the simulation results and the experimental results, the heattransfer characteristics of the fluidized bed heat exchanger device can be verified.