Structural Design Of Double-layer Vibration Fluidized Bed And Analysis Of Temperature Field Characteristics

The traditional vibration fluidized bed dryer has only one layer of upper box distributor.During the drying process.there is only one heat exchange between the hot wind and the material particles.A considerable part of the remaining heat is taken away by the hot wind,so the thermal efficiency is low,especially at high-temperature,the thermal efficiency being even lower.In this paper,a new type of double-layer vibration fluidized bed is designed,and the temperature field is studied by FLUENT numerical simulation.By simulating the temperature inside the vibration fluidized bed body,we can effectively simulate the improvement of drying efficiency of the new double-layer vibration fluidized bed compared to the traditional vibration fluidized bed dryer,and provide a new theoretical basis for the improvement and optimization of its drying process.The overall structure of the double-layer vibration fluidized bed is designed.The basic design standards of the double-layer vibration fluidized bed,that is 1400mm×360mm of bed face,are determined,so as to determine the box structure of the upper and lower beds,including the bed body,the distributor,the incoming and outgoing material device,and the soft connection between the upper and lower beds.The stiffness and excitation force of the supporting spring system are 531.16N/mm and 6615N.The frame structure is finally determined.Then using ANSYS software to do the modal analysis of the bed body of the double-layer vibration fluidized bed.The first ten modes and resonance frequency of the bed body are obtained.The results show that the operating frequency of the double-layer vibration fluidized bed is 64%different from the nearest natural frequency 23.126 Hz.The operating frequency of the vibration fluidized bed can avoid its natural frequency,so the design of the vibration fluidized bed body can meet the requirements of the work.According to the basic working principle of the double-layer vibration fluidized bed structure,the theoretical basis of numerical simulation and mathematical control equation are clarified,and the fluidized parameters of double-layer vibration fluidized bed are calculated.Based on ANSYS FLUENT software for preprocessing.Simplify the geometric model of the entity,divide the grid according to the appropriate method,select the required solution model,define the relative properties of the material,set parameters for the cell and boundary conditions,and select the appropriate solver.FLUENT was used for numerical simulation to simulate the gas-solid two-phase temperature field.The drying effect is described in terms of temperature field.the drying effect is compared by two types of temperature field between the traditional single-layer vibration fluidized bed and the double-layer vibration fluidized bed.The energy consumption analysis shows that the thermal energy utilization rate of the double-layer vibration fluidized bed is 16.4%higher than that of the single layer.