Experimental Study And Numerical Simulation On The Micor-scale Fluidized Beds With Acoustic Intensification

Micro-scale fluidized beds have good characteristics of heat and mass transfer Itssmall size will improve the reaction efficiency, reduce pollution and energy-savingfeatures. The flow characteristics research of tiny particles in a fluidized bed can betterdesign the tiny gas-solid fluidized bed reactor.The fluidization of fine particles fluctuate in the tiny fluidization often havechanneling, slugging phenomenon, leading fluidized ineffective. Usually domestic andinternational through a number of auxiliary measures to solve these problems, such asin a conventional fluidized bed plus magnetic field, vibration field and acoustic field.By introducing the external field can be achieved within the tiny gas-solid fluidizedmass transfer, heat transfer enhancement. The sound field can better and simplyimprove the fluidization quality of the ultrafine solid particles compared otherfluidized bed, based on not changing the internal structure of the conventionalfluidized bed.On the basis of experiments, the fine particle flow characteristics is simulated bycomputational fluid dynamics software fluent6.3in the fluidized bed with acousticassistant. By analyzing the particle bed pressure drop, solid particle distribution andother parameters, provide the basis for small fluidized bed reactor design.Firstly, the fluidization quality of fine particles was researched by experimentaland simulation in the Micro-scale fluidized beds of changes in distribution. Recordedand analyzed the graphs of gas velocity-pressure drop, and compared with simulatedvalues, the air distribution chamber has been changed to improve the flow of both thequality of the tiny particles in the fluidized bed. Through analyzing the contours ofsolid volume fraction, verified the optimization of device is right.Secondly, the fluidization characteristics of Class A and Class C particle was researched in micro-scale fluidized bed with the sound field. The sound field numericalmodel was establish. Analyzed the affect of granular flow quality with acoustic, bycomparing the numerical simulation of the contours of solid volume fraction. Acquiredthe completion of sound field can improve the quality of the stream of tiny particles ina fluidized bed. Combined with the value of pressure fluctuations to verify the effect ofparticle flow improved.Thirdly, the heat transfer performance with acoustic assist in micro-scale fluidizedbed was researched. Fluidized bed heat transfer through the establishment of a soundfield numerical model to simulate the bed temperature distribution. Value of eachsection of the formula to calculate the temperature and the resulting simulated by bedheat transfer coefficient between the calculated heat transfer coefficient. Bycomparing the value of heat transfer coefficient, the influence of the sound pressurelevel about the fluidized bed heat transfer performance was analyzed, while theeffects of the heat transfer coefficient in different height of fluidized bed isresearching.