Chemical Engineering Commons^™

Hydrodynamic Characteristics Of A Fluidized Bed With Rotating Distributor, C. Sobrino, S. Sánchez-Delgado, J. A. Almendros-Ibáñez, M. De Vega, U. Ruiz-Rivas, D. Santana

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

The performance of a novel rotating distributor fluidized bed is presented. The pressure drop and the standard deviation of pressure fluctuations, σp, were used to find the minimum fluidization velocity, Umf, and to characterize the quality of fluidization at different rotational speeds of the distributor plate. Experiments were conducted in the freely bubbling regime in a 0.19 m i.d. fluidized bed, operating with Group B particles according to Geldart’s classification. A decrease in Umf is observed when the rotational speed increases. Frequency analysis of pressure fluctuations shows that fluidization can be controlled by the adjustable rotational speed, at several excess …

Prediction Of The Dynamics Of A Fluidized Bed Reactor Using Artificial Neural Networks, Shayan Karimipour, Navid Mostoufi, Rahmat Sotudeh -Gharebagh

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

The dynamic behavior of fluidized bed has been studied based on the chaos theory. The experiments were done in a fluidized bed of 0.15 m diameter using an optical fiber probe. The interval between successive clusters in the fluidized bed were calculated from the time series signals and proved to be chaotic by calculating the correlation dimension. An artificial neural network (ANN) was adapted and trained to predict the generated time series. The ANN results were compared with the predictions of the k-Nearest Neighbor (kNN) method to show the superiority of ANN in chaotic time series prediction.

Experimental Analysis Of Fuel Mixing Patterns In A Fluidized Bed, David Pallarès, Pedro A. Díez, Filip Johnsson

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

The mixing pattern of a tracer particle which simulates a fuel particle is studied in a cold 2-dimensional fluidized bed with respect to the influence of fluidization velocity, bed height, tracer particle size and air-distributor pressure drop under conditions typical for bubbling fluidized bed boilers as well as the bottom region of circulating fluidized bed boilers. The results show that for all conditions studied, the tracer particle follows a flow pattern structured into horizontally-aligned vortexes.

The Measurement Of Thermal Performance For A Fluidized Bed, H. R. Goshayshi

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

Abstract Experiments have been performed to measure the thermal performance, packed density, and velocity of a fluidized bed cooling tower of 280 mm diameter.

Hollow plastic spheres of three different sizes, with diameters of 20, 25 and 37 mm and particle densities ranging from 70 to 325 kg/m3 were investigated as packing materials, and results for static bed heights of 100 mm and 300 mm are reported. Measurements were obtained at an approximately constant inlet hot water temperature of around 42°C and cover a range of water mass flux from 0.3 to 3.6 kg/sm2. Liquid/gas ratios varied between 0.1 and …

Scale-Up Effect On Heat Transfer In A Fluidized Bed Near The Onset Of Turbulent Fluidization, A. Stefanova, John R. Grace, C. Jim Lim, Xiaotao T. Bi, K.S. Lim, J. Sanderson

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

Heat transfer coefficients were measured in 0.29 m ID and 1.56 m ID fluidization columns with the same heater tube, identical alumina particles and geometrically scaled distributors. The maximum coefficients occurred in the turbulent fluidization flow regime. The Froude number based on superficial velocity and column diameter captures the scale-up effect well, so long as the heater is located in a region of similar flow structure.

Gas-Solid Structure In The Vicinity Of A Sparger Nozzle In A Fluidized Bed, Pierre Sauriol, Heping Cui, Jamal Chaouki

The 12th International Conference on Fluidization - New Horizons in Fluidization Engineering

An experimental approach is proposed to investigate the gas-solid structure in the vicinity of a sparger nozzle in a fluidized bed. The local hydrodynamics were studied under injection velocities ranging between 0 and 100 m/s and three orientations. A fiber-optic probe was used to measure the instantaneous local particle holdup near the tip of the sparger nozzle. Under the investigated conditions, the local gas-solid structure was influenced on the measurement position, nozzle orientation and injection velocity. Four distinct zones were identified from the local particle holdup data, with the boundaries corresponding to characteristic jet lengths. Strong discrepancies were found with …