http://web.ist.utl.pt/ist11061/leq-II/Documentos/OpUnitarias/BubbleColumnReactors(review).pdf

Bubble column reactors

http://justmechanic.persiangig.com/nirogah./sdarticle5.pdf

The investigation of cooling tower packing in various arrangements

The combination of machine learning and numerical methods has recently become popular in the prediction of macroscopic and microscopic hydrodynamics parameters of bubble column reactors. Such numerical combination can develop a smart multiphase bubble column reactor with the ability of low-cost computational time when considering the big data. However, the accuracy of such models should be improved by optimizing the data parameters. This paper uses an adaptive-network-based fuzzy inference system (ANFIS) to train four big data inputs with a novel integration of computational fluid dynamics (CFD) model of gas. The results show that the increasing number of input variables improves the intelligence of the ANFIS method up to R=0.99, and the number of rules during the learning process has a significant effect on the accuracy of this type of modeling. Furthermore, the proper selection of model’s parameters results in higher accuracy in the prediction of the flow characteristics in the column structure.

https://tandfonline.com/doi/pdf/10.1080/19942060.2019.1613448

Prediction of multi-inputs bubble column reactor using a novel hybrid model of computational fluid dynamics and machine learning

https://lib.dr.iastate.edu/cgi/viewcontent.cgi?article=2653&context=etd

Bed height and material density effects on fluidized bed hydrodynamics

Experimental and theoretical study of a humidification- dehumidification water desalination system using solar energy

The minimum fluidization velocity of beds has been determined experimentally in beds of 0.089 m and 0.29 m diameters, respectively. The particles studied had sizes ranging from 100 μm to 1 mm in diameter, and densities from 1128 to 11400 kg/m3. Three distributors were used in the experimental scheme, each perforated by holes of 0.8 mm in diameter but with varying hole densities, as well as a porous plate. It was found that the minimum fluidization velocity was affected by both the diameter and distributor used. The effect of vertical tubular inserts on the minimum fluidization velocity was investigated in the 0.29 m diameter bed. The experimental data in the large bed, using four distributors, were parameterized within experimental error.

Effect of Bed Diameter, Distributor and Inserts on Minimum Fluidization Velocity

A model for a falling film type cooling tower has been developed to investigate the effect of tower parameters as well as the effect of liquid-side thermal resistance on the tower performance. The energy equation is used to determine the temperature distribution across the liquid film. The heat and mass transfer processes between the liquid film and air bulk are described using three ordinary differential equations. The energy equation was solved using a finite difference Crank-Nicolson scheme. The heat and mass transfer equations were solved using the Runge-Kutta method. The results obtained show that an increase in tower characteristic KaV/L under the same conditions improves the tower performance. The converse is true in the case of increased water to air mass flowrate ratio, L/G. The Lewis number, Le, shows no significant effect on the tower performance. The effect of tower parameters as well as the water inlet temperature on the liquidside Nusselt number and the tower effectiveness was also studied. The results show very insignificant changes in Nusselt number, whereas the effectiveness increases with increasing KaV/L and reduces with L/G, but very insignificant changes occur with Le. The present model is also compared with Merkel's equation. Under the same conditions and with Le equal to unity, the results of the Merkel equation shows a smaller approach than that obtained by the present model.

An investigation into a falling film type cooling tower

Gas holdup in highly viscous fluid in two-phase bubble column with a single sparger operated continuously with respect to the gas flow and batch wise with respect to the liquid was investigated using bed expansion technique. Two- and three-dimensional columns of the same effective cross-sectional area were investigated. Liquid viscosity varied between 0.063 and 0.320 Pa s, static bed heights between 0.12 and 0.60 m, surface tension between 0.0248 and 0.035 N m −1 and density between 906 and 928 kg m −3 . Columns were injected with air at superficial gas velocities between 0.0018 and 0.290 m s −1 . A single nozzle sparger of 0.01 m diameter was used. The behavior of bubbles in two-dimensional bubble column was found to fall into the bubble flow regime, whereas the behavior in three-dimensional column was found to fall into the churn turbulent regime. Two correlations for gas holdup in the two- and three-dimensional bubble columns were proposed and compared with correlations listed in the literature.

Hydrodynamic studies in both bi-dimensional and three-dimensional bubble columns with a single sparger

Analysis of hydrodynamic journal bearings lubricated with a binary water-based lubricant

Extraction of the bitumen fraction of El-Lajjun oil shale was carried out using 17 different solvents, pure and combined. Out of all the solvents used, toluene and chloroform were found to be the most efficient for extraction of the bitumen to perform the major part of the experiments. This selectivity was based on the quality and quantity of the yield and on the quantity of solvent recovered. Extraction was carried out using a Soxhlet extractor. For complete recovery of solvent the extract phase was subjected to two stages of distillation, simple distillation followed by fractional distillation, where different cuts of oil were obtained. It was found that an optimum shale size of 1.0 mm offered better solvent recovery. One hour was the optimum time needed for complete extraction. The yield of oil was determined from the material balance gained from fractional distillation after testing for the existence of any traces of solvent trapped in the different cuts by using a gas chromotography techniqu...

M. Z. Anabtawi

Papers

Effect of Bed Diameter, Distributor and Inserts on Minimum Fluidization Velocity

An investigation into a falling film type cooling tower

Hydrodynamic studies in both bi-dimensional and three-dimensional bubble columns with a single sparger

Analysis of hydrodynamic journal bearings lubricated with a binary water-based lubricant

Extraction of El-Lajjun Oil Shale