K.C. Biswal

Prediction of minimum fluidization velocity for gas-solid fluidization of regular particles in conical vessels

Abstract The application of a conical fluidized bed as a remedial measure for certain inherent drawbacks of gas-solid systems is suggested. Investigations were carried out in Perspex cones with apex angles of 10°, 30°, 45° and 60°, with spherical glass beads of different sizes as the bed material, and air as the fluidizing medium. With the help of available correlations and packed bed pressure drop data, minimum fluidization velocities for the above cases were computed and compared with experimental data obtained from bed pressure drop versus fluid mass velocity plots, and the mean and standard deviations were calculated.

Prediction of Pressure Drop for a Conical Fixed Bed of Spherical Particles in Gas-Solid Systems

The object of this work was to develop an equation to predict the pressure drop in conical beds of spherical particles. Work reported earlier is limited to a single cone angle in liquid—solid systems, whereas in the present study cone angles of 10°, 30°, 45° and 60° were used to predict the pressure drop for fixed beds. Air was used as the fluid medium and the bed consisted of spherical glass particles of various sizes. The constants C1 and C2 were determined and were used to calculate pressure drop values. Experimental and theoretical values of pressure drop were compared and the mean and the standard deviation were calculated.

Prediction of the Fluctuation Ratio for Gas Solid Fluidization of Regular Particles in a Conical Vessel

Copyright for this article belongs to Elsevier Science Ltd http://dx.doi.org/10.1016/0300-9467(82)85011-9

Quantification of Seismic Response of Partially Filled Rectangular Liquid Tank with Submerged Block

The seismic behavior of partially filled rigid rectangular tank with bottom-mounted submerged block is numerically simulated. Six different ground motions characterized on the basis of low-, intermediate-, and high-frequency contents are used to investigate the dynamic behavior of tank-liquid-submerged block system. A velocity potential-based Galerkin finite element model is developed for the analysis. The effect of submerged block on impulsive and convective response components of hydrodynamic behavior manifested in terms of base shear, overturning base moment, and pressure distribution along the tank wall as well as the block wall has been quantified.

A numerical study of violent sloshing problems with modified MPS method

A numerical study on violent liquid sloshing phenomenon in a partially filled rectangular container is carried out by using moving particle semi-implicit (MPS) method. The present study deals with the implementation of five modifications all together over the original MPS method. The modifications include improved source terms for pressure Poisson equation, special approximation technique for the representation of gradient differential operator, collective action of mixed free surface particle identification boundary conditions, effecting Neumann boundary condition on solving the PPE and fixing judiciously the parting distance among particles to prevent collision. The suitability of the kernel function used in the original MPS method along with these five modifications is investigated for violent sloshing problems. The present model ensures a good agreement between numerical results with the existing experimental observations. The model is successfully applied to a partially filled tank undergoing horizontal sinusoidal excitation to compute the sloshing wave amplitudes and pressure on tank walls. The assessment of dynamic behaviour manifested in terms of base shear, overturning moment and impact pressure load exerted on tank ceiling induced by violent sloshing motion using MPS method is not reported in the open literature and has been efficiently carried out in the present study.

Violent Sloshing and Wave Impact in a Seismically Excited Liquid-Filled Tank: Meshfree Particle Approach

AbstractA meshfree particle approach, namely moving particle semi-implicit (MPS) method is used to investigate the sloshing behavior in a partially filled liquid container. The validity of the nume...

Bed Fluctuation Ratio for Regular and Irregular Particles in Gas-Solid Tapered Fluidised Beds

Abstract The fluctuation ratios for regular and irregular particles have been investigated in gas-solid tapered fluidised beds. Based on dimensional analysis, models have been developed with the system parameters viz. geometry of tapered bed, particle diameter, static bed height, density of solid and gas, and superficial velocity of the fluidising medium. Effects of static bed height, particle diameter and tapered angle on fluctuation ratio have been investigated. A comparison has been made between the estimated values of bed fluctuation ratios using the proposed models, experimental values and the model available in literature for conical beds. It has been found that the average absolute errors between the experimental measured values and the predicted values from the proposed models are within ±15%.