We present the results of a combined experimental and theoretical investigation of sedimentation in a stratified fluid. The theory of sedimentation in a homogeneous ambient is extended to include the influence of a spatially varying particle settling speed. The results of an experimental investigation of latex particles settling in a stably stratified salt water solution are reported. Density v...

a mathematical method for calculation of the minimum cross-sectional area of a thickener is presented by obtaining minimum laboratory batch settling test data, a function, which is called settling function, is derived. this function is found to be in the form of a polynomial of third order. the settling function and mass flux relation are used for the design of thickener. the method predicts th...

coarse product in the underflow. It is well known that injecting water in the conical part of the cyclone reduces the fine particle fraction in the underflow. This paper presents a mathematical model that simulates the water injection in the conical component. The model accounts for the fluid flow and the particle motion. Particle interaction, due to hindered settling caused by increased densit...

Direct numerical simulations of homogeneous isotropic turbulence are used to investigate the effects of turbulence on the transport of particles in gas flows or bubbles in liquid flows. The inertia associated with the bubbles or the particles leads to locally strong concentrations of these in regions of instantaneously strong vorticity for bubbles or strain-rate for particles. This alters the a...

An Euler-type gas/particle two-phase flow numerical model is presented for simulating the deposition of particles of tens of microns. At this size range of particles, the dominant effect considered for deposition on the bottom surface is gravitational settling. The mass conservation equation for the particulate phase is developed and simulated to include convection, diffusion, and gravitational...

Dust grain growth and settling time inside initial gaseous giant protoplanets in the mass range 0.3 to 5 Jovian masses, formed by gravitational instability, have been investigated. We have determined the distribution of thermodynamic and physical variables inside the protoplanets solving the structure equations assuming their gas blobs to be fully convective and with this distribution we have c...

In this contribution, a new approach for teaching digital controllers for finite settling time and deadbeat response is proposed. Essential concepts of deadbeat control are revised and shorted in order to simplify the teaching. The approach is base on a constructivist instructional model, which is supported by wellknown pedagogical tools as the learning cycle, the sandwich structure and the por...

The study was carried out to identify and study the settling characteristics of the dairy activated sludge. The causes and the control measure for the sludge bulking were studied. The activated sludge was generated by running a batch reactor of capacity of 10 liters for a θC of 10 days. It was operated until steady state conditions were reached. pH, DO, MLSS and COD were taken as the parameters...

New data on the settling velocity of artificial sediments and natural sands at high concentrations are presented. The data are compared with a widely used semiempirical Richardson and Zaki equation (Trans. Inst. Chem. Eng. 32 (1954) 35), which gives an accurate measure of the reduction in velocity as a function of concentration and an experimentally determined empirical power n. Here, a simple ...