In this research, a cold model of internally circulating fluidized bed is investigated. The aim is to find the effects of some of the operating parameters on the performance of the reactor. Experiments were carried out in a glass column (30 mm i.d. and 25 cm height) with a centrally located draft tube (11 mm i.d. and 5 or 7 cm height). The bed was loaded with white silica particles (dp = 0.15 -...

The extinction of an envelope flame at the forward stagnation point of a liquid fuel droplet due to forced convection is numerically investigated. The droplet is oxidizing within an air stream at atmospheric pressure. Combustion is modeled using finite-rate chemical kinetics and a one-step overall reaction. The gas-phase solution is obtained using the quasi-steady equations of mass, momentum, s...

The ALICE TPC is a detector with a total volume of 88 m filled with a ternary gas mixture of Ne-CO2-N2 [9010-5]. To achieve its position and energy resolution requirements it is necessary to control small fluctuations in the gas composition as well as drift velocity variations [1]. A modified drift velocity monitor known as Goofie is measuring the drift velocity and also the gain. The drift vel...

We present new FUSE spectroscopy of the dwarf starburst galaxy NGC625. These observations probe multiple phases of the interstellar medium, including the coronal, ionized, neutral and molecular gas. This nearby (D = 3.9± 0.2 Mpc) system shows a clear detection of outflowing coronal gas as traced by O VI λ 1032 Å absorption. The centroid of the O VI profile is blueshifted with respect to the gal...

effect of temperature on hydrodynamics of bubbling gas-solid fluidized beds was investigated.  experiments were carried out in the range of 25-600 ºc and different superficial gas velocities in the range of 0.17-0.78 m/s with sand particles. time-position trajectory of particles was obtained by radioactive particle tracking technique. these data were used for determination of mean velocities of...

A theoretical model is developed for electron velocity saturation in high power GaN transistors. It is shown that electron velocity at high electric fields is reduced due to heating of electron gas since the high density of nonequilibrium LO phonons cannot efficiently transfer heat to the lattice. However, the resulting degradation of electron velocity is found to be weaker than previously repo...

A numerical simulation was performed on a turbulent gas-particle multi-phase flow in a circulating fluidized bed riser based on a hard-sphere discrete particle model (DPM) for the particle phase and the Navier-Stokes equations for the gas phase. The sub-grid scale stresses (SGS) were modeled with the SGS model proposed by Vreman (2004). The model enables the calculation of an arbitrary particle...

We report on a detailed morphological and kinematic study of the isolated non-barred nearby Seyfert 2 galaxy NGC 2110. We combine Integral Field optical spectroscopy, with long-slit and WFPC2 imaging available in the HST archive to investigate the fueling mechanism in this galaxy. Previous work (Wilson & Baldwin 1985) concluded that the kinematic center of the galaxy is displaced ∼ 220 pc from ...

High frequency oscillatory ventilation takes advantage of unique principles of gas flow when respiratory frequencies exceed 3 Hz (180 breaths per minute). These gas flow principles enable the alveolar gas turnover at volumes below or equal to physiologic deadspace. One of these principles is call asymmetrical velocity profile. As Froese and Bryan described in their “State of the Art” article on...