Search for: large-diameter
Investigation on the Effect of air Inlet on the Behavior of Air-Water two Phase Flow in a Large Diameter Vertical Tube, M.Sc. Thesis Sharif University of Technology ; Saidi, Hassan
Knowledge of Air-water two phase flows is significant to different engineering systems such as chemical reactors and power plant and petrochemical and petroleum industry. One of the most industrial cases of two phase flow is two phase flow in vertical large pipes. Because of gravity, two phase flow in Vertical pipes is different from horizontal pipes. Considering these flows can play a significant role in long-term reliability and safety of industrial systems. There are many parameters that effect on flow characteristics such as length and diameter of pipe and shape and condition of air inlet. Effect of air inlet is on the shape of bubbles and this can effects on flow pattern and another...
Article Particuology ; Volume 39 , 2018 , Pages 96-108 ; 16742001 (ISSN) ; Behjat, Y ; Safekordi, A. A ; Sharif University of Technology
Elsevier B.V 2018
To investigate the gas–solid flow pattern of a combustor-style fluid catalytic cracking regenerator, a laboratory-scale regenerator was designed. In scaling down from an actual regenerator, large-diameter hydrodynamic effects were taken into consideration. These considerations are the novelties of the present study. Applying the Eulerian–Eulerian approach, a three-dimensional computational fluid dynamics (CFD) model of the regenerator was developed. Using this model, various aspects of the hydrodynamic behavior that are potentially effective in catalyst regeneration were investigated. The CFD simulation results show that at various sections the gas–solid flow patterns exhibit different...
Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010 ; Volume 7, Issue PARTS A AND B , November , 2010 , Pages 1735-1741 ; 9780791844441 (ISBN) ; Karrabi, H ; Rezasoltani, M ; Saidi, M. H ; Sharif University of Technology
Knowledge of Air-water two phase flows is significant to different engineering systems such as chemical reactors and power plant and petrochemical and petroleum industry. One of the most industrial cases of two phase flow is two phase flow in vertical large pipes. In this paper in order to find two phase flow behavior along vertical large diameter pipes we simulate air inlets with different number of holes and different hole diameters in the same flow rate of air. In addition, flow characteristics such as cross-sectional void fraction and velocity and pressure were considered. To achieve this aim, main equations of flow have been developed for investigation of flow behavior in air-water two...
Article Journal of Mechanical Science and Technology ; Volume 26, Issue 11 , 2012 , Pages 3389-3397 ; 1738494X (ISSN) ; Firouz Abadi, R. D ; Haddadpour, H ; Noorian, M. A ; Sharif University of Technology
The instability of large diameter single-walled carbon nanotubes (SWCNTs) conveying fluid is investigated based on the molecular mechanics. Using the modal expansion for structural displacements, the governing equations of coupled fluid-structural dynamics of SWCNTs are derived. The natural frequencies and mode shape of the SWCNTs are obtained based on the molecular structural mechanics to account for the effect of chirality and discrete nature of SWCNTs. The results show that the vibrational behavior of large diameter SWCNTs conveying fluid is size dependent, but the effect of chirality is negligible. The obtained results are compared with the equivalent continuum-based model in the...
Article Materials Science and Engineering A ; Volume 539 , 2012 , Pages 285-293 ; 09215093 (ISSN) ; Ashrafi, M. J ; Arghavani, J ; Sharif University of Technology
Employing a proper pulse shaper in the conventional split Hopkinson pressure bar (SHPB) test helps to achieve dynamic equilibrium condition and to fulfill a constant strain rate condition in the test specimen. To this end, the parameters affecting the incident pulse shape, i.e., pulse shaper thickness, pulse shaper diameter, striker bar length and striker bar velocity are experimentally studied. Moreover, simulation results, validated by experimental data together with wave propagation analysis, are exploited to provide general guidelines to properly design a pulse shaper. It is recommended to use a relatively large diameter pulse shaper for testing work-hardening materials. Also, for...