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gas-centrifuges
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Experimental investigation of effects of the feed flow rate and “tail scoop-wall” clearance on the performance of a gas centrifuge by feeding a Freon mixture
, Article Separation Science and Technology (Philadelphia) ; Volume 51, Issue 7 , 2016 , Pages 1259-1267 ; 01496395 (ISSN) ; Outokesh, M ; Karimi Sabet, J ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
ABSTRACT: Experimental study of the performance of a gas centrifuge can be appreciably simplified if instead of isotopic mixtures, a binary mixture of gases with large molecular weight difference is used. The current study undertook this approach by injecting a 53%–47% (w/w) mixture of “Freon12-Freon22” into a gas centrifuge. The two parameters, whose investigation was the objective of the current study were: the feed flow rate (F), and the clearance between tail scoop and the rotor wall (d). The results demonstrated that changing the scoop-wall clearance has the most significant effect on the cut (θ), so that by fixing “d”, “θ” becomes nearly invariant. The head separation factor (α)...
Optimization of Enriching Cascades Using Genetic Algorithms
, M.Sc. Thesis Sharif University of Technology ; Otukesh, Mohammad (Supervisor) ; Norouzi, Ali (Supervisor) ; Ayoubzadeh, Mohsen (Co-Advisor)
Abstract
One of the challenging issues in Iran's nuclear talks and Group 5+1 countries is the amount of Iran's enrichment capacity and the number of centrifuges needed to meet this demand. In this regard, Iran has recently announced that the basis for determining its enrichment capacity is the supply of fuel for the Bushehr power plant.Modeling and optimizing of gas centrifuge cascade is one of the most important problems in fuel cycle and isotope separation fields. To achieve this goal it is needed to comprehend of single centrifuge operation. Knowing the effectofsingle centrifuge parameters, it is easy to design a desired cascade. Minimizing the number of machines in the cascade is an anticipated...
Study on the Mass Transfer and Isotope Separation Phenomena in a Gas Centrifuge by Using FEREON Mixtures as Model Compounds
, M.Sc. Thesis Sharif University of Technology ; Outokesh, Mohammad (Supervisor) ; Karimi-Sabet, Javad (Supervisor) ; Norouzi, Ali (Co-Advisor)
Abstract
In the nuclear industry, gas centrifuges are considered of high importance for the purpose of uranium enrichment. Today, with advances in science and technology, the use of gas centrifuges for separating isotopes other than uranium, is so common. With respect to the use of conventional methods such as Pancake equation in calculating the velocity profile in centrifuges, it is needed that A^2=(MV^2)/2RT≫1 (M: Feed molecular weight; V: Peripheral speed of centrifuge; T: Mean temperature of feed; R: The universal constant of gases). While the molecular weight of the feed mixture gets lower, the A2 parameter gets closer to one. So, other methods for modeling the behavior of the gas in the...
Investigation of the continuum-rarefied flow and isotope separation using a hybrid CFD-DSMC simulation for UF6 in a gas centrifuge
, Article Annals of Nuclear Energy ; 2020 ; Akbar Salehi, A ; Reza Keshtkar, A ; Mahdi Shadman, M ; Hossein Askari, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
UF6 gas flow in the total regions of a rotor with the radius of 0.1 m and the length of 1 m in axisymmetric and steady states was simulated using a new hybrid CFD-DSMC method in the OpenFOAM framework. Implicit coupled density-based scheme was performed for CFD method, and Variable Hard Sphere (VHS) and diffuse model were employed in DSMC method. Also, as an initial estimation, the local Knudsen number was applied to determine the interface location between the continuum-rarefied regions (r = 0.0855 m). Then it was modified (r = 0.084 m) to reduce the computational cost. The comparison results of pure CFD and CFD-DSMC methods illustrated that there were large differences between the flow...
Modeling and simulation of flow and uranium isotopes separation in gas centrifuges using implicit coupled density-based solver in OpenFOAM
, Article European Journal of Computational Mechanics ; Volume 29, Issue 1 , 2020 , Pages 1-26 ; Salehi, A. A ; Keshtkar, A. R ; Shadman, M. M ; Askari, M. H ; Sharif University of Technology
River Publishers
2020
Abstract
The performance of a gas centrifuge that is used for isotopes separation is dependent on the gas flow inside it. In this study, for modeling the UF6 gas flow, an Implicit Coupled Density-Based (ICDB) solver, was developed in OpenFOAM. To validate the ICDB solver, the gas flow within the rotor in total reflux state was compared with the analytical solution obtained by Onsager model and the numerical solution obtained by the Fluent software. The results showed that the ICDB solver had acceptable accuracy and validity. Also the computational efficiency of Roe, AUSM (Advection Upstream Splitting Method) and AUSM+ up schemes were compared. The results showed AUSM+ up scheme is efficient. Then,...