CPS construction for laser coating with a general-purpose three-dimensional thermohydraulics numerical simulation code SPLICE

The paper presents a three-dimensional (3-D), time-dependent Euler-Lagrange multiphase approach for high-fidelity numerical simulation of strongly swirling, turbulent, heavy dust-laden flows within large-sized cyclone separators, as components of the state-of-art suspension preheaters (SPH) of cement kilns. The case study evaluates the predictive performance of the coupled hybrid 3-D computational fluid dynamics–dense discrete phase model (CFD-DDPM) approach implemented into the commercial general purpose code ANSYS-Fluent R16.2, when applied to industrial cyclone collectors used to separate particles from gaseous streams. The gas (flue gases) flow is addressed numerically by using the traditional CFD methods to solve finite volume unsteady Reynolds-averaged Navier-Stokes (FV-URANS) equations. The multiphase turbulence is modeled by using an option of Reynolds stress model (RSM), namely dispersed turbulence model. The motion of the discrete (granular) phase is captured by DDPM methodology. The twin cyclones of SPH top-most stage have been analyzed extensively both for the overall pressure drop and global collection efficiency, and for the very complex multiphase flow patterns established inside this equipment. The numerical simulation results have been verified and partially validated against an available set of typical industrial measurements collected during a heat and mass balance (H&MB) of the cement kiln.

Download Full-text

Numerical Simulation of Thermal Striping Phenomena in T-Junction Piping System Using Large Eddy Simulation

Volume 2: Fuel Cycle and High Level Waste Management; Computational Fluid Dynamics, Neutronics Methods and Coupled Codes; Student Paper Competition ◽

10.1115/icone16-48667 ◽

2008 ◽

Author(s):

Masa-Aki Tanaka ◽

Hiroyuki Ohshima ◽

Hideaki Monji

Keyword(s):

Numerical Simulation ◽

Heat Conduction ◽

Three Dimensional ◽

Piping System ◽

Fluid Temperature ◽

Numerical Schemes ◽

Simulation Code ◽

Simple Method ◽

Thermal Striping ◽

Les Model

In Japan Atomic Energy Agency (JAEA), simulation code “MUGTHES (MUlti Geometry simulation code for THErmal-hydraulic and Structure heat conduction analysis in boundary fitted coordinate)” has been developed to evaluate thermal striping phenomena that are caused by turbulence mixing of fluids in different temperature. MUGTHES employs Boundary Fitted Coordinate (BFC) system to treat complex geometries in power plants. And MUGTHES can deal with three-dimensional transient thermal-hydraulic problem coupled with three-dimensional transient heat conduction in the surrounding structure in consideration of conjugated heat transfer. In this paper, numerical schemes for thermal-hydraulic simulation employed in MUGTHES are described including LES model. A simple method to limit numerical oscillation is adopted in energy equation solving process. A new iterative method to solve Poisson equation in BFC system is developed for effective transient calculations. This method is based on BiCGSTAB method and SOR technique. As the code validation of MUGTHES, a numerical simulation in a T-junction piping system with LES approach was conducted. Numerical results related to velocity and fluid temperature distributions were compared with an existing water experimental data and the applicability of numerical schemes with LES model in MUGTHES to the thermal striping phenomenon was confirmed.

Download Full-text

Development of Numerical Simulation Method for Melt Relocation Behavior in Nuclear Reactors: Validation of Applicability for Actual Core Support Structures

Volume 3: Thermal-Hydraulics ◽

10.1115/icone24-60453 ◽

2016 ◽

Cited By ~ 2

Author(s):

Susumu Yamashita ◽

Kazuyuki Tokushima ◽

Masaki Kurata ◽

Kazuyuki Takase ◽

Hiroyuki Yoshida

Keyword(s):

Numerical Simulation ◽

High Temperature ◽

Computer Aided Design ◽

Nuclear Power ◽

Radiation Heat Transfer ◽

Three Dimensional ◽

Simulation Models ◽

Simulation Method ◽

Transfer Model ◽

Simulation Code

In order to precisely investigate molten core relocation behavior in the Fukushima Daiichi nuclear power station, we have developed the detailed and phenomenological numerical simulation code named JUPITER for predicting the molten core behavior including solidification and relocation based on the three-dimensional multiphase thermal-hydraulic simulation models. At the moment, multicomponent analysis method which can be treated any number of component as a fluid or solid body, Zr-water reaction model and simple radiation heat transfer model were implemented and showed that multicomponent melt flow and its solidification were confirmed in the simplified core structure system. However, the validation of the JUPITER using high temperature molten material has not been performed yet. In this paper, in order to evaluate the validity of the JUPITER, especially, for high temperature melt relocation experiment, we compared between numerical and experimental results for that system. As a result, qualitatively reasonable result was obtained. And also we performed melt relocation simulation on actual core structures designed by three dimensional CAD (Computer-Aided Design) and then we estimated phenomena which might be actually occurred in SAs.

Download Full-text

Numerical Simulation of Laser-Induced Bubble and Metal-Free Water Cannon

Journal of Advanced Computational Intelligence and Intelligent Informatics ◽

10.20965/jaciii.2021.p0050 ◽

2021 ◽

Vol 25 (1) ◽

pp. 50-55

Author(s):

Tomomasa Ohkubo ◽

Ei-ichi Matsunaga ◽

Yuji Sato ◽

◽

Keyword(s):

Numerical Simulation ◽

Dimensional Space ◽

Three Dimensional ◽

Free Water ◽

Qualitative Behavior ◽

Simulation Code ◽

Metal Free ◽

Laser Propulsion ◽

Three Dimensional Space ◽

Metallic Target

Laser propulsion is expected to be the next-generation propulsion mechanism. In particular, metal-free water cannon realizes propulsion without a metallic target. In this study, we develop a numerical simulation code using the C-CUP (CIP and Combined, Unified Procedure) method to simulate a laser-induced bubble and a metal-free water cannon. We successfully reproduced the qualitative behavior of spouting water in a three-dimensional space when the metal-free water cannon is irradiated by laser. Furthermore, the calculated results for the time development of displacement of the metal-free water cannon agree qualitatively with the experimental results. We simulate the behavior of the laser-induced bubble and discovered that the bubble inhales the water once spouted out, and the target moves backward owing to the pressure difference generated by the bubble expansion as well as collapsing and inhaling actions. Furthermore, the laser-induced bubble repeats the expansion and collapse, and the target moves forward while it oscillates.

Download Full-text

Visualizing Computational Simulation Results Using Virtual Reality Technology

Volume 2: Symposia, Parts A, B, and C ◽

10.1115/fedsm2003-45196 ◽

2003 ◽

Author(s):

Nilay Sezer-Uzol ◽

Anirudh Modi ◽

Lyle N. Long ◽

Paul E. Plassmann

Keyword(s):

Virtual Reality ◽

Large Scale ◽

Computational Simulation ◽

Three Dimensional ◽

Steering System ◽

General Purpose ◽

Parallel Computer ◽

Virtual Reality Technology ◽

Simulation Code ◽

Flow Simulations

The visualization of computational simulations of complex physical problems using virtual reality technology is demonstrated in this study. A general-purpose computational steering system (POSSE) which can be coupled to any C/C++ simulation code, has been developed and tested with a 3-D parallel Navier-Stokes flow solver (PUMA2) [1]. In addition, the visualizations can be displayed using virtual reality facilities (such as CAVEs and RAVEs) to better understand the 3-D nature of the flowfields. The simulations can be run on parallel computers such as Beowulf clusters, while the visualization is performed on other computers, through a client-server approach. A key advantage of our system is its scalability. Visualization primitives are generated on the parallel computer. This is essential for large-scale simulations, since it is often not possible to post-process the entire flowfield on a single computer due to memory and speed constraints. Example applications of time-dependent and three-dimensional computational flow simulations performed at Penn-State are presented to show the usefulness of POSSE and virtual reality systems. The examples include CFD predictions for unsteady simulations of a helicopter rotor, unsteady ship airwake simulations, helicopter tail fan-in-fin flow simulations and simulations of time-accurate flow and noise due to a landing gear.

Download Full-text

Numerical Simulation of the Backlayer Critical Velocity in the Memorial Tunnel Test (MTFVTP)

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2008-55256 ◽

2008 ◽

Author(s):

Eduardo Blanco ◽

Javier Cueto ◽

Joaqui´n Ferna´ndez ◽

Rau´l Barrio

Keyword(s):

Numerical Simulation ◽

Urban Areas ◽

Three Dimensional ◽

Numerical Procedure ◽

General Purpose ◽

Smoke Inhalation ◽

Road Transportation ◽

Long Distance ◽

Longitudinal Ventilation ◽

Road Tunnels

Road tunnels constitute key elements in the traffic net, especially for the long distance road transportation but also in the large urban areas. Although security preventions have permitted a relatively low index of accidents in tunnels, the analysis of the accidents in road tunnels during the last years shows an increment in both the number of cases and their gravity. In the case of fires, the control of the smoke propagation becomes crucial because the major risk for people is smoke inhalation rather than the direct exposure to the fire itself. Besides, a quick control of the fire requires that the access and evacuation routes are maintained without smoke. However, research in this field has been limited by the difficulties inherent in the problem, and so there are few experimental data available. This paper pursues the study of the control of the smoke propagation in tunnel roads with a longitudinal air stream. The methodology is based on the numerical simulation of the time evolution of the air and smoke flows induced after the onset of localized fires of different magnitude. Specifically, 10, 20, 50 and 100 MW fires were simulated. A general purpose computational fluid dynamics software is used for this investigation, due to its ability to model multi-species three-dimensional unsteady flows. The general purpose of the paper is the refinement and contrast of a numerical procedure for the simulation of fire tunnels with natural and longitudinal ventilation, as the particular case with the most complex and restrictive conditions, and the use of such procedure to study the backlayering phenomenon. The obtained results were compared with the natural and longitudinal ventilation tests of the Memorial Tunnel test as well as with previous studies.

Download Full-text