Bibliografías temáticas / CFD numerical simulation

Literatura académica sobre el tema "CFD numerical simulation"

Autor: Grafiati

Publicado: 22 de junio de 2024

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Artículos de revistas sobre el tema "CFD numerical simulation":

Zhang, Xinfang, Miao Li, Bomin Wang y Zexian Li. "A Parameter Correction method of CFD based on the Approximate Bayesian Computation technique". Journal of Physics: Conference Series 2569, n.º 1 (1 de agosto de 2023): 012076. http://dx.doi.org/10.1088/1742-6596/2569/1/012076.

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Abstract Numerical simulation and modeling techniques are becoming the primary research tools for aerodynamic analysis and design. However, various uncertainties in physical modeling and numerical simulation seriously affect the credibility of Computational Fluid Dynamics (CFD) simulation results. Therefore, CFD models need to be adjusted and modified with consideration of uncertainties to improve the prediction accuracy and confidence level of CFD numerical simulations. This paper presents a parameter correction method of CFD for aerodynamic analysis by making full use of the advantages of the Approximate Bayesian Computation (ABC) technique in dealing with the analysis and inference of complex statistical models, in which the parameters of turbulence models for CFD are inferenced. The proposed parameter correction method is applied to the aerodynamic prediction of the NACA0012 airfoil. The results show the feasibility and effectiveness of the proposed approach in improving CFD prediction accuracy.

Ohsaki, Shuji, Ryosuke Mitani, Saki Fujiwara, Hideya Nakamura y Satoru Watano. "Numerical Simulation of Particle Motions in Cascade Impactor and Human Respiratory System". MATEC Web of Conferences 333 (2021): 02013. http://dx.doi.org/10.1051/matecconf/202133302013.

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Dry powder inhalations (DPIs) have gathered attention as a treatment for respiratory diseases due to the large effective absorption area in a human lung. A cascade impactor is generally used to investigate the inhalation performance of DPIs. For the improvement of the efficiency of DPIs, understanding the particle motion and deposition behavior in the human lung and the cascade impactor is required. In the present study, computer simulations were conducted to calculate the particle motion and deposition behavior in the human lung and the cascade impactor. As simulation methods, a coupling model of a computational fluid dynamics and a discrete phase method (CFD−DPM) and a coupling model of a CFD and a discrete element method (CFD−DEM) were used. The CFD−DEM simulation could reproduce the experimental particle deposition behavior in the cascade impactor, although it was difficult by the CFD−DPM simulation. Furthermore, the calculation results using the CFD−DEM simulation quantitatively demonstrated the higher particle reachability into the simple lung model when smaller particles were used. It was found that the CFD−DEM simulation is a powerful tool to calculate the particle motion and deposition behavior in the cascade impactor and human lung.

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Scurtu, I. L. y M. I. Gheres. "Numerical evaluation of vehicles aerodynamics in platoon using CFD simulation". IOP Conference Series: Materials Science and Engineering 1220, n.º 1 (1 de enero de 2022): 012024. http://dx.doi.org/10.1088/1757-899x/1220/1/012024.

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Abstract Due to increased traffic and new technologies developed to improve road safety, a new vehicle driving technique is being studied. The vehicles’ platooning driving method has as objective to minimize the aerodynamic drag and therefore the fuel consumption. The aim of this study is to evaluate the distance between platoon traveling vehicles and to propose an optimal travel distance. The CFD evaluation is performed for two categories of vehicles at a given velocity and distance between them for two cases: in the first simulation scenario, a tractor-trailer is represented, followed by a SUV positioned at a given distance from the rear of the vehicle combination; in the second simulation, two tractor-trailers at the same boundary condition as for the first case are simulated. The vehicles models are made by using a CAD modelling environment, respecting the overall dimensions of an existing vehicle. The numerical evaluation of a distance between vehicle models is performed using the CFD method based on the Navier-Stokes equations averaging. The last part of the paper presents the interpretation of CDF simulation results, establishing the recommended travel distance between vehicles and conclusions of this study.

Laín-Beatove, Santiago, Manuel J. García.Ruiz, Brian Quintero-Arboleda y Santiago Orrego-Bustamante. "CFD Numerical simulations of Francis turbines". Revista Facultad de Ingeniería Universidad de Antioquia, n.º 51 (20 de marzo de 2013): 31–40. http://dx.doi.org/10.17533/udea.redin.14917.

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In this paper the description of the internal flow in a Francis turbine is addressed from a numerical point of view. The simulation methodology depends on the objectives. On the one hand, steady simulations are able to provide the hill chart of the turbine and energetic losses in its components. On the other hand, unsteady simulations are required to investigate the fluctuating pressure dynamics and the rotor-stator interaction. Both strategies are applied in this paper to a working Francis turbine in Colombia. The employed CFD package is ANSYS-CFX v. 11. The obtained results are in good agreement with the in site experiments, especially for the characteristic curve.

Shi, Xueqing, Daniel (Jian) Sun, Ying Zhang, Jing Xiong y Zhonghua Zhao. "Modeling Emission Flow Pattern of a Single Cruising Vehicle on Urban Streets with CFD Simulation and Wind Tunnel Validation". International Journal of Environmental Research and Public Health 17, n.º 12 (24 de junio de 2020): 4557. http://dx.doi.org/10.3390/ijerph17124557.

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Transportation has become one of the primary sources of urban atmospheric pollutants and it causes severe diseases among city residents. This study focuses on assessing the pollutant dispersion pattern using computational fluid dynamics (CFD) numerical simulation, with the effect and results validated by the results from wind tunnel experiments. First, the wind tunnel experiment was carefully designed to preliminarily assess the flow pattern of vehicle emissions. Next, the spatiotemporal distribution of pollutant concentrations around the motor vehicle was modeled using a CFD numerical simulation. The pollutant concentration contours indicated that the diffusion process of carbon monoxide mainly occurred in the range of 0−2 m above the ground. Meanwhile, to verify the correctness of the CFD simulation, pressure distributions of seven selected points that were perpendicular along the midline of the vehicle surface were obtained from both the wind tunnel experiment and the CFD numerical simulation. The Pearson correlation coefficient between the numerical simulation and the wind tunnel measurement was 0.98, indicating a strong positive correlation. Therefore, the distribution trend of all pressure coefficients in the numerical simulation was considered to be consistent with those from the measurements. The findings of this study could shed light on the concentration distribution of platoon-based vehicles and the future application of CFD simulations to estimate the concentration of pollutants along urban street canyons.

Lenhard, Richard, Katarína Kaduchová y Jozef Jandačka. "Numerical Simulation of Indirectly Heated Hot Water Heater". Advanced Materials Research 875-877 (febrero de 2014): 1693–97. http://dx.doi.org/10.4028/www.scientific.net/amr.875-877.1693.

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This paper describes a mathematical model of heating hot water for indirectly heated hot water heater. Using the established mathematical model was carried out simulation of the device to change its geometrical parameters. Based on the results of simulations was carried out optimization of indirectly heated hot water heater for hot water. Subsequently been made CFD simulations of the device, and those were compared with a mathematical model to verify the accuracy of the proposed mathematical model of heating hot water for indirectly heated hot water heater. Computational methods based on finite volume methods (CFD method) have proved very useful in optimizing indirectly heated hot water heater.

Grecu, I. S., G. Dunca, D. M. Bucur y M. J. Cervantes. "URANS numerical simulations of pulsating flows considering streamwise pressure gradient on asymmetric diffuser". IOP Conference Series: Earth and Environmental Science 1079, n.º 1 (1 de septiembre de 2022): 012087. http://dx.doi.org/10.1088/1755-1315/1079/1/012087.

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Abstract The paper focuses on implementing the wall model developed by Manhart, in Reynolds Averaged Navier - Stokes (RANS) turbulence models used in the field of Computational Fluid Dynamics (CFD). This wall model considers the influence of the streamwise pressure gradient in addition to the existing wall models used in the usual CFD codes. In the present work, two RANS numerical simulations are carried out using the k-ω Shear Stress Transport (SST) turbulence model on an asymmetric diffuser geometry. One numerical simulation is carried out using the implementation of the Manhart wall model in the k-ω SST turbulence model, and the other numerical simulation is performed using the standard formulation of the k-ω SST turbulence model. The numerical simulations carried out using the Manhart wall model and the standard formulation of the k-ω SST are compared with experimental measurements made on the asymmetric diffuser experimental installation. The numerical simulations are carried out using a free, open-source CFD tool, Code_Saturne. The comparisons between numerical simulations and the experimental data are in good agreement in the boundary layer of the flow inside the diffuser. The Manhart wall model had a faster convergence resulting in a shorter simulation time.

Shaheed, Aya kh y Riyadh Z. Azzubaidi. "CFD Simulation Model of Salt Wedge Propagation". Journal of Engineering 28, n.º 1 (1 de enero de 2022): 76–85. http://dx.doi.org/10.31026/j.eng.2022.01.06.

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This study aims to numerically simulate the flow of the salt wedge by using computational fluid dynamics, CFD. The accuracy of the numerical simulation model was assessed against published laboratory data. Twelve CFD model runs were conducted under the same laboratory conditions. The results showed that the propagation of the salt wedge is inversely proportional to the applied freshwater discharge and the bed slope of the flume. The maximum propagation is obtained at the lowest discharge value and the minimum slope of the flume. The comparison between the published laboratory results and numerical simulation shows a good agreement. The range of the relative error varies between 0 and 16% with an average of 2% and a root mean square error of 0.18. Accordingly, the CFD software is quite valid to simulate the propagation of the salt wedge.

Sandham, N. D., M. Alam y S. Morin. "Embedded direct numerical simulation for aeronautical CFD". Aeronautical Journal 105, n.º 1046 (abril de 2001): 193–98. http://dx.doi.org/10.1017/s0001924000025434.

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Abstract A method is proposed by which a direct numerical simulation of the compressible Navier-Stokes equations may be embedded within a more general aeronautical CFD code. The method may be applied to any code which solves the Euler equations or the Favre-averaged Navier-Stokes equations. A formal decomposition of the flowfield is used to derive modified equations for use with direct numerical simulation solvers. Some preliminary applications for model flows with transitional separation bubbles are given.

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Tesis sobre el tema "CFD numerical simulation":

Choi, Hong Fei. "Numerical simulation of atrium fire using two CFD tools". Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1694321.

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Karlsson, Karl. "Numerical Simulation of Sabot Discard Projectile". Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79248.

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When designing an armour piercing kinetic energy projectile with a discarding sabot, it is important to know how the projectile is affected by the sabot during the discard. If the projectile has no active guiding systems, small disturbances to the initial flight path of the projectile can result in a significant deviance from its intended target. To investigate whether the discard process and its effect on a projectile could be simulated a CFD model was built based on a generic design for an APFSDS projectile for the Carl Gustaf M4 system built by Saab Dynamics AB. The model had to replicate the course of a sabot discard as accurately as possible and be able to track how it affects the projectile. ANSYS Fluent was used to build a model of a quarter of the design incorporating one of the four sabot petals and the part of the projectile in between two of its four fins, utilizing symmetry at zero angle of attack. To achieve a realistic discard process, fluents 6DOF solver was used allowing the sabot to discard due to aerodynamic loads rather than by following a pre-determined path. To allow the components to move inside the domain an overset interface was implemented around the sabot to allow the mesh to update itself during the simulation, keeping its quality consistent. The models initial stage includes a small gap between the sabot and projectile which is necessary to avoid contact which causes issues with mesh creation and divergence. The projectile geometry was based on rough estimates of how a fin stabilized projectile for the M4 would look whereas the sabot design was based on earlier sabot designs and iterated to achieve a discard phase with no contact. The iterative process which produced the sabot design proved that its geometry greatly affects how it discards from the projectile. To track how the projectile is affected during the discard, the forces and moments applied to the projectile from the flow including its interaction with the sabot were tracked. To compare there forces and moments for different discard courses, the sabots centre of gravity was changed to provoke it to discard differently. The model showed a clear difference in how the projectile was affected by the flow during the different discards. This shows the importance of designing the sabot to discard cleanly and quickly so as to not alter the trajectory of the projectile in flight. Also investigated was the effect of the initial gap on the course of the discard. Adding the gap is a simplification which should affect the discard so that it no longer matches a physical test case and so will have to be tuned to find what gap provides the most realistic discard. Although this model could not be validated given the lack of a physical counterpart, it could be determined that the gap greatly affects the discard and that this model is very sensitive to the initial load put on the sabot. Before the model can be used for concept development, a few things need to be worked out. These include a contact definition, inner ballistic effects and building a model that can be test fired to generate validationdata.

Crozon, Clément. "Coupling flight mechanics and CFD : numerical simulation of shipborne rotors". Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2030079/.

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This thesis demonstrates the use of Computational Fluid Dynamics (CFD) for the simulation of manoeuvring helicopters. Results are presented for the problem of shipborne operations, for which a literature survey showed that little work has been carried out. The CFD solver HMB2 was first validated using available experimental data for isolated ship wakes and helicopter loads at low advance ratios. A rotorcraft flight mechanics model was then developed and integrated into HMB2. The model includes a trimming method and a linearisation routine based on finite differences. The linear model of the aircraft can be used to estimate the controls applied by the pilot during a prescribed manoeuvre via the use of the SYCOS inverse-simulation method or via an LQR auto-pilot. The methods developed in the framework of this thesis include a general multi-body grid motion and an alternative formulation for earth-fixed frame of reference in the CFD. A study of the ship/rotor wake interaction was carried out using the actuator disc method that approximated the effect of the rotor, in a steady fashion and without resolving the flow around the blades. Various positions and thrust of the rotor were tested and the flowfield obtained via coupled simulations were compared with those obtained by super-imposing isolated rotor and ship flowfields. The results show that the superposition principle is not valid and leads to flowfields that have little to do with the real flow that is dominated by the interaction of helicopter and ship airwakes. The case of a rotor hovering in close proximity to a frigate deck was reproduced with fullyresolved blades, and the results shows a significant reduction of thrust due to the flow topology behind the hangar. The Helicopter Flight Mechanics (HFM) method was tested by simulating the aircraft response to a collective pilot input, using simplified models and coupled with CFD. Then, the coupled HFM/HMB2 method was used, in conjunction with the LQR auto-pilot, to simulate the phase of landing of a Sea King helicopter. Simulations were carried-out in free-air and above the frigate deck and the specified trajectories were followed adequately. Results for the ship landing show that the wake of the ship alters the obtained landing trajectory and that the current method captures some of the effects of the wake interaction.

Cox-Stouffer, Susan K. Jr. "Numerical Simulation of Injection and Mixing in Supersonic Flow". Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/29628.

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A numerical investigation of the performance of two candidate designs for injection into supersonic flow, including a comparison of two renormalized group theory (RNG) based k-epsilon turbulence models with a more conventional k-epsilon model. The chosen designs were an unswept ramp injector with four injection ports and a novel nine-hole injector array. The objectives of the investigation were to provide reliable computational solutions to the flowfields in question using both RNG and standard k-epsilon turbulence models and to compare the solutions to experiment, thereby to judge the relative performance of the turbulence models. A second objective of the investigation was to use the computed data to provide design insights for the nine-hole injector array. This investigation made use of GASP(tm) version 2.2, a commercial computational fluid dynamics code that was augmented by the addition of one RNG-based k-epsilon turbulence model derived by Zhou, et. al. and one variant of Zhou's model, which was derived by the author. Mesh sequencing studies were performed to measure solution quality, with the fine mesh for the injector array containing roughly one million grid nodes and the fine mesh for the ramp injector containing more than six million grid nodes. Results of these studies indicated that the injector-array solution was significantly under-resolved in the farfield, though the quality was better in the vicinity of the injector itself. The ramp-injector solution, while not perfectly grid-resolved, showed much better grid convergence in both the nearfield and farfield. Accordingly, comparison with experiment was better for the ramp injector than for the injector array. For both injectors, the differences between solutions generated with RNG-based k-epsilon and standard k-epsilon turbulence models were negligibly small." Despite inadequate grid resolution in the farfield, the computational investigation of the nine-hole injector array did yield several important design insights. Particularly, the significance to mixing and losses of the placement of the outer injectors of the second and third rows was determined.
Ph. D.

Li, Ning. "Comparison between three different CFD software and numerical simulation of an ambulance hall". Thesis, KTH, Energiteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160938.

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Ambulance hall is a significant station during emergency treatment. Patients need to be transferred from ambulance cars to the hospital’s building in the hall. Eligible performance of ventilation system to supply satisfied thermal comfort and healthy indoor air quality is very important. Computational fluid dynamic (CFD) simulation as a broadly applied technology for predicting fluid flow distribution has been implemented in this project. There has two objectives for the project. The first objective is to make comparison between the three CFD software which consists of ANSYS Fluent, Star-CCM+ and IESVE Mcroflo according to CFD modeling of the baseline model. And the second objective is to build CFD modeling for cases with difference boundary conditions to verify the designed ventilation system performance of the ambulance hall. In terms of simulation results from the three baseline models, ANSYS Fluent is conclusively recommended for CFD modeling of complicated indoor fluid environment compared with Star-CCM+ and IESVE Microflo. Regarding to the second objective, simulation results of case 2 and case 3 have shown the designed ventilation system for the ambulance hall satisfied thermal comfort level which regulated by ASHRAE standard with closed gates. Nevertheless, threshold limit value of the contaminants concentration which regulated by ASHRAE IAQ Standard cannot be achieved. From simulation results of case 4.1 to 4.3 shown that the designed ventilation system cannot satisfy indoor thermal comfort level when the gates of the ambulance hall opened in winter. In conclusion, measures for decreasing contaminants concentration and increasing indoor air temperature demanded to be considered in further design.

El, Mellas Ismail. "Numerical simulation of wax deposition in pipelines". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

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Crude oils are complex mixtures of hydrocarbons. Among these components, high molecular weight paraffin (waxes) and asphaltenes may cause severe flow assurance issues in production and transportation subsea pipeline systems. Wax molecules are dissolved in the crude oil, when the temperature decreases, the solubility of high molecular weight paraffins decreases rapidly, and this results in the formation of gels of complex morphology, that deposit on the cold walls of the subsea pipelines during the flow of waxy crude oils, and this is a big problem for the subsea pipelines. The cost of wax management is enormous and rapidly increasing because of increased oil production in deep-sea areas. In this work, is presented a new numerical model for predicting wax deposition in oil pipes. While the almost part of the models existing in the literature are based on a separated two-fluid description of the oil/wax-oil flow, the model proposed is based on a mixture description, where wax is considered as a suspended phase surrounded by crude oil. When wax separates in the crude oil, the mixture becomes a gel-like fluid, and this mechanism is incorporated in the flow model by a specific rheological model where the mixture viscosity depends on both the local wax concentration and its “age”. In order to simultaneously model moving regions of different “ages”, our model solves a transport equation for the ageing time. Deposition is modelled by solving wax mass balance, dissolved asphaltenes mass balance, and energy. Wax generation and asphaltenes removal are modelled as a first-order reaction coupling mass balance between the species, where the local equilibrium saturation is given as a function of the mixture temperature. In this work, is present the implementation of the model in the open-source C++ library OpenFOAM and validation of the model between some similar works. Besides a discussion of the results for wax deposition and a parametric study about the critical parameters.

Henson, Jonathan Charles. "Numerical simulation of spark ignition engines with special emphasis on radiative heat transfer". Thesis, Loughborough University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297589.

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Hayati, Abolfazl. "NUMERICAL STUDY OF 2D PARTICLE FLOW IN A DUCT". Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-13324.

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Reasor, Jr Daniel A. "NUMERICAL SIMULATION OF TWO FLOW CONTROL APPROACHES FOR LOW REYNOLDS NUMBER APPLICATIONS". UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/461.

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Current research in experimental and computational fluid dynamics is focused in the area of flow control. Flow control devices are usually classified as either passive or active. Plasma actuators are active flow control devices that require input from an external power source. Current efforts have modeled the effects of plasma actuators as a body force near the electrode. The research presented herein focuses on modeling the fluid-plasma interaction seen in dielectric barrier discharge plasma actuators as a body force vector in the region above the embedded electrode using computational fluid dynamics (CFD). This body force is modeled as the product of the gradient of the potential due to the electric field and the net charge density. In a passive flow control study, two-dimensional simulations using CFD are done with a smooth and bumpy Eppler 398 airfoil with laminar, transition, and turbulent models in an effort to improve the understanding of the flow over bumpy airfoils and to quantify the advantages or disadvantages of the bumps.

Kara, Sibel. "Numerical simulation of flow in open-channels with hydraulic structures". Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54033.

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Extreme hydrological events associated with global warming are likely to produce an increasing number of flooding scenarios resulting in significant bridge inundation and associated damages. During large floods, the presence of a bridge in an open channel triggers a highly turbulent flow field including 3D complex coherent structures around bridge structures. These turbulence structures are highly energetic and possess high sediment entrainment capacity which increases scouring around the bridge foundation and consequently lead to structural stability problems or even failure of the structure. Hence, understanding the complex turbulent flow field for these extreme flow conditions is crucial to estimate the failure risks for existing bridges and better design of future bridges. This research employs the method Large Eddy Simulation (LES) to predict accurately the 3D turbulent flow around bridge structures. The LES code is refined with a novel free surface algorithm based on the Level Set Method (LSM) to determine the complex water surface profiles. The code is used to analyze the hydrodynamics of compound channel flow with deep and shallow overbanks, free flow around a bridge abutment, pressure flow with a partially submerged bridge deck and bridge overtopping flow. All simulations are validated with data from complementary physical model tests under analogous geometrical and flow conditions. Primary velocity, bed shear stress, turbulence characteristics and 3D coherent flow structures are examined thoroughly for each of the flow cases to explain the hydrodynamics of these complex turbulent flows.

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Libros sobre el tema "CFD numerical simulation":

Nastac, Laurentiu. CFD modeling and simulation in materials processing. Hoboken, N.J: John Wiley & Sons, 2012.

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K, Sweby Peter y Research Institute for Advanced Computer Science (U.S.), eds. Dynamics of numerics & spurious behaviors in CFD computations. [Moffett Field, Calif.]: Research Institute for Advanced Computer Science, NASA Ames Research Center, 1997.

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Brandt, Achi. Barriers in achieving textbook multigrid efficiency (TME) in CFD. Hampton, Va: Institute for Computer Applications in Science and Engineering, NASA Langley Research Center, 1998.

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Laurentiu, Nastac, Li Ben Q, Minerals, Metals and Materials Society. Extraction and Processing Division, Minerals, Metals and Materials Society. Light Metals Division., Minerals, Metals and Materials Society. Materials Processing and Manufacturing Division., Minerals, Metals and Materials Society. Meeting, Symposium on CFD Modeling and Simulation of Engineering Processes (2004 : Charlotte, North Carolina) y Symposium on Multi-scale Phenomena in Materials Processing (2004 : Charlotte, North Carolina), eds. Multiphase phenomena and CFD modeling and simulation in materials processing: Proceedings of symposium [sic] held at the 2004 TMS Annual Meeting, Charlotte, North Carolina, U.S.A., March 14-18, 2004. Warrendale, Pennsylvania: TMS, 2004.

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Norbert, Kroll y Fassbender Jens K, eds. MEGAFLOW - numerical flow simulation for aircraft design: Results of the second phase of the German CFD initiative MEGAFLOW, presented during its closing symposium at DLR, Braunschweig, Germany, December 10 and 11, 2002. Berlin: Springer, 2005.

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Hu, Ping. Theories, Methods and Numerical Technology of Sheet Metal Cold and Hot Forming: Analysis, Simulation and Engineering Applications. London: Springer London, 2013.

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Lirkov, Ivan. Large-Scale Scientific Computing: 8th International Conference, LSSC 2011, Sozopol, Bulgaria, June 6-10, 2011, Revised Selected Papers. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012.

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Silber, Gerhard. Preventive Biomechanics: Optimizing Support Systems for the Human Body in the Lying and Sitting Position. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013.

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Capítulos de libros sobre el tema "CFD numerical simulation":

Grewal, H. S., H. Singh y Anupam Agrawal. "Numerical Simulation of Erosion Using Computational Fluid Dynamics". En CFD Modeling and Simulation in Materials Processing, 89–96. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118364697.ch11.

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Perakis, Nikolaos y Oskar J. Haidn. "Experimental and Numerical Investigation of CH$$_4$$/O$$_2$$ Rocket Combustors". En Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 359–79. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53847-7_23.

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Abstract The experimental investigation of sub-scale rocket engines gives significant information about the combustion dynamics and wall heat transfer phenomena occurring in full-scale hardware. At the same time, the performed experiments serve as validation test cases for numerical CFD models and for that reason it is vital to obtain accurate experimental data. In the present work, an inverse method is developed able to accurately predict the axial and circumferential heat flux distribution in CH$$_4$$/O$$_2$$ rocket combustors. The obtained profiles are used to deduce information about the injector-injector and injector-flame interactions. Using a 3D CFD simulation of the combustion and heat transfer within a multi-element thrust chamber, the physical phenomena behind the measured heat flux profiles can be inferred. A very good qualitative and quantitative agreement between the experimental measurements and the numerical simulations is achieved.

Sin, V. K., L. M. Tarn, S. K. Lao y H. F. Choi. "Numerical Simulation of Atrium Fire using Two CFD Tools". En Computational Methods in Engineering & Science, 170. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/978-3-540-48260-4_16.

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Agaliotis, Eliana, Mario Rosenberger, Alicia E. Ares y Carlos Schvezov. "Numerical Modeling of the Interaction between a Foreign Particle an Solidifying Crystalline Interface". En CFD Modeling and Simulation in Materials Processing, 171–78. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118364697.ch20.

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Nastac, Laurentiu. "Numerical Simulation of Macro-shrinkage and Micro-shrinkage in A356 Sand Mold Castings". En CFD Modeling and Simulation in Materials Processing, 205–12. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118364697.ch24.

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Li, Baokuan, Fang Wang y Meilong Shan. "Numerical Analysis of Electromagnetic Field in an Electroslag Remelting Process with Three-Phases Electrodes". En CFD Modeling and Simulation in Materials Processing, 131–38. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118364697.ch16.

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Liu, Shupei, Bo Wang, Zhiliang Yang, Shuai Feng, Kongfang Feng, Jinyin Xie y Jieyu Zhang. "Numerical Simulation of the Multiphase Flow in the Single-Tundish System". En CFD Modeling and Simulation in Materials Processing 2016, 67–74. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2016. http://dx.doi.org/10.1002/9781119274681.ch9.

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Boussaa, R., O. Budenkova, L. Hachaniu, X.-D. Wang, B. Saadi, K. Zaidat, H. Ben Hadid y Y. Fautrelle. "2D and 3D Numerical Modeling of Solidification Benchmark of Sn-3Pb (%wt.) Alloy under Natural Convection". En CFD Modeling and Simulation in Materials Processing, 163–70. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118364697.ch19.

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Cox, Michael R. y Gregory M. Poole. "Numerical Simulation of Electromagnetic and Heat Transfer Phenomena in Inductively Heated Risers". En CFD Modeling and Simulation in Materials Processing 2018, 53–62. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-72059-3_6.

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Li, An-Zheng, Shi-Jin Feng y Ben-Yi Cao. "Numerical Simulation of Bioreactor Landfills Subjected to Aeration Using CFD". En Proceedings of the 8th International Congress on Environmental Geotechnics Volume 2, 224–30. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-2224-2_28.

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Actas de conferencias sobre el tema "CFD numerical simulation":

Chen, Jun y Xiong Shi. "CFD Numerical Simulation of Exhaust Muffler". En 2011 Seventh International Conference on Computational Intelligence and Security (CIS). IEEE, 2011. http://dx.doi.org/10.1109/cis.2011.321.

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Sadathosseini, S. H., S. M. Mousaviraad y M. H. Sadr. "Numerical Simulation of Free Surface Flow Around A Surface Piercing Naca0024 Hydrofoil". En CFD 2005- CFD Technology in Ship Hydrodynamics. RINA, 2005. http://dx.doi.org/10.3940/rina.cfd.2005.4.

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Raczynski, Stanislaw. "FLUIDS6: CFD Multiprocessing, Numerical Problems, New Features". En 25th Conference on Modelling and Simulation. ECMS, 2011. http://dx.doi.org/10.7148/2011-0249-0253.

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Yang, Weimin, Yanna Zhang, Shujiang Li y Caixia Shi. "The CFD Numerical Simulation of H-Boat". En 2015 International Conference on Automation, Mechanical Control and Computational Engineering. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/amcce-15.2015.303.

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Mahu, R., F. Popescu, F. Frunzulic̀, Al Dumitrache, Theodore E. Simos, George Psihoyios, Ch Tsitouras y Zacharias Anastassi. "3D CFD Modeling and Simulation of NREL Phase VI Rotor". En NUMERICAL ANALYSIS AND APPLIED MATHEMATICS ICNAAM 2011: International Conference on Numerical Analysis and Applied Mathematics. AIP, 2011. http://dx.doi.org/10.1063/1.3637914.

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Mohamed, Bashir, Abdelsalam N. Abugharara, M. A. Rahman y Stephen D. Butt. "CFD Numerical Simulation for Downhole Thruster Performance Evaluation". En ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-78101.

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This study focuses on numerical simulation and evaluation of a hydraulically powered downhole Thruster. This device is numerically simulated and evaluated using ANSYS Fluent 17.2 to show its generation of pressure pulses that can induce downhole forces that magnify the downhole dynamic weight on bit (DWOB) using drilling mud. Such magnification of the DWOB can produce axial motion of the Thruster. Such axial motions, as proved by many publications can improve the drilling rate of penetration (ROP), release stuck pipes, and reduce frictions in non-vertical wells. The special inner design of the Thruster creates pressure pulses that can provide load impact on the drill bit leading to the increase of WOB that can enhance the drilling performance. The current stage of the study of the Thruster involves a mechanical design of the Thruster by the SolidWorks and an evaluation of the tool function and performance through pressure effect simulation by ANSYS Fluent 17.2. Initially, water is used as the fluid and the main parameters involved in the analysis are pressure and velocity. However, power-law as a non-Newtonian fluid is also used for comparison study in the section of pressure drop analysis. The results are analyzed based on velocity pressure profiles, pressure drops, pressure effects with applications of various back pressures at several planes using water and power-law fluids.

Ni, William W. "CFD Numerical Simulation Aero-engine Air-Oil Separator". En AeroTech. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2022. http://dx.doi.org/10.4271/2022-01-0027.

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Guilmineau, Emmanuel. "Numerical Simulation of Flow Around a Generic Pickup With ISIS-CFD". En ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting collocated with 8th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2010. http://dx.doi.org/10.1115/fedsm-icnmm2010-30680.

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Computational Fluid Dynamics (CFD) is used to simulate the flow over a pickup truck. The flow solver used is ISIS-CFD developed by the CFD Department of the Fluid Mechanics Laboratory of Ecole Centrale de Nantes. CFD simulations are carried out with the Explicit Algebraic Reynolds Stress Model (EARSM) turbulence model and the Detached Eddy Simulation (DES). The focus of the simulation is to assess the capabilities of ISIS-CFD for vehicle aerodynamic development for pickup trucks. Detailed comparisons are made between the CFD simulations and the existing experiments for a generic pickup truck. The comparisons between the simulation results and the time-averaged measurements reveals that the CFD calculations are able to track the flow trends.

Wang, Zhihua, Hehui Wang, Chaoping Wang, Chunhui Fu y Pangu Lu. "Numerical simulation of pipeline ultrasonic cavitation based on CFD". En 2nd International Conference on Advances in Mechanical Engineering and Industrial Informatics (AMEII 2016). Paris, France: Atlantis Press, 2016. http://dx.doi.org/10.2991/ameii-16.2016.118.

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Zhao, Jianping y Xuechao Wang. "CFD Numerical Simulation of the Submarine Pipeline With Spoiler". En ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61462.

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Submarine pipeline is one of the most important oil transportation components, pipeline failure due to over-span is the most serious failure mechanism. There are four reasons of pipeline span formation, including erosion of seabed, bumpy seabed, submarine pipeline climbing slope, and pipeline ascending to offshore platform. The Hangzhou Bay submarine pipeline is the most important subproject of the Yong-Hu-Ning network, and it is also the biggest long-distance pipeline for crude oil in China. Due to the dynamic nature of Hangzhou Bay, including high tides and high current amplified by the shallow waters, a self-burial method was selected as the best solution. By increasing the velocity of the stream between the pipeline and the seabed, shear stress on the seabed was enhanced. This localized increase in shear stress causes the seabed under the pipe to erode more quickly and facilitates self-burial of the pipe. To facilitate self-burial, a non-metallic vertical fin is fastened to the top of the pipeline. In this paper flow around a pipeline with and without a spoiler near a smooth wall is simulated with FLUENT version 6.1. The influences of the spoiler on pressure coefficient, lift coefficient, shear stress on the wall, as well as velocity profile are investigated. It is indicated that the coefficients for Drag and Inertia are increased with the application of the spoiler. The lift coefficient is reversed with the application of the spoiler increases the stability of the pipeline resulting in the reduction of the required coating weight.

Informes sobre el tema "CFD numerical simulation":

Aursjø, Olav, Aksel Hiorth, Alexey Khrulenko y Oddbjørn Mathias Nødland. Polymer flooding: Simulation Upscaling Workflow. University of Stavanger, noviembre de 2021. http://dx.doi.org/10.31265/usps.203.

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There are many issues to consider when implementing polymer flooding offshore. On the practical side one must handle large volumes of polymer in a cost-efficient manner, and it is crucial that the injected polymer solutions maintain their desired rheological properties during transit from surface facilities and into the reservoir. On the other hand, to predict polymer flow in the reservoir, one must conduct simulations to find out which of the mechanisms observed at the pore and core scales are important for field behavior. This report focuses on theoretical aspects relevant for upscaling of polymer flooding. To this end, several numerical tools have been developed. In principle, the range of length scales covered by these tools is extremely wide: from the nm (10-9 m) to the mm (10-3 m) range, all the way up to the m and km range. However, practical limitations require the use of other tools as well, as described in the following paragraphs. The simulator BADChIMP is a pore-scale computational fluid dynamics (CFD) solver based on the Lattice Boltzmann method. At the pore scale, fluid flow is described by classical laws of nature. To a large extent, pore scale simulations can therefore be viewed as numerical experiments, and they have great potential to foster understanding of the detailed physics of polymer flooding. While valid across length scales, pore scale models require a high numerical resolution, and, subsequently, large computational resources. To model laboratory experiments, the NIORC has, through project 1.1.1 DOUCS, developed IORCoreSim. This simulator includes a comprehensive model for polymer rheological behavior (Lohne A. , Stavland, Åsen, Aursjø, & Hiorth, 2021). The model is valid at all continuum scales; however, the simulator implementation is not able to handle very large field cases, only smaller sector scale systems. To capture polymer behavior at the full field scale, simulators designed for that specific purpose must be used. One practical problem is therefore: How can we utilize the state-of-the-art polymer model, only found in IORCoreSim, as a tool to decrease the uncertainty in full field forecasts? To address this question, we suggest several strategies for how to combine different numerical tools. In the Methodological Approach section, we briefly discuss the more general issue of linking different scales and simulators. In the Validation section, we present two case studies demonstrating the proposed strategies and workflows.

Allen, Luke, Joon Lim, Robert Haehnel y Ian Detwiller. Rotor blade design framework for airfoil shape optimization with performance considerations. Engineer Research and Development Center (U.S.), junio de 2021. http://dx.doi.org/10.21079/11681/41037.

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A framework for optimizing rotor blade airfoil shape is presented. The framework uses two digital workflows created within the Galaxy Simulation Builder (GSB) software package. The first is a workflow enabling the automated creation of a surrogate model for predicting airfoil performance coefficients. An accurate surrogate model for the rapid generation of airfoil coefficient tables has been developed using linear interpolation techniques that is based on C81Gen and ARC2D CFD codes. The second workflow defines the rotor blade optimization problem using GSB and the Dakota numerical optimization library. The presented example uses a quasi-Newton optimization algorithm to optimize the tip region of the UH-60A main rotor blade with respect to vehicle performance. This is accomplished by morphing the blade tip airfoil shape for optimum power, subject to a constraint on the maximum pitch link load.

Rahai, Hamid y Jeremy Bonifacio. Numerical Investigations of Virus Transport Aboard a Commuter Bus. Mineta Transportation Institute, abril de 2021. http://dx.doi.org/10.31979/mti.2021.2048.

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The authors performed unsteady numerical simulations of virus/particle transport released from a hypothetical passenger aboard a commuter bus. The bus model was sized according to a typical city bus used to transport passengers within the city of Long Beach in California. The simulations were performed for the bus in transit and when the bus was at a bus stop opening the middle doors for 30 seconds for passenger boarding and drop off. The infected passenger was sitting in an aisle seat in the middle of the bus, releasing 1267 particles (viruses)/min. The bus ventilation system released air from two linear slots in the ceiling at 2097 cubic feet per minute (CFM) and the air was exhausted at the back of the bus. Results indicated high exposure for passengers sitting behind the infectious during the bus transit. With air exchange outside during the bus stop, particles were spread to seats in front of the infectious passenger, thus increasing the risk of infection for the passengers sitting in front of the infectious person. With higher exposure time, the risk of infection is increased. One of the most important factors in assessing infection risk of respiratory diseases is the spatial distribution of the airborne pathogens. The deposition of the particles/viruses within the human respiratory system depends on the size, shape, and weight of the virus, the morphology of the respiratory tract, as well as the subject’s breathing pattern. For the current investigation, the viruses are modeled as solid particles of fixed size. While the results provide details of particles transport within a bus along with the probable risk of infection for a short duration, however, these results should be taken as preliminary as there are other significant factors such as the virus’s survival rate, the size distribution of the virus, and the space ventilation rate and mixing that contribute to the risk of infection and have not been taken into account in this investigation.

Ginis, Isaac, Deborah Crowley, Peter Stempel y Amanda Babson. The impact of sea level rise during nor?easters in New England: Acadia National Park, Boston Harbor Islands, Boston National Historical Park, and Cape Cod National Seashore. National Park Service, 2024. http://dx.doi.org/10.36967/2304306.

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This study examines the potential impact of sea level rise (SLR) caused by climate change on the effects of extratropical cyclones, also known as nor?easters, in four New England coastal parks: Acadia National Park (ACAD), Boston Harbor Islands National Recreation Area (BOHA), Boston National Historical Park (BOST) and Cape Cod National Seashore (CACO). A multi-method approach is employed, including a literature review, observational data analysis, coupled hydrodynamic-wave numerical modeling, 3D visualizations, and communication of findings. The literature review examines previous studies of nor?easters and associated storm surges in New England and SLR projections across the study domain due to climate change. The observational data analysis evaluates the characteristics of nor?easters and their effects, providing a basis for validating the model. Numerical modeling is performed using the Advanced Circulation (ADCIRC) model, coupled with the Simulating Waves in the Nearshore (SWAN) model to simulate storm surges and waves. The model was validated against available observations and demonstrated its ability to simulate water levels, inland inundation, and wave heights in the study area with high accuracy. The validated model was used to simulate three powerful nor?easters (April 2007, January 2018, and March 2018) and each storm was simulated for three sea levels, (1) a baseline mean sea level representative of the year 2020, as well as with a (2) 1 ft of SLR and (3) 1 m of SLR. Analysis of the model output was used to assess the vulnerability of the parks to nor?easters by examining peak impacts in the park areas. Additional simulations were conducted to evaluate the role of waves in predicting peak water levels and the impact of inlet configurations on storm surges within coastal embayments behind the barrier beach systems in the southern Cape Cod region. The project developed maps, three-dimensional visualizations, and an interpretive film to assist the parks in planning for resource management, maintenance, emergency management, visitor access, safety, education, and outreach. These tools provide a better understanding of the potential impacts of nor?easters and SLR and enable the parks to better prepare for future storms.

Ding, Yan, Q. Chen, Ling Zhu, Julie Rosati y Bradley Johnson. Implementation of flexible vegetation into CSHORE for modeling wave attenuation. Engineer Research and Development Center (U.S.), febrero de 2022. http://dx.doi.org/10.21079/11681/43220.

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This technical report presents the new numerical modeling capabilities for simulating wave attenuation and mean water level changes through flexible vegetation such as smooth cordgrass in coastal and marine wetlands. These capabilities were implemented into the Cross-SHORE (CSHORE) numerical model. The biomechanical properties of vegetation such as dimensions, flexibility, and bending strength are parameterized in terms of the scaling law. Correspondingly, a new formulation of the vegetation drag coefficient, CD, is developed using field data from a salt marsh in Terrebonne Bay, LA, by considering spatially varying effective stem and blade heights of species. This report also presents a general procedure for using the model to simulate hydrodynamic variables (i.e., waves, currents, mean water levels) at vegetated coasts, which are used to quantify the effects of wave attenuation and reduction of surge and runup due to vegetation. Preliminary model validation was conducted by simulating a set of laboratory experiments on synthetic vegetation, which mimicked the flexibility of Spartina alterniflora. The validation results indicate that the newly developed vegetation capabilities enable CSHORE to predict changes of wave heights and water levels through marshes by considering species-specific biomechanical features. The model is also applicable to assess vegetation effectiveness against waves and surges.

Rahai, Hamid y Jeremy Bonifacio. Virus Control Aboard a Commuter Bus. Mineta Transporation Institute, octubre de 2023. http://dx.doi.org/10.31979/mti.2023.2248.

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A major health concern for public transit users is exposure to viruses from other passengers. This numerical study examines virus containment aboard a public bus with changes to the bus ventilation system. The virus was modeled as a 2.5 µm round solid particle released from the mouth of the infectious passenger at a rate of 21 particles per second at a mouth velocity of 0.278 m/sec. The air delivery to the cabin was two linear ceiling slots spanning the length of the bus delivering 59.38 m3/min (2,097 CFM) of air at a mean velocity of 1 m/sec. Two different axial and vertical linear exhaust slots placed on the side walls were investigated to examine how they affected virus containment and spread to the other parts of the cabin. Simulations were performed for both cases of the bus in transit and at the bus stop when the drop-off door was opened. Results indicate during transit that virus spread was contained to passengers sitting immediately in front of and behind the infectious passenger and the level of virus concentration could merit an increased risk of infection with increased virus residence time. However, augmented air mixing was observed between inside and outside air during the passenger drop-off with viruses spread to the front and back of the bus with reduced concentration and risk of infection. Analytical analyses of the risk of infection using the Wells-Riley equation were performed for the bus ventilation using 100% recirculating air without filtration, and 50% and 100% fresh air ventilation. Results indicate a high risk of infection when recirculating air is used, but the risk is reduced significantly with 50% and 100% fresh air ventilation. These results are critical to informing bus manufacturers, transit agencies, planners, and public transportation users about the potential of virus containment using a new ventilation system.

Warrick, Arthur W., Gideon Oron, Mary M. Poulton, Rony Wallach y Alex Furman. Multi-Dimensional Infiltration and Distribution of Water of Different Qualities and Solutes Related Through Artificial Neural Networks. United States Department of Agriculture, enero de 2009. http://dx.doi.org/10.32747/2009.7695865.bard.

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The project exploits the use of Artificial Neural Networks (ANN) to describe infiltration, water, and solute distribution in the soil during irrigation. It provides a method of simulating water and solute movement in the subsurface which, in principle, is different and has some advantages over the more common approach of numerical modeling of flow and transport equations. The five objectives were (i) Numerically develop a database for the prediction of water and solute distribution for irrigation; (ii) Develop predictive models using ANN; (iii) Develop an experimental (laboratory) database of water distribution with time; within a transparent flow cell by high resolution CCD video camera; (iv) Conduct field studies to provide basic data for developing and testing the ANN; and (v) Investigate the inclusion of water quality [salinity and organic matter (OM)] in an ANN model used for predicting infiltration and subsurface water distribution. A major accomplishment was the successful use of Moment Analysis (MA) to characterize “plumes of water” applied by various types of irrigation (including drip and gravity sources). The general idea is to describe the subsurface water patterns statistically in terms of only a few (often 3) parameters which can then be predicted by the ANN. It was shown that ellipses (in two dimensions) or ellipsoids (in three dimensions) can be depicted about the center of the plume. Any fraction of water added can be related to a ‘‘probability’’ curve relating the size of the ellipse (or ellipsoid) that contains that amount of water. The initial test of an ANN to predict the moments (and hence the water plume) was with numerically generated data for infiltration from surface and subsurface drip line and point sources in three contrasting soils. The underlying dataset consisted of 1,684,500 vectors (5 soils×5 discharge rates×3 initial conditions×1,123 nodes×20 print times) where each vector had eleven elements consisting of initial water content, hydraulic properties of the soil, flow rate, time and space coordinates. The output is an estimate of subsurface water distribution for essentially any soil property, initial condition or flow rate from a drip source. Following the formal development of the ANN, we have prepared a “user-friendly” version in a spreadsheet environment (in “Excel”). The input data are selected from appropriate values and the output is instantaneous resulting in a picture of the resulting water plume. The MA has also proven valuable, on its own merit, in the description of the flow in soil under laboratory conditions for both wettable and repellant soils. This includes non-Darcian flow examples and redistribution and well as infiltration. Field experiments were conducted in different agricultural fields and various water qualities in Israel. The obtained results will be the basis for the further ANN models development. Regions of high repellence were identified primarily under the canopy of various orchard crops, including citrus and persimmons. Also, increasing OM in the applied water lead to greater repellency. Major scientific implications are that the ANN offers an alternative to conventional flow and transport modeling and that MA is a powerful technique for describing the subsurface water distributions for normal (wettable) and repellant soil. Implications of the field measurements point to the special role of OM in affecting wettability, both from the irrigation water and from soil accumulation below canopies. Implications for agriculture are that a modified approach for drip system design should be adopted for open area crops and orchards, and taking into account the OM components both in the soil and in the applied waters.