Artykuły w czasopismach: „CFD numerical simulation”

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Zhang, Xinfang, Miao Li, Bomin Wang i Zexian Li. "A Parameter Correction method of CFD based on the Approximate Bayesian Computation technique". Journal of Physics: Conference Series 2569, nr 1 (1.08.2023): 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.

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Ohsaki, Shuji, Ryosuke Mitani, Saki Fujiwara, Hideya Nakamura i 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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Ohsaki, Shuji, Ryosuke Mitani, Saki Fujiwara, Hideya Nakamura i 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., i M. I. Gheres. "Numerical evaluation of vehicles aerodynamics in platoon using CFD simulation". IOP Conference Series: Materials Science and Engineering 1220, nr 1 (1.01.2022): 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.

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Laín-Beatove, Santiago, Manuel J. García.Ruiz, Brian Quintero-Arboleda i Santiago Orrego-Bustamante. "CFD Numerical simulations of Francis turbines". Revista Facultad de Ingeniería Universidad de Antioquia, nr 51 (20.03.2013): 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.

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Shi, Xueqing, Daniel (Jian) Sun, Ying Zhang, Jing Xiong i 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, nr 12 (24.06.2020): 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.

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Lenhard, Richard, Katarína Kaduchová i Jozef Jandačka. "Numerical Simulation of Indirectly Heated Hot Water Heater". Advanced Materials Research 875-877 (luty 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.

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Grecu, I. S., G. Dunca, D. M. Bucur i M. J. Cervantes. "URANS numerical simulations of pulsating flows considering streamwise pressure gradient on asymmetric diffuser". IOP Conference Series: Earth and Environmental Science 1079, nr 1 (1.09.2022): 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.

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Shaheed, Aya kh, i Riyadh Z. Azzubaidi. "CFD Simulation Model of Salt Wedge Propagation". Journal of Engineering 28, nr 1 (1.01.2022): 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.

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Sandham, N. D., M. Alam i S. Morin. "Embedded direct numerical simulation for aeronautical CFD". Aeronautical Journal 105, nr 1046 (kwiecień 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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Scurtu, Ionut Cristian, i Valeriu Nicolae Panaitescu. "Turbulent Flow Numerical Simulation for Unconventional Propulsion". Revista de Chimie 70, nr 10 (15.11.2019): 3508–11. http://dx.doi.org/10.37358/rc.19.10.7585.

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This paper presents mainly a new HPC/CFD numerical simulation for airflow around the rigid sail for Lupo90 boat in Constanta harbor conditions. The first part of the work displays the performed numerical simulation in turbulent flow based on the 3D sail. The presented model has high capacity of towing and it can be installed onboard existing ships. This is the result of the HPC (high performance computing) and CFD (computational fluid dynamics) which is a mixture of actual hardware and software at high level computing power applied to Lupo90 boat. All data for rigid sail is analyzed in a turbulent flow in commercial fluid dynamics ANSYS module CFX available at Naval Academy and the work was supported by Romanian Ministry of Defense. Sail performance studying in turbulent flow for the rigid sail onboard ships was always a huge computational difficulty and the HPC/CFD analysis available can solve tricky tasks. The most common unconventional systems are hybrid propulsion systems are using fossil fuel and wind energy, this type of HPC/CFD method for propulsion investigation is now implemented by craft constructor CirusPlast SRL.

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Huang, Ling, i Xia Bing Liu. "Numerical Simulation Research about Group High-Rise Buildings around Wind Environment". Advanced Materials Research 446-449 (styczeń 2012): 657–60. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.657.

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Using the common classical turbulence model, k-ε turbulence model which has fairly common usability，CFD simulations for group high-rise building and wind-induced static interference between tall buildings, are conducted. Based on the comparison between the CFD and relative wind tunnel test ,it shows that: the method of numerical simulation have better accuracy, could be used for group high-rise buildings study of static interference.

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Mikjaniec, T., P. Blais i J. Parry. "Numerical Basis and Validation of CAD-Centric CFD: Honeycomb Heatsink Study". NAFEMS International Journal of CFD Case Studies 11 (kwiecień 2016): 75–89. http://dx.doi.org/10.59972/0gtq77z4.

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In a study by Ma et al. (2010), an innovative honeycomb heatsink design for an LED lighting system was analysed using computational fluid dynamics (CFD) and experimentation. The previous simulation results were replicated using an immersed boundary approach, validating the code against that used in the earlier study. When we looked critically at the images of the experiment in Ma et al. (2010), we noted some discrepancies between the simulation model and the experimental setup. Although the experimental setup was not fully described, we were able to identify a number of issues and make near-exact estimates of the dimensions and other values needed to include their effects in the simulation. The resulting simulation matched the test data very well. In this paper, we present the rationale for applying a different approach that is commonly used in electronics thermal design. We also describe the different aspects of the alternative CFD technology used, as these will not be familiar to most readers, to describe how it can handle fluid flow and heat transfer within complex geometries without simplification. These benefits are illustrated using the honeycomb heatsink example.

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AYUB, ALIATULNAJIHA, i MOHD ASAMUDIN A RAHMAN. "NUMERICAL SIMULATION ON A DEEP-DRAFT SEMI-SUBMERSIBLE". Universiti Malaysia Terengganu Journal of Undergraduate Research 3, nr 2 (30.04.2021): 77–88. http://dx.doi.org/10.46754/umtjur.v3i2.207.

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A numerical study is conducted to determine the Vortex Induced Motion (VIM) effects on Deep-Draft Semi-Submersibles (DDSS). The VIM phenomena is a crucial problem that can cause severe impact on the fatigue life of mooring risers in DDSS. Therefore, a comprehensive numerical simulation is conducted using the Acusolve computational fluid dynamics (CFD) software. Five models of immersed columns with different aspect ratios (ie. 0.6, 0.8, 1.0, 1.2 and 1.4) are numerically investigated under two different incidence angles, which are 0° and 45°. The transverse and in-line vibration amplitude, amplitude of lift force coefficient and vortex shedding are analyzed. The numerical measurements are obtained to see the response of horizontal plane motions, which are transverse, in line and yaw motions. This study with detailed numerical results from parametric data will contribute future studies and the comparisons are made to demonstrate the capability of the present CFD approach.

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Hao, Dan Dan, Wen Sheng Liu, Le Ping Dang i Hong Yuan Wei. "Numerical Simulation of a Coke Oven". Advanced Materials Research 479-481 (luty 2012): 586–89. http://dx.doi.org/10.4028/www.scientific.net/amr.479-481.586.

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At present, the CFD numerical simulation, combined with an experiments involving heat transfer has become an important approach to studying coal carbonization. The aim of this paper is to illustrate how a standard CFD package may be modiﬁed so it can be used to simulate temperature distribution, coking time and carbonization processes that occur in coke oven charge. Content of volatile matters and moisture have important influence on heating rate during carbonization. Further, heating rate have effects on char structure an inner coking condition, as well as the carbonization time. In addition, furnace wall temperature have important effects on carbonization, because they can change the coking time. Our simulation results for the coke oven model are in agreement with experimental and virtual data.

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Chen, Jie, i Miao Hua Huang. "Automobile Modeling Research Based on Numerical Simulation". Applied Mechanics and Materials 733 (luty 2015): 587–90. http://dx.doi.org/10.4028/www.scientific.net/amm.733.587.

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In order to adapt to new modern car styling, the aerodynamic numerical simulations based on computational fluid dynamics (CFD) are applied to the process of car styling. We received the early modeling design automobile aerodynamic coefficients, pressure distribution, velocity contours and other body outflow field data after the CFD post, combined with these data some advice to improve the aerodynamic drag of the designed car are given. Proposed aerodynamic automobile design method is based on numerical simulations, according to experience in air vehicle dynamics studies.

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Ribeiro, J. A., A. S. Reis, P. S. Avendaño, C. H. Ataíde i Marcos A. S. Barrozo. "Experimental and CFD Simulation of a Bubble Column". Materials Science Forum 727-728 (sierpień 2012): 1824–29. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1824.

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The numerical simulation in fluid mechanics has large application in chemical engineering. The objective of the present work is the analyze of a computational model for the fluid dynamics behaviour of a bubble column of the geometry cylindrical non regular with multiphase mixture. Experimental data and CFD results of the hydrodynamics of gaseous and liquid phases have been compared. Five different diameters of bubbles have been used in the CFD simulations. The comparisons between CFD simulations and experimental data show that the Eulerian-Eulerian approach provides a computational model that represents the process satisfactorily.

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Zelenský, Petr, Martin Barták, Vojtìch Zavøel, Vladimír Zmrhal i Radislav Krupa. "Numerical Analysis of Air Flow in a Modular Fan Unit Using CFD Simulation". E3S Web of Conferences 111 (2019): 01008. http://dx.doi.org/10.1051/e3sconf/201911101008.

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The current regulation of European Commission No. 1253/2014 regarding Ecodesing requirements for ventilation units, which classified them based on the Specific Fan Power (SFP), has been driving the innovation in the sector of air-handling systems. The required energy saving can be met by applying modern and energy efficient Electronically Commutated (EC) motor which, at the same time, significantly change the internal geometry of the fan unit. The paper deals with design of a new type of modular fan unit ALTEKO Alton with EC motor and unhoused backward curved impeller. The design development and optimization of the fan unit leading to the reduction of generated aerodynamic noise, lower pressure loss and better outflow characteristics is supported by the Computational Fluid Dynamic (CFD) simulations, which enables visualization of air streamlines, velocities and pressure contours within the unit. Such a design is an iterative process between CFD specialist and construction team, where, based on the simulated results, the critical spots are identified, the geometry is improved and again verified throughout the CFD simulation. The paper describes in detail the individual steps of the optimization study, starting with the import of the detailed geometry from the design CAD software and its necessary simplification for the use in the CFD study, meshing of the model and consequent simulation. The methods of the fan rotation approximation are discussed as well. Additionally, the optimum position of heat exchanger in front of the fan unit is addressed. The presented work is a part of a project supported by the EU under the Operational Program Enterprise and Innovation for Competitiveness.

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Szpicer, Arkadiusz, Weronika Binkowska, Adrian Stelmasiak, Iwona Wojtasik-Kalinowska, Agnieszka Wierzbicka i Andrzej Poltorak. "Application of computational fluid dynamics simulation in predicting food protein denaturation: numerical studies on selected food products - a review*". Animal Science Papers and Reports 41, nr 4 (1.12.2023): 307–32. http://dx.doi.org/10.2478/aspr-2023-0014.

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Abstract Protein denaturation is a common process in the food industry, which can impact food quality and safety. Computational Fluid Dynamics (CFD) is a powerful tool that can be used to predict protein denaturation in food products. In this review article, we present an overview of the application of CFD simulation in predicting protein denaturation in food products. We discuss the factors that influence protein denaturation, the importance of predicting protein denaturation, and the various numerical methods used in protein denaturation studies. The main focus of the article is the use of CFD simulation in predicting protein denaturation in selected food products, such as milk, meat, and eggs. We provide examples of numerical studies that have been conducted on these products, and we discuss the results and implications of these studies. The use of CFD simulation can help to optimize food processing conditions, improve food quality and safety, and reduce waste and costs in the food industry. Overall, this review article highlights the importance of using advanced computational tools such as CFD simulation in food science, research and development. Highlights The use of CFD simulation can predict protein denaturation in food products. Numerical studies were conducted on selected food products to analyze protein denaturation. CFD simulation provides a powerful tool for optimizing food processing technologies. The results from the numerical studies can be used to improve the quality and safety of food products. The application of CFD simulation can lead to more efficient and sustainable food production practices.

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Gonzales, Howell B., John Tatarko, Mark E. Casada, Ronaldo G. Maghirang, Lawrence J. Hagen i Charles J. Barden. "Computational Fluid Dynamics Simulation of Airflow through Standing Vegetation". Transactions of the ASABE 62, nr 6 (2019): 1713–22. http://dx.doi.org/10.13031/trans.13449.

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Abstract. Maintaining vegetative cover on the soil surface is the most widely used method for control of soil loss by wind erosion. We numerically modeled airflow through artificial standing vegetation (i.e., simulated wheat plants) using computational fluid dynamics (CFD). A solver (simpleFoam within the OpenFOAM software architecture) was used to simulate airflow through various three-dimensional (3D) canopy structures in a wind tunnel, which were created using another open-source CAD geometry software (Salomé ver. 7.2). This study focused on two specific objectives: (1) model airflow through standing vegetation using CFD, and (2) compare the results of a previous wind tunnel study with various artificial vegetation configurations to the results of the CFD model. Wind speeds measured in the wind tunnel experiment differed slightly from the numerical simulation using CFD, especially near positions where simulated vegetation was present. Effective drag coefficients computed using wind profiles did not differ significantly (p <0.05) between the experimental and simulated results. Results of this study will provide information for research into other types of simulated stubble or sparse vegetation during wind erosion events.HighlightsMeasured airflow through a simulated canopy was successfully modeled using CFD software.Effective drag coefficients did not differ between the experimental and simulated results.Results of this study provide 3-D simulation data of wind flow through a plant canopy. Keywords: 3-D canopy structure, OpenFOAM, Wind erosion, Wind tunnel studies.

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Perić, M. "Simulation of Flows in Complex Geometries: New Meshing and Solution Methods". NAFEMS International Journal of CFD Case Studies 6 (marzec 2007): 27–37. http://dx.doi.org/10.59972/utux3hbg.

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The use of CFD is spreading in all areas of engineering. The flow domains are usually very complicated, which places high demands on both meshing and solution methods. In this manuscript the newest developments in the handling of complex geometries in CFD are presented. The limitations with respect to the shape of control volumes that may appear in a numerical grid are lifted: cells of arbitrary polyhedral shape are allowed. CAD-integration of all CFD tools and automatic generation of polyhedral meshes, as well as a solution method that can use such meshes, are also presented and the advantages of the new technology are discussed. The emphasis is on CAD integration, automatic mesh generation, and optimisation of mesh quality. The aim of all of these measures is the shortening of analysis time in all phases of a CFD simulation and at the same time an improvement of solution quality.

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Velísková, Yvetta, Zdeněk Chára, Radoslav Schügerl i Renáta Dulovičová. "CFD simulation of flow behind overflooded obstacle". Journal of Hydrology and Hydromechanics 66, nr 4 (1.12.2018): 448–56. http://dx.doi.org/10.2478/johh-2018-0028.

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Abstract This paper deals with studying of two topics – measuring of velocity profile deformation behind a over-flooded construction and modelling of this velocity profile deformation by computational fluid dynamics (CFD). Numerical simulations with an unsteady RANS models - Standard k-ε, Realizable k-ε, Standard k-ω and Reynolds stress models (ANSYS Fluent v.18) and experimental measurements in a laboratory flume (using ADV) were performed. Results of both approaches showed and affirmed presence of velocity profile deformation behind the obstacle, but some discrepancies between the measured and simulated values were also observed. With increasing distance from the obstacle, the differences between the simulation and the measured data increase and the results of the numerical models are no longer usable.

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BLEJCHAR, TOMAS, SYLVA DRABKOVA i VACLAV JANUS. "NUMERICAL MODELLING OF OSCILLATING FLOW FOR ENERGY HARVESTING". MM Science Journal 2021, nr 6 (15.12.2021): 5360–65. http://dx.doi.org/10.17973/mmsj.2021_12_2021102.

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The energy efficiency of systems, equipment, and sensors is nowadays intensively studied. The new generation of microelectronic sensors is very sophisticated and the energy consumption is in the microwatts range. The energy to power the microelectronic devices can be harvested from oscillating flow in small size channels and so replaceable batteries could be eliminated. Piezoelectric elements can convert energy from oscillation to electrical energy. This paper focuses on the simulation of periodic flow in the fluidic oscillator. CFD simulations were performed for several values of the flow rate. Experimental measurement was carried out under the same conditions as the CFD experiment. The main monitored and evaluated parameters were volume flow rate and pressure loss. Fluid oscillations were analysed based on CFD simulations and the theoretical maximum energy available for the deformation of piezoelectric elements and transformable into electrical energy was evaluated.

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Stan, Liviu Constantin, Alexandra Nicoleta Gordes i Adriana Georgiana Agape. "NUMERICAL SIMULATION OF A GEAR". International Journal of Modern Manufacturing Technologies 15, nr 1 (20.06.2023): 107–14. http://dx.doi.org/10.54684/ijmmt.2023.15.1.107.

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To navigate safely, the ship must be manoeuvrable and have good stability. The steering of the ship depends on a number of factors such as: the means of steering used, the geometric shapes of the hull (stern area), the ratios between the main dimensions (LCWL/B and B/T), the number, position and direction of rotation of the engine. and the hydro-meteorological conditions in which they sail (water, air, wind, waves). Every ship, with the exception of barges, must have a robust and safe steering system to ensure manoeuvrability and sea stability. These installations can be: rudder with hydrodynamic profile, installation with adjustable nozzles and other installations approved by the Classification Societies. In this particular study an analysis on a gear pump fitted in the azimuth system of a chemical tanker is being made, using a CFD technology. The main aim is to study the efficiency of this pump by comparing the CFD analysis results with the results in real operational condition. Main parameters focused on are outlet flow, suction column, power and pump efficiency. There are several differences registered in the case of suction column and power, but they are not that high, while parameters outlet flow and pump efficiency are almost identical.

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Fernández-García, María S., Pablo Vidal-López, Desirée Rodríguez-Robles, José R. Villar-García i Rafael Agujetas. "Numerical Simulation of Multi-Span Greenhouse Structures". Agriculture 10, nr 11 (25.10.2020): 499. http://dx.doi.org/10.3390/agriculture10110499.

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Greenhouses had to be designed to sustain permanent maintenance and crop loads as well as the site-specific climatic conditions, with wind being the most damaging. However, both the structure and foundation are regularly empirically calculated, which could lead to structural inadequacies or cost ineffectiveness. Thus, in this paper, the structural assessment of a multi-tunnel greenhouse was carried out. Firstly, wind loads were assessed through computational fluid dynamics (CFD). Then, the buckling failure mode when either the European Standard (EN) or the CFD wind loads were contemplated was assessed by a finite element method (FEM). Conversely to the EN 13031-1, CFD wind loads generated a suction in the 0–55° region of the first tunnel and a 60% reduction of the external pressure coefficients in the third tunnel was not detected. Moreover, the first-order buckling eigenvalues were reduced (32–57%), which resulted in the need for a different calculation method (i.e., elastoplastic analysis), and global buckling modes similar to local buckling shape were detected. Finally, the foundation was studied by the FEM and a matrix method based on the Wrinkler model. The stresses and deformations arising from the proposed matrix method were conservative compared to those obtained by the FEM.

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Yang, Qin, Xian Zhou Wang, Ming Yue Liu, Jing Hu i Zhi Guo Zhang. "Optimization of Valve Block Shape Using CFD". Applied Mechanics and Materials 190-191 (lipiec 2012): 133–38. http://dx.doi.org/10.4028/www.scientific.net/amm.190-191.133.

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Stop valves are commonly used as fluid flow control equipments in many engineering applications. A numerical study of a three-dimensional, complex geometry, stop-check valve was performed for model validation and improved understanding of valve flow features. This paper has provided a numerical investigation of the fluid flow inside a stop valve, including the modeling and the simulation of the stop valves. According to the simulation result of original valve structure, two cone valve block shape with different gradient are presented to bring some optimization to the stop-valve. CFD simulations were conducted for different structure of the valve to verify the performance of the valve after redesign the internal flow structure. The simulation results show that the pressure drop vortex strength, maximum velocity and velocity nonuniformity of valve outlet had been reduced obviously. Furthermore, the results of the three-dimensional optimization analysis of valve shape can be used in the design of low noise and high efficiency valve for industry.

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Jia, Bin, Jianping Jing, Xuedong Qiao i Chunming Zhang. "Numerical Simulation of PRHR System Based on CFD". Journal of Applied Mathematics and Physics 01, nr 06 (2013): 74–81. http://dx.doi.org/10.4236/jamp.2013.16015.

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Zhang, L., L. Wei, B. H. Chang, J. L. Xing i K. Jia. "CFD numerical simulation of Archimedes spiral inlet hydrocyclone". IOP Conference Series: Materials Science and Engineering 52, nr 7 (20.12.2013): 072021. http://dx.doi.org/10.1088/1757-899x/52/7/072021.

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Bruce, R., J. Reynaud, S. Pascali i B. Baudouy. "3D CFD Transient Numerical Simulation of Superfluid Helium". IOP Conference Series: Materials Science and Engineering 278 (grudzień 2017): 012057. http://dx.doi.org/10.1088/1757-899x/278/1/012057.

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Qiao, Geng, Tao Zhang i George N. Barakos. "Numerical simulation of distributed propulsion systems using CFD". Aerospace Science and Technology 147 (kwiecień 2024): 109011. http://dx.doi.org/10.1016/j.ast.2024.109011.

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Mørch, H., M. Perić, J. Röper i E. Schreck. "CFD-Supported Design of Lifeboats". NAFEMS International Journal of CFD Case Studies 10 (marzec 2013): 31–42. http://dx.doi.org/10.59972/ffm3fczg.

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Lifeboats are important for the safety of crew on oil platforms and marine vessels. Their design has so far been mostly based on experimental studies. However, the large number of factors which influence the loads on the lifeboat structure and its occupants makes optimization studies by experimental means both time-consuming and expensive. Besides, many effects cannot be studied at laboratory scale due to the inability to match all similarity parameters, and certain conditions cannot be realized in a laboratory. Numerical simulations based on modern computational fluid dynamics (CFD) methods could complement experimental studies if proven to be sufficiently accurate and efficient. The aim of this study is to demonstrate that this indeed is the case: comparisons between experimental data and simulation results performed by the authors so far indicate that the achieved accuracy in numerical simulations is comparable to the accuracy of experiments. It is also shown that a simulation of one drop test can be performed with sufficient accuracy in one day on a single core of a personal computer. Together with a computational method which uses overlapping grids to simplify the handling of lifeboat motion and specification of initial and boundary conditions, parametric studies of lifeboat water entry have thus become practicable.

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Yun-ya, Liu, Yu-chen Yang i Ya-wen Yang. "Simulation of vertical tidal turbine based on OpenFOAM and influence of inlet turbulence". MATEC Web of Conferences 272 (2019): 01017. http://dx.doi.org/10.1051/matecconf/201927201017.

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This paper first introduces the basic theory of CFD method, including basic control equations, finite volume method, control equation solving algorithm and turbulence model selection. Second, based on OpenFOAM, an open-source fluid mechanics software, a numerical simulation method of vertical axis tidal turbine was proposed by using k-ω SST turbulence model and PIMPLE algorithm. The hydrodynamic characteristics of the vertical axis turbine were studied, and the calculation results were compared with experiments. The higher consistency proves the feasibility of the numerical simulation method proposed in this paper. Finally, the influence of inlet turbulence on numerical simulation was explored, and a set of effective CFD simulation strategies was concluded, which provided a valuable reference for future CFD simulation and research on vertical axis tidal turbines.

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Chen, Ming Zhou, i Qi Dou Zhou. "Numerical Simulation of Fluctuating Propeller Forces and Comparison with Experimental Data". Applied Mechanics and Materials 105-107 (wrzesień 2011): 518–22. http://dx.doi.org/10.4028/www.scientific.net/amm.105-107.518.

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Unsteady CFD method based on realizable k-ε model is used for predicting unsteady forces of propeller working in non-uniform wake. First, CFD computations with different mesh scales were conducted at the propeller design condition, the results show that mesh refinement changed the results little. Then unsteady CFD simulation with different time step intervals was conducted for determining suitable time step interval, the results show that it is suitable for propeller rotating 3° per step. Based on the chosen mesh and time step interval, unsteady CFD simulation of propeller P4118 was conducted in 3-cycle and 4-cycle inflow, the unsteady thrust, torque and horizontal force agree well with experimental data, the results show that CFD method has good accuracy in predicting unsteady propeller forces.

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Choi, Sooseok. "Numerical Simulation of Thermal Plasma Gasification Process". Applied Mechanics and Materials 799-800 (październik 2015): 90–94. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.90.

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Numerical analysis of plasma gasification process was carried out base on the combination of magnetohydrodynamics (MHD) and computational fluid dynamics (CFD). A two stage gasification system which consists of a heater and a plasma rector was used to enhance syngas production in the present work. Nitrogen thermal plasma jet generated by a low power plasma torch was analyzed by a self-developed MHD code, and complex thermal flow field in the plasma reactor was simulated with a commercial CFD code. The accuracy of numerical simulation was confirmed from the comparison between numerical results and experimentally measured data of arc voltage and reactor temperature. From the numerical analysis, a high temperature for the thermal cracking of methane was expected in the upper region of the plasma reactor.

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Yu, Songli, Huichao Dai, Yanwei Zhai, Mengyang Liu i Wenxin Huai. "A Comparative Study on 2D CFD Simulation of Flow Structure in an Open Channel with an Emerged Vegetation Patch Based on Different RANS Turbulence Models". Water 14, nr 18 (15.09.2022): 2873. http://dx.doi.org/10.3390/w14182873.

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Aquatic plants widely exist in rivers, which can affect the flow structure in rivers and have an important impact on the evolution of river morphology. The emerged vegetation is an important member of aquatic vegetation in the river, so studying the flow structure around the emerged vegetation patches is of great significance. Computational fluid dynamics (CFD) simulation provides support for the related research works. Applying the appropriate turbulence model is crucial to achieving realistic numerical simulation results. In this study, two-dimensional numerical simulations were carried out and compared with experimental data by six different Reynolds-Averaged Navier–Stokes (RANS) turbulence models, i.e., Standard k-ε model, Renormalization group (RNG) k-ε model, Realizable k-ε model, Standard k-ω model, Shear-stress transport (SST) k-ω Model, and the Reynolds stress model (RSM). CFD is an effective research method, and the results showed that there are different simulation performances with different turbulence models. The shear stress transport k-ω model achieves the most consistent numerical simulation results with the experimental data for the longitudinal mean flow velocity distribution at the centerline, and the Reynolds stress model provides the least consistent numerical simulation with the experimental data. Then the performance of the six models in simulating the flow field characteristics and longitudinal outflow after vegetation patch was compared.

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Thiedeitz, Mareike, Thomas Kränkel, Deniz Kartal i Jithender J. Timothy. "The Slump Flow of Cementitious Pastes: Simulation vs. Experiments". Materials 17, nr 2 (22.01.2024): 532. http://dx.doi.org/10.3390/ma17020532.

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Understanding the transient properties of cementitious pastes is crucial for construction materials engineering. Computational modeling, particularly through Computational Fluid Dynamics (CFD), offers a promising avenue to enhance our understanding of these properties. However, there are several numerical uncertainties that affect the accuracy of the simulations using CFD. This study focuses on evaluating the accuracy of CFD simulations in replicating slump flow tests for cementitious pastes by determining the impact of the numerical setup on the simulation accuracy and evaluates the transient, viscosity-dependent flows for different viscous pastes. Rheological input parameters were sourced from rheometric tests and Herschel–Bulkley regression of flow curves. We assessed spatial and temporal convergence and compared two regularization methods for the rheological model. Our findings reveal that temporal and spatial refinements significantly affected the final test results. Adjustments in simulation setups effectively reduced computational errors to less than four percent compared to experimental outcomes. The Papanastasiou regularization was found to be more accurate than the bi-viscosity model. Employing a slice geometry, rather than a full three-dimensional cone mesh, led to accurate results with decreased computational costs. The analysis of transient flow properties revealed the effect of the paste viscosity on the time- and shear-dependent flow progress. The study provides an enhanced understanding of transient flow patterns in cementitious pastes and presents a refined CFD model for simulating slump flow tests. These advancements contribute to improving the accuracy and efficiency of computational analyses in the field of cement and concrete flow, offering a benchmark for prospective analysis of transient flow cases.

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Zhao, Zhenjiang, Ling Zhou, Ling Bai, Mahmoud A. El-Emam i Ramesh Agarwal. "Modeling and validation of coarse-grained computational fluid dynamics–discrete element method for dense gas–solid flow simulation in a bubbling fluidized bed". Physics of Fluids 35, nr 4 (kwiecień 2023): 043310. http://dx.doi.org/10.1063/5.0146264.

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Computational fluid dynamics (CFD) combined with the discrete element method (DEM) are powerful tools for analyzing dense gas–solid flows. However, the computational cost of CFD–DEM will be unfeasibly great when simulating large-scale engineering applications with billions of particles. Accordingly, the coarse-grained (CG) CFD–DEM method is applied to solve this problem. This investigated method replaces several smaller particles with larger ones called parcels, aiming to reduce the number of particles and fully consider the collision of particles between composition parcels and the collision of particles within composition parcels. First, high-speed photography verifies the numerical simulation's reliability. Then, the CG CFD–DEM was used to analyze the transient spatial distribution, transient average velocity, pressure drop, bed height, and the mixing state of particles in a dense gas–solid fluidized bed. The CG CFD–DEM was also compared with the CFD–DEM results, which showed a good agreement with the calculation results and proved the accuracy and applicability of the method. Finally, the computation time of the CG CFD–DEM was evaluated, showing a significant decrease in computation time with an increasing coarse ratio ( k). This investigation can provide theoretical reference for the numerical simulation of the CG CFD–DEM method in dense gas–solid flow.

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Bu, Yunchen, Ryozo Ooka, Hideki Kikumoto i Wonseok Oh. "Numerical analysis on temporal size change of expiratory droplets by considering component variation". E3S Web of Conferences 356 (2022): 04015. http://dx.doi.org/10.1051/e3sconf/202235604015.

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When conducting computational fluid dynamics (CFD) simulations to investigate the evaporation characteristics of respiratory particles, the over-simplification of droplet compositions may cause inaccuracies in the results. Although some researchers have conducted parametric studies on droplet components, an investigation using CFD simulation is still lacking. Therefore, this study aimed to determine the effect of different components on the temporal size change of expiratory droplets using CFD simulation. Two droplet sizes (10 μm and 100 μm) were selected, and two types of component combinations were considered, both with a volume fraction of 98.2% for water and 1.8% for non-volatile parts. In Scenario 1, the non-volatile part is composed of NaCl (density: 2200 kg/m3, molecular weight: 58.5 kg/kmol), whereas in Scenario 2, the non-volatile part is composed of NaCl, KCl, lactate, and protein (density: 1000 kg/m3, average molecular weight: 293 kg/kmol). Computations were conducted under constant temperature (25 °C) and different relative humidity (0 and 90%). The results showed that the equilibrium size and equilibrium time were strongly dependent on the droplet components. In subsequent investigations, the effects of different droplet components should be considered in the CFD simulations to obtain more accurate results.

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Młynarczyk, Przemysław. "The influence of the numerical solver selection on the nozzle impulse flow simulation results". MATEC Web of Conferences 240 (2018): 03008. http://dx.doi.org/10.1051/matecconf/201824003008.

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Numerical simulations are currently used for different applications in a various fields of science. Certain solutions are not as obvious as the others while the results can give very valuable conclusions. Computational Fluid Dynamics (CFD) is one of the tools that can be used to solve different problems related with the mass and heat transfer. Nowadays it is already known that the impulse flow simulation allows to determine pressure pulsation attenuation parameters by a given geometry. However, the nozzle shape optimization method strongly depends on the numerical results obtained from the impulse flow simulation. In commercial CFD software Ansys-Fluent the obtained results depends strongly on the chosen numerical methods, especially the spatial discretization method. This is the reason to use other software as a benchmark. Alternative software FlowVision was used to perform the impulse flow simulation for the same geometries to compare the results. As there is a different problem definition in both systems the calculations, accuracy and results differ from each other. The paper describes the numerical differences between solvers. Article contains discussion about obtained results and includes hints how to avoid mistakes when user change software, especially in solving unusual CFD problems.

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Ha, Yoon-Jin, Ji-Yong Park i Seung-Ho Shin. "Numerical Study of Non-Linear Dynamic Behavior of an Asymmetric Rotor for Wave Energy Converter in Regular Waves". Processes 9, nr 8 (23.08.2021): 1477. http://dx.doi.org/10.3390/pr9081477.

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This study conducted a numerical investigation on the non-linear motion problems between a Salter duck-type rotor and large waves using CFD simulations. Regular waves of five different wave heights were generated. First, the linear motion of the rotor from the CFD simulation was verified by comparing it with the existing experimental and frequency domain analysis results. Then, a series of CFD simulations were performed to investigate the non-linear motions of the rotor. In the case of a lower wave height, the CFD simulation results were in good agreement with the experimental and frequency domain analysis results. However, as the wave height increased, the resonance periods were different in each other. In addition, the magnitudes of normalized pitch motions by the wave heights decreased as the wave heights increased. To investigate the aforementioned phenomena, the pitch motion equation was examined using separate CFD simulations. The results showed that changing the restoring moments induced changes in the maximum pitch motions and magnitudes of the normalized pitch motions. In the case of a higher wave height, non-linear phenomena and the changing restoring moments induced non-linear motion.

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Hodapp, Maximilian J., Jhon J. Ramirez-Behainne, Milton Mori i Leonardo Goldstein. "Numerical Studies of the Gas-Solid Hydrodynamics at High Temperature in the Riser of a Bench-Scale Circulating Fluidized Bed". International Journal of Chemical Engineering 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/786982.

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The hydrodynamics of circulating fluidized beds (CFBs) is a complex phenomenon that can drastically vary depending on operational setup and geometrical configuration. A research of the literature shows that studies for the prediction of key variables in CFB systems operating at high temperature still need to be implemented aiming at applications in energy conversion, such as combustion, gasification, or fast pyrolysis of solid fuels. In this work the computational fluid dynamics (CFD) technique was used for modeling and simulation of the hydrodynamics of a preheating gas-solid flow in a cylindrical bed section. For the CFD simulations, the two-fluid approach was used to represent the gas-solid flow with the k-epsilon turbulence model being applied for the gas phase and the kinetic theory of granular flow (KTGF) for the properties of the dispersed phase. The information obtained from a semiempirical model was used to implement the initial condition of the simulation. The CFD results were in accordance with experimental data obtained from a bench-scale CFB system and from predictions of the semiempirical model. The initial condition applied in this work was shown to be a viable alternative to a more common constant solid mass flux boundary condition.

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Liu, Yitao. "Systematic computational methods of unsteady flow simulation based on computational fluid dynamics". Applied and Computational Engineering 12, nr 1 (25.09.2023): 151–63. http://dx.doi.org/10.54254/2755-2721/12/20230328.

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Unsteady flow is the dominant flow state in real life; thus, the simulation of it is of vital importance, especially in engineering, for example, the flutter or buffeting of the aerofoil. In the past decades, the progress in computational science greatly paced the development of computational fluid dynamics (CFD), providing powerful tools for simulating unsteady flow via numerical methods. However, the unsteady flow state depends on more variables than a steady flow, including the external conditions in different time moments and the flow's properties that vary with time. The calculation is still too massive, even using CFD. Therefore, CFD algorithms with higher efficiency and less reduction in accuracy are still needed to optimize the technique. This paper reviews the main CFD computational methods that have been maturely developed and proven effective, including direct numerical simulation (DNS), classic turbulence models and reduced order model (ROM), illustrating the main mechanisms and displaying their features. The paper also sheds light on these methods' latest research progress.

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Jiang, Neng Jun, Ya Ling Peng i Fang Liang Wu. "Improve Journal Bearing Design Using Numerical Method". Applied Mechanics and Materials 99-100 (wrzesień 2011): 857–61. http://dx.doi.org/10.4028/www.scientific.net/amm.99-100.857.

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Computational Fluid Dynamics (CFD) was used to study the force direction and magnitude of 2D journal bearing and tapered gap, also the load of 3D journal bearing at different eccentric ratio was studied using numerical method. All numerical simulation results were compared with theoretical analysis result, theoretical solution result and other available data from reference. The comparisons show good match between numerical simulation results and others. This paper had validated the reliability and accuracy of CFD which could be used to study the lubrication and oil film status for journal bearing with the gap less than 0.2mm and provide a sold foundation for CFD to be used for optimal design for journal bearing.

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Szűcs, Herman. "Reconstruction of 3D Porous Geometry for Coupled FEM-CFD Simulation". Periodica Polytechnica Mechanical Engineering 66, nr 2 (22.03.2022): 129–36. http://dx.doi.org/10.3311/ppme.19438.

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Porous materials can be found in numerous areas of life (e. g., applied science, material science), however, the simulation of the fluid flow and transport phenomena through porous media is a significant challenge nowadays. Numerical simulations can help to analyze and understand physical processes and different phenomena in the porous structure, as well as to determine certain parameters that are difficult or impossible to measure directly or can only be determined by expensive and time-consuming experiments. The basic condition for the numerical simulations is the 3D geometric model of the porous material sample, which is the input parameter of the simulation. For this reason, geometry reconstruction is highly critical for pore-scale analysis. This paper introduces a complex process for the preparation of the microstructure's geometry in connection with a coupled FEM-CFD two-way fluid-structure interaction simulation. Micro-CT has been successfully applied to reconstruct both the fluid and solid phases of the used porous material.

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De Andrade, Jesús, Christian Curiel, Frank Kenyery, Orlando Aguillón, Auristela Vásquez i Miguel Asuaje. "Numerical Investigation of the Internal Flow in a Banki Turbine". International Journal of Rotating Machinery 2011 (2011): 1–12. http://dx.doi.org/10.1155/2011/841214.

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The paper refers to the numerical analysis of the internal flow in a hydraulic cross-flow turbine type Banki. A 3D-CFD steady state flow simulation has been performed using ANSYS CFX codes. The simulation includes nozzle, runner, shaft, and casing. The turbine has a specific speed of 63 (metric units), an outside runner diameter of 294 mm. Simulations were carried out using a water-air free surface model and k-εturbulence model. The objectives of this study were to analyze the velocity and pressure fields of the cross-flow within the runner and to characterize its performance for different runner speeds. Absolute flow velocity angles are obtained at runner entrance for simulations with and without the runner. Flow recirculation in the runner interblade passages and shocks of the internal cross-flow cause considerable hydraulic losses by which the efficiency of the turbine decreases significantly. The CFD simulations results were compared with experimental data and were consistent with global performance parameters.

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Čížek, Michal, Vojtěch Klír, Pavel Steinbauer i Tomáš Vampola. "LABYRINTH SEAL CFD CALCULATION AND TEMPERATURE MEASUREMENT INVESTIGATION". Aviation 26, nr 2 (1.06.2022): 96–103. http://dx.doi.org/10.3846/aviation.2022.16886.

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This article presents currently obtained results from CFD analysis of the labyrinth seals of an aircraft turbine engine. The process of describing a geometry, grid for numerical calculation and boundary conditions are described. Numerical simulations were performed for the assumed boundary conditions. The presented results show total temperature differences in labyrinth seals compared to published results. An experimental verification of the CFD analysis was also performed to clarify the numerical simulation results. It was based on the labyrinth seal measurement stand. The final part of this study is dedicated to the discussion and the following possible activities on this topic.

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AbdelGawad, Alaa R., i Liang Guozhu. "A Numerical Simulation Study for A Dual Thrust Solid Propellant Rocket Motor Nozzle". Journal of Physics: Conference Series 2235, nr 1 (1.05.2022): 012010. http://dx.doi.org/10.1088/1742-6596/2235/1/012010.

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Abstract CFD simulation through the rocket motor nozzle is an important issue as it gives a better understanding of the flow behavior and shows the evolution of the parameters along with the nozzle. CFD simulations using ANSYS FLUENT were conducted to model the flow through an experimental dual thrust solid rocket motor nozzle at two pressure values representing the two pressure levels. A two-dimensional axisymmetric numerical simulation was carried out using a pressure-based solver to solve the governing equation and the standard k-ε model to model the turbulence through the motor nozzle. The hot gas properties used in the simulation model were calculated using the CEA software (chemical equilibrium with applications). The parameters marched out from simulations were used to calculate the thrust values for each case. The results calculated through the numerical models compared with the experimental measurements and showed an acceptable level of accuracy.

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Budea, Sanda, i Ion-Bogdan Iordan. "Radial Centrifugal Fan Redesign and New Technologies Using CFD Applications". Technium: Romanian Journal of Applied Sciences and Technology 14 (9.10.2023): 115–19. http://dx.doi.org/10.47577/technium.v14i.9690.

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The purpose of this article is to redesign centrifugal radial fans used in HVAC installations, using the analysis of aerodynamic flows and velocities distributions in the fan. Numerical simulations based on the reference model from the Pumps and Fans laboratory were performed using the SolidWorks program, Flow Simulation module. Following the simulations, information regarding the fluid flow in the machine rotor and casing, the most suitable shape of the blades resulted, and redesign solutions through 3D printing technologies were proposed. Numerical simulations with Flow Simulation on three-dimensional models were carried out, for a better analysis of the volume of air passing through the fan, but also for the prediction of some negative effects: the appearance of vortices that lead to high noises/acoustic disturbances, the appearance of additional vibrations, but also sudden and uncontrolled variations in the pressure force. Following the numerical analysis, it was found that for the new blade profiles the velocities are uniform, which greatly reduces the noise and vibrations in the operation of the fan. The redesign also aims to reduce the energy consumption of these fans.

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Scheibe, Andreas, Engelbert Westkämper i Qiaoyan Ye. "Numerical Simulation of Painting Processes". NAFEMS International Journal of CFD Case Studies 8 (grudzień 2009): 39–50. http://dx.doi.org/10.59972/11x97e6u.

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The present contribution summarises ongoing investigations performed at the Institut für Industrielle Fertigung und Fabrikbetrieb (IFF) on the numerical simulation of spray painting in the automotive industry. Numerical models for electro-statically supported or pneumatic painting processes were implemented in a CFD code. These models account for all important effects involved in the relevant physical processes, being able to predict the film thickness distribution and the paint transfer efficiency on the work piece. Some tests on complicated targets have been carried out. The results confirm the applicability and reliability of the chosen models for the painting processes.

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SCUPI, Andrei-Alexandru, Mariana PANAITESCU i Fanel-Viorel PANAITESCU. "NUMERICAL SIMULATION OF CENTRIFUGAL PUMP". Journal of Marine Technology and Environment, nr 1 (1.04.2023): 50–53. http://dx.doi.org/10.53464/jmte.01.2023.08.

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"Centrifugal pumps are most commonly used pumping devices in industry their being fit for pumping water. There are several types of centrifugal pumps, their differences in construction is due to their size and how cloggy the pumped water is. In the paper it was simulated a 2D centrifugal pump of small size used in daily activities. The simulation, performed with CFD (ANSYS-Fluent), was made for different inlet velocities of water. Different parameters, such as inlet pressure, outlet pressure, maximum velocity and flow rate, were calculated and graphically represented against inlet velocity. Also, graphical representation of pressure distribution ."

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