Bibliographies thématiques / CFD modelling for gas coolers

Sommaire

Articles de revues
Thèses
Livres
Chapitres de livres
Actes de conférences

Littérature scientifique sur le sujet « CFD modelling for gas coolers »

Auteur : Grafiati

Publié le 4 juin 2021

Mis à jour le 17 février 2022

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres

Choisissez une source :

Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « CFD modelling for gas coolers ».

À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.

Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.

Articles de revues sur le sujet "CFD modelling for gas coolers"

Zhang, Xinyu, Yunting Ge, Jining Sun, Liang Li et Savvas A. Tassou. « CFD Modelling of Finned-tube CO2 Gas Cooler for Refrigeration Systems ». Energy Procedia 161 (mars 2019) : 275–82. http://dx.doi.org/10.1016/j.egypro.2019.02.092.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Adeniyi, A. A., H. P. Morvan et K. A. Simmons. « A coupled Euler-Lagrange CFD modelling of droplets-to-film ». Aeronautical Journal 121, n^o 1246 (13 octobre 2017) : 1897–918. http://dx.doi.org/10.1017/aer.2017.107.

Texte intégral

Résumé :

ABSTRACTIn this paper, a droplet to film interaction model technique is presented. In the proposed approach, the liquid and gas continua are modelled using an enhanced Volume-of-Fluid (VoF) technique while the droplets are tracked using a Lagrangian framework and are coupled to the Eulerian phases using source terms. The eventual target application is an aeroengine bearing chamber in which oil is found as droplets, shed from the bearings, splashing on impact, separated from wall surfaces at obstacles or simply re-entrained, and as a continuum oil film coating the bearing chamber outer walls which it also cools. In finite volume Computational Fluid Dynamics (CFD) techniques, a prohibitively large number of cells would be required to describe the details of the droplet impact phenomenon. Based on published correlations, the splashing droplets are created and tracked as Lagrangian particles. The flowing film and the gas continua are handled with an enhanced VoF technique.

Styles APA, Harvard, Vancouver, ISO, etc.

Orosz, Gergely Imre, et Attila Aszódi. « CFD modelling of mixing vane spacer grids for ALLEGRO relevant gas cooled reactor fuel geometry ». Annals of Nuclear Energy 164 (décembre 2021) : 108628. http://dx.doi.org/10.1016/j.anucene.2021.108628.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Javiya, Umesh, John Chew, Nick Hills et Timothy Scanlon. « Coupled FE–CFD thermal analysis for a cooled turbine disk ». Proceedings of the Institution of Mechanical Engineers, Part C : Journal of Mechanical Engineering Science 229, n^o 18 (18 février 2015) : 3417–32. http://dx.doi.org/10.1177/0954406215572430.

Texte intégral

Résumé :

This paper presents transient aero-thermal analysis for a gas turbine disk and the surrounding air flows through a transient slam acceleration/deceleration “square cycle” engine test, and compares predictions with engine measurements. The transient solid–fluid interaction calculations were performed with an innovative coupled finite element (FE) and computational fluid dynamics (CFD) approach. The computer model includes an aero-engine high pressure turbine (HPT) disk, adjacent structure, and the surrounding internal air system cavities. The model was validated through comparison with the engine temperature measurements and is also compared with industry standard standalone FE modelling. Numerical calculations using a 2D FE model with axisymmetric and 3D CFD solutions are presented and compared. Strong coupling between CFD solutions for different air system cavities and the FE solid model led to some numerical difficulties. These were addressed through improvement of the coupling algorithm. Overall performance of the coupled approach is very encouraging giving temperature predictions as good as a traditional model that had been calibrated against engine measurements.

Styles APA, Harvard, Vancouver, ISO, etc.

Zhang, X. Y., Y. T. Ge et J. N. Sun. « Performance analysis of finned-tube CO2 gas cooler with advanced 1D-3D CFD modelling development and simulation ». Applied Thermal Engineering 176 (juillet 2020) : 115421. http://dx.doi.org/10.1016/j.applthermaleng.2020.115421.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Kukutla, Pol, et B. Prasad. « Coupled flow network model and CFD analysis for a combined impingement and film cooled gas turbine nozzle guide vane ». Modelling, Measurement and Control B 86, n^o 1 (30 mars 2017) : 250–70. http://dx.doi.org/10.18280/mmc_b.860118.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Rossetti, Antonio, Sergio Marinetti et Silvia Minetto. « Multi-physics simulation of CO2 gas coolers using equivalence modelling ». International Journal of Refrigeration 90 (juin 2018) : 99–107. http://dx.doi.org/10.1016/j.ijrefrig.2018.04.013.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Al-Rashed, Mohsen H., et Alan G. Jones. « CFD modelling of gas–liquid reactive precipitation ». Chemical Engineering Science 54, n^o 21 (novembre 1999) : 4779–84. http://dx.doi.org/10.1016/s0009-2509(99)00194-3.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Mangra, A. C. « Micro gas turbine combustion chamber CFD modelling ». IOP Conference Series : Materials Science and Engineering 916 (11 septembre 2020) : 012064. http://dx.doi.org/10.1088/1757-899x/916/1/012064.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Zilio, Claudio, et Simone Mancin. « Shell and tube carbon dioxide gas coolers – Experimental results and modelling ». International Journal of Refrigeration 56 (août 2015) : 224–34. http://dx.doi.org/10.1016/j.ijrefrig.2015.04.006.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Plus de sources

Thèses sur le sujet "CFD modelling for gas coolers"

Santosa, I. Dewe. « Optimisation gas coolers for CO2 refrigeration application ». Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/12161.

Texte intégral

Résumé :

Carbon dioxide (CO2) is a natural, low cost refrigerant with good thermo-physical properties. CO2 is a good alternative for replacing HFC refrigerants that possess high global warming potential and reducing the direct impacts of refrigeration systems on the environment. However, CO2 refrigeration systems operate at relatively high condenser/gas cooler pressures and this imposes special design and control considerations. The gas cooler is a very important part of the system and can have significant influence on its performance. In sub-critical operation, good gas cooler/condenser design can reduce the condenser pressure and delay switching to supercritical operation which increases system efficiency. In supercritical operation optimum design and control can enable the system to operate at pressures that maximise system efficiency. In air cooled systems, gas coolers/condensers are of the finned-tube type. This type of heat exchanger is well established in the HVAC and refrigeration industries. The large changes in the CO2 properties in the gas cooler, however, during supercritical operation impose special design and manufacturing considerations. This research project considered the influence of the unique heat transfer characteristics of CO2 on the design and performance of finned tube air cooled condensers/gas coolers for CO2 refrigeration applications. A combined experimental and modelling approach using Computational Fluid Dynamics (CFD) was employed. A CO2 condenser/gas cooler test facility was developed for the experimental investigations. The facility employs a ‘booster’ hot gas bypass CO2 refrigeration system, with associated condenser/gas cooler test rig and evaporator load simulation facility. A series of experimental tests were carried out with two gas coolers which incorporated horizontal and horizontal-vertical slit fins and was obtained adequate experimental data concerning gas cooler performance. CFD modelling was used to study the performance of the gas coolers. The model was validated against test results and was shown to predict the air outlet temperature and heat rejection of the gas cooler with an accuracy of within ±5%. The model was subsequently used to evaluate the effect of a fin slit between the 1st and 2nd row of tubes of the gas cooler as well as a vertical slit on the 1st row before the last tube of the section. The results showed a 6%-8% increase in the heat rejection rate of the gas cooler compared to the performance without the horizontal slit. The vertical slit in the fin of the last tube has resulted in an additional increase in heat rejection over and above that for the horizontal slit of 1%-2%. CFD modelling was also used to investigate the variation of the refrigerant side, air side and overall heat transfer coefficient along the heat exchanger. The results showed that the refrigerant heat transfer coefficient increases with the decreasing of bulk refrigerant temperature and reaches its maximum when the specific heat of the refrigerant is highest. Furthermore, increasing the refrigerant mass flux, increases the refrigerant side heat transfer coefficient and heat rejection. This can reduce the size of the gas cooler for a given capacity at the expense of higher pressure drop and compressor power consumption. Air side and overall heat transfer coefficient correlations were developed for the specific gas cooler designs which were investigated and showed the heat transfer coefficients increase with increasing Reynolds Number.

Styles APA, Harvard, Vancouver, ISO, etc.

Van, Antwerpen Hermanus Johannes. « Modelling a pebble bed high temperature gas-cooled reactor using a system-CFD approach / Hermanus Johannes (Herman) van Antwerpen ». Thesis, North-West University, 2007. http://hdl.handle.net/10394/1301.

Texte intégral

Résumé :

The objective of this study was the development of a systems-CFD model of the PBMR reactor that used the minimum number of grid points to achieve grid independence. The number of grid points is reduced by increasing the accuracy of the discretisation scheme in the reactor model. Any reduction in the number of grid points leads to an increase in calculation speed, which is critical for systems simulation codes that are used for optimisation or transient simulations. While some previous reactor models had been developed for systems simulation codes, their discretisation schemes have not been optimised to use the minimum number of grid points and some heat transfer phenomena were neglected without knowing the effect. Therefore, there was a need to optimise discretisation schemes as well as investigate the effect of including certain heat transfer mechanisms. Modelling methods for several phenomena were developed and implemented in a reactor model in the Flownex systems simulation code, which is used to simulate the PBMR. Subjects of investigation included pebble bed convection discretisation, fuel sphere discretisation, the effect of the radiation heat transfer modelling approach as well as conjugate conduction and radiation across the helium riser channels in the reactor side reflector. After testing the phenomenological models in isolation, the comprehensive reactor model was tested by simulating the SANA experiment and HTR-10 reactor experiments published by the IAEA. Several sensitivity studies were performed to assess the effect of physical as well as numerical parameters. Two reactor discretisation schemes were also evaluated, namely the control-volume based scheme and the element-based scheme. The control-volume based scheme was found to provide a simpler and more intuitive framework for implementing mathematical models, but not to increase accuracy directly. The most significant finding was that the newly developed second-order accurate convection heat transfer scheme gives the greatest improvement in calculation speed by requiring the least number of pebble bed increments. The other important finding was that the methods currently used in many reactor simulation codes for fuel sphere discretisation and radiation heat transfer approximation are appropriate and give adequate accuracy.
Thesis (Ph.D. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2007

Styles APA, Harvard, Vancouver, ISO, etc.

Keshmiri, Amir. « Thermal-hydraulic analysis of gas-cooled reactor core flows ». Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/thermalhydraulic-analysis-of-gascooled-reactor-core-flows(29335acf-a397-4b8c-8217-fd2ee0d26967).html.

Texte intégral

Résumé :

In this thesis a numerical study has been undertaken to investigate turbulent flow and heat transfer in a number of flow problems, representing the gas-cooled reactor core flows. The first part of the research consisted of a meticulous assessment of various advanced RANS models of fluid turbulence against experimental and numerical data for buoyancy-modified mixed convection flows, such flows being representative of low-flow-rate flows in the cores of nuclear reactors, both presently-operating Advanced Gas-cooled Reactors (AGRs) and proposed ‘Generation IV’ designs. For this part of the project, an in-house code (‘CONVERT’), a commercial CFD package (‘STAR-CD’) and an industrial code (‘Code_Saturne’) were used to generate results. Wide variations in turbulence model performance were identified. Comparison with the DNS data showed that the Launder-Sharma model best captures the phenomenon of heat transfer impairment that occurs in the ascending flow case; v^2-f formulations also performed well. The k-omega-SST model was found to be in the poorest agreement with the data. Cross-code comparison was also carried out and satisfactory agreement was found between the results.The research described above concerned flow in smooth passages; a second distinct contribution made in this thesis concerned the thermal-hydraulic performance of rib-roughened surfaces, these being representative of the fuel elements employed in the UK fleet of AGRs. All computations in this part of the study were undertaken using STAR-CD. This part of the research took four continuous and four discrete design factors into consideration including the effects of rib profile, rib height-to-channel height ratio, rib width-to-height ratio, rib pitch-to-height ratio, and Reynolds number. For each design factor, the optimum configuration was identified using the ‘efficiency index’. Through comparison with experimental data, the performance of different RANS turbulence models was also assessed. Of the four models, the v^2-f was found to be in the best agreement with the experimental data as, to a somewhat lesser degree were the results of the k-omega-SST model. The k-epsilon and Suga models, however, performed poorly. Structured and unstructured meshes were also compared, where some discrepancies were found, especially in the heat transfer results. The final stage of the study involved a simulation of a simplified 3-dimensional representation of an AGR fuel element using a 30 degree sector configuration. The v^2-f model was employed and comparison was made against the results of a 2D rib-roughened channel in order to assess the validity and relevance of the precursor 2D simulations of rib-roughened channels. It was shown that although a 2D approach is extremely useful and economical for ‘parametric studies’, it does not provide an accurate representation of a 3D fuel element configuration, especially for the velocity and pressure coefficient distributions, where large discrepancies were found between the results of the 2D channel and azimuthal planes of the 3D configuration.

Styles APA, Harvard, Vancouver, ISO, etc.

Uyanwaththa, Asela R. « CFD modelling of gas turbine combustion processes ». Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/34686.

Texte intégral

Résumé :

Stationary gas turbines manufacturers and operators are under constant scrutiny to both reduce environmentally harmful emissions and obtain efficient combustion. Numerical simulations have become an integral part of the development and optimisation of gas turbine combustors. In this thesis work, the gas turbine combustion process is analysed in two parts, a study on air-fuel mixing and turbulent combustion. For computational fluid dynamic analysis work the open-source CFD code OpenFOAM and STAR-CCM+ are used. A fuel jet injected to cross-flowing air flow is simplified air-fuel mixing arrangement, and this problem is analysed numerically in the first part of the thesis using both Reynolds Averaged Navier Stokes (RANS) method and Large Eddy Simulation (LES) methods. Several turbulence models are compared against experimental data in this work, and the complex turbulent vortex structures their effect on mixing field prediction is observed. Furthermore, the numerical methods are extended to study twin jets in cross-flow interaction which is relevant in predicting air-fuel mixing with arrays of fuel injection nozzles. LES methods showed good results by resolving the complex turbulent structures, and the interaction of two jets is also visualised. In this work, all three turbulent combustion regimes non-premixed, premixed, partially premixed are modelled using different combustion models. Hydrogen blended fuels have drawn particular interest recently due to enhanced flame stabilisation, reduced CO2 emissions, and is an alternative method to store energy from renewable energy sources. Therefore, the well known Sydney swirl flame which uses CH4: H2 blended fuel mixture is modelled using the steady laminar flamelet model. This flame has been found challenging to model numerically by previous researchers, and in this work, this problem has been addressed with improved combustion modelling approach with tabulated chemistry. Recognizing that the current and future gas turbine combustors operate on a mixed combustion regime during its full operational cycle, combustion simulations of premixed/partially premixed flames are also performed in this thesis work. Dynamical artificially thickened flame model is implemented in OpenFOAM and validated using propagating and stationary premixed flames. Flamelet Generated Manifold (FGM) methods are used in the modelling of turbulent stratified flames which is a relatively new field of under investigation, and both experimental and numerical analysis is required to understand the physics. The recent experiments of the Cambridge stratified burner are studied using the FGM method in this thesis work, and good agreement is obtained for mixing field and temperature field predictions.

Styles APA, Harvard, Vancouver, ISO, etc.

Palipana, Aruna Susantha. « CFD modelling of natural gas combustion in spark ignited engines ». Thesis, Loughborough University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327653.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Walker, David Howey. « CFD Modelling of Sewage Sludge Vitrification Plant ». Thesis, University of Canterbury. Chemical and Process Engineering, 2008. http://hdl.handle.net/10092/1717.

Texte intégral

Résumé :

This Technology in Industry Fellowship (TIF) funded Masters Project was structured around Computational Fluid Dynamics (CFD) modelling for Lemar Environmental Ltd (Lemar). This study is a component of a larger programme that is being undertaken by Lemar concerning the vitrification process. The modelling has built on an initial model developed by CSIRO for Lemar and has been carried out under the direction of Canterbury University. The modelling involved computer simulations and detailed comparisons of the gas flow for both high and low swirl vanes, in both the steady state and transient modes. The output of this activity; velocity profiles (tangential and axial), vorticity, as well as particle tracking (in steady state mode only) were compared to literature and evaluated for both scenarios. As the study was restricted to the gas flow in transient mode, no recommendations and extrapolated modifications to the burner geometry and plant equipment can be made as they have to be verified by the particle motion within the gas flow. The steady state particle simulations obtained through this project, did not provide sufficient evidence to conclude that particles attach to the outer wall and only demonstrated the influences that the high and low swirl had on the particles. Further investigations of transient particle tracking would provide an overall interpretation as to whether or not the dried sludge particles bounced or stuck to the viscous slag layer and a commentary as to their movement in the chamber. Lemar's strategic vitrification programme is still active and the resulting redesign process is nearing completion and modifications to the plant are expected to be finalised by January 2008. Following extensive testing by Lemar it is understood that they would be looking to seek venture capital in order to progress the project to the market. In order for the final stage of the sewage sludge vitrification plant project to commence, Lemar has been in consultation with subject matter experts in the field, as well as undertaking trials on the plant, computer modelling and research into both the technical and international marketing prospects for the combustion technology. The detailed analysis and research undertaken through the CFD modelling conducted for this Project, recommends that Lemar conducts further CFD modelling to investigate transient particle tracking before any plant or geometry modifications are proposed and undertaken in order to optimise the ash capture which is a key output of the vitrification process.

Styles APA, Harvard, Vancouver, ISO, etc.

Johnson, S. Rejish Lal. « Thermal gas radiation modelling for CFD simulation of rocket thrust chamber ». Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264357.

Texte intégral

Résumé :

Methane and oxygen are a promising propellant combination in future rocket propulsion engines mainly due to its advantages like reusability and cost reduction. In order to have a comprehensive understanding of this propellant combination extensive research work is being done. Especially, for reusable rocket engines the thermal calculations become vital as an effective and efficient cooling system is crucial for extending the engine life. The design of cooling channels may significantly be influenced by radiation. Within the framework of this thesis, the gas radiation heat transfer is modelled for CFD simulation of rocket thrust chambers and analysed for the 𝐶𝐻4/𝑂2 fuel combination. The radiation is modelled within ArianeGroup’s in-house spray combustion CFD tool - Rocflam3, which is used to carry out the simulations. Radiation properties can have strong influence for certain chemical compositions, especially 𝐶𝑂2 and 𝐻2𝑂 which are the products of the 𝐶𝐻4 and 𝑂2 combustion. A simplified gas radiation transport equation is implemented along with various spectral models which compute the gas emissivity for higher temperature. Also, Rocflam-II code which has an existing gas radiation model is used to compare and validate the simplified model. Finally the combination of the convective and radiative heat transfer values are compared to the experimental test data. In contrast to the previously existing emissivity models with a certain temperature limit, the model used here enables the inclusion for the total emissivity of 𝐶𝑂2 and 𝐻2𝑂 for temperatures up to 3400 K and hence more appropriate for hydrocarbon combustion in space propulsion systems. It turns out that the gas radiation is responsible for 2-4% of the total heat flux for a 𝐶𝐻4/𝑂2 combustion chamber with maximum integrated temperature of 2700 K. The influence of gas radiation would be greater than 4% respective of the integrated temperature. Gas radiation heat flux effects are higher in stream-tube combustion zone compared to the other sections of the thrust chamber. The individual contribution of radiative heat flux by 𝐶𝑂2 was noted to be 1.5-2 times higher than that to 𝐻2𝑂. It was shown that the analytically derived simplified expression for gas radiation along with the various spectral models had reasonable approximation of the measured radiation. The estimated radiation was correct to the measured radiation from the Rocflam-II model for a temperature range of 400-3400 K.
Metan och syre är en lovande kombination av drivmedel i framtida raketframdrivningsmotorer främst på grund av dess fördelar som återanvändbarhet och kostnadsminskning. För att få en omfattande förståelse av denna drivmedelkombination görs ett omfattande forskningsarbete. Speciellt för återanvändbara raketmotorer blir värmeberäkningarna viktiga eftersom ett effektivt och effektivt kylsystem är avgörande för att förlänga livslängden på motorn. Utformningen av kylkanaler kan betydligt påverkas av strålning. Inom ramen för denna avhandling modelleras gasstrålningsvärmeöverföringen för CFD-simulering av rakettryckkamrar och analyseras för 𝐶𝐻4/𝑂2 -bränslekombinationen. Strålningen är modellerad i ArianeGroup’s egen förbränning CFD-verktyg - Rocflam3, som används för att utföra simuleringarna. Strålningsegenskaper kan ha starkt inflytande för vissa kemiska kompositioner, särskilt 𝐶𝑂2 och 𝐻2𝑂 som är produkterna från förbränningen 𝐶𝐻4 och 𝑂2. En förenklad gasstrålningstransportekvation implementeras tillsammans med olika spektralmodeller som beräknar gasemissiviteten för högre temperatur. Dessutom används Rocflam-II-kod som har en befintlig gasstrålningsmodell för att jämföra och validera den förenklade modellen. Slutligen jämförs kombinationen av konvektiva och strålningsvärmeöverföringsvärden med de experimentella testdata. Till skillnad från de tidigare existerande utsläppsmodellerna med en viss temperaturgräns möjliggör modellen som används här att inkludera den totala emissiviteten för 𝐶𝑂2 och 𝐻2𝑂 för temperaturer upp till 3400 K och därmed mer lämplig för kolväteförbränning i rymdframdrivningssystem. Det visar sig att gasstrålningen svarar för 2-4% av det totala värmeflödet för en 𝐶𝐻4/𝑂2 förbränningskammare med maximal integrerad temperatur på 2700 K. Påverkan av gasstrålning skulle vara större än 4% av den integrerade temperaturen. Effekter på värmeströmning av gasstrålning är högre i strömrörs förbränningszon jämfört med de andra sektionerna av tryckkammaren. Det individuella bidraget från strålningsvärmeflöde med 𝐶𝑂2 noterades vara 1.5-2 gånger högre än det 𝐻2𝑂. Det visades att det analytiskt härledda förenklade uttrycket för gasstrålning tillsammans med de olika spektralmodellerna hade en rimlig tillnärmning av det uppmätta strålning. Den uppskattade strålningen var korrekt den uppmätta strålningen från Rocflam-II-modellen för ett temperaturintervall på 400-3400 K.

Styles APA, Harvard, Vancouver, ISO, etc.

Samee, Lal Rejish Lal Johnson. « Thermal gas radiation modelling for CFD simulation of rocket thrust chamber ». Thesis, KTH, Kraft- och värmeteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-261230.

Texte intégral

Résumé :

Styles APA, Harvard, Vancouver, ISO, etc.

Armstrong, Lindsay-Marie. « CFD modelling of the gas-solid flow dynamics and thermal conversion processes in fluidised beds ». Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/192155/.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Tian, Zhaofeng, et rmit tian@gmail com. « Numerical Modelling of Turbulent Gas-Particle Flow and Its Applications ». RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080528.150211.

Texte intégral

Résumé :

The aim of this thesis is three-fold: i) to investigate the performance of both the Eulerian-Lagrangian model and the Eulerian-Eulerian model to simulate the turbulent gas-particle flow; ii) to investigate the indoor airflows and contaminant particle flows using the Eulerian-Lagrangian model; iii) to develop and validate particle-wall collision models and a wall roughness model for the Eulerian-Lagrangian model and to utilize these models to investigate the effects of wall roughness on the particle flows. Firstly, the Eulerian-Lagrangian model in the software package FLUENT (FLUENT Inc.) and the Eulerian-Eulerian model in an in-house research code were employed to simulate the gas-particle flows. The validation against the measurement for two-phase flow over backward facing step and in a 90-degree bend revealed that both CFD approaches provide reasonably good prediction for both the gas and particle phases. Then, the Eulerian-Lagrangian model was employed to investigate the indoor airflows and contaminant particle concentration in two geometrically different rooms. For the first room configuration, the performances of three turbulence models for simulating indoor airflow were evaluated and validated against the measured air phase velocity data. All the three turbulence models provided good prediction of the air phase velocity, while the Large Eddy Simulation (LES) model base on the Renormalization Group theory (RNG) provided the best agreement with the measurements. As well, the RNG LES model is able to provide the instantaneous air velocity and turbulence that are required for the evaluation and design of the ventilation system. In the other two-zone ventilated room configuration, contaminant particle concentration decay within the room was simulated and validated against the experimental data using the RNG LES model together with the Lagrangian model. The numerical results revealed that the particle-wall coll ision model has a considerable effect on the particle concentration prediction in the room. This research culminates with the development and implementation of particle-wall collision models and a stochastic wall roughness model in the Eulerian-Lagrangian model. This Eulerian-Lagrangian model was therefore used to simulate the gas-particle flow over an in-line tube bank. The numerical predictions showed that the wall roughness has a considerable effect by altering the rebounding behaviours of the large particles and consequently affecting the particles motion downstream along the in-line tube bank and particle impact frequency on the tubes. Also, the results demonstrated that for the large particles the particle phase velocity fluctuations are not influenced by the gas-phase fluctuations, but are predominantly determined by the particle-wall collision. For small particles, the influence of particle-wall collisions on the particle fluctuations can be neglected. Then, the effects of wall roughness on the gas-particle flow in a two-dimensional 90-degree bend were investigated. It was found that the wa ll roughness considerably altered the rebounding behaviours of particles by significantly reducing the 'particle free zone' and smoothing the particle number density profiles. The particle mean velocities were reduced and the particle fluctuating velocities were increased when taking into consideration the wall roughness, since the wall roughness produced greater randomness in the particle rebound velocities and trajectories.

Styles APA, Harvard, Vancouver, ISO, etc.

Plus de sources

Livres sur le sujet "CFD modelling for gas coolers"

Palipana, Aruna Susantha. CFD modelling of natural gas combustion in spark ignited engines. 2000.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Center, Ames Research, dir. CFD modelling of bore erosion in two-stage light gas guns. Moffett Field, Calif : National Aeronautics and Space Administration, Ames Research Center, 1998.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Center, Ames Research, dir. CFD modelling of bore erosion in two-stage light gas guns. Moffett Field, Calif : National Aeronautics and Space Administration, Ames Research Center, 1998.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Chapitres de livres sur le sujet "CFD modelling for gas coolers"

Ma, Guowei, Yimiao Huang et Jingde Li. « VCE Overpressure Prediction by CFD Modelling ». Dans Risk Analysis of Vapour Cloud Explosions for Oil and Gas Facilities, 45–79. Singapore : Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-7948-2_3.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Mullis, Andrew M., Aadhithya Priyadharshini Ashok Kumar et Duncan J. Borman. « CFD Modelling of High Pressure Gas Atomization of Liquid Metals ». Dans CFD Modeling and Simulation in Materials Processing 2018, 77–84. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-72059-3_8.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Al Qubeissi, Mansour, Geng Wang, Nawar Al-Esawi, Oyuna Rybdylova et Sergei S. Sazhin. « CFD Modelling of Gas-Turbine Fuel Droplet Heating, Evaporation and Combustion ». Dans Advances in Heat Transfer and Thermal Engineering, 197–201. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4765-6_36.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Chai, Lei, Konstantinos M. Tsamos et Savvas A. Tassou. « Modelling and Evaluation of the Thermohydraulic Performance of Finned-Tube Supercritical Carbon Dioxide Gas Coolers ». Dans Advances in Heat Transfer and Thermal Engineering, 417–21. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4765-6_71.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Ren, Ting, et Zhongwei Wang. « CFD Modelling of Ventilation, Dust and Gas Flow Dispersion Patterns on a Longwall Face ». Dans Proceedings of the 11th International Mine Ventilation Congress, 198–208. Singapore : Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1420-9_17.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Uggenti, A., A. Carpignano, L. Savoldi, R. Zanino et F. Ganci. « Perspective and criticalities of CFD modelling for the analysis of oil and gas offshore accident scenarios ». Dans Risk, Reliability and Safety : Innovating Theory and Practice, 195–201. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742 : CRC Press, 2016. http://dx.doi.org/10.1201/9781315374987-32.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Zhang, Kaiyu, Jirui Hou et Zhuojing Li. « CFD Modelling and Simulation of Drilled Cuttings Transport Efficiency in Horizontal Annulus During Gas Drilling Process : Effect of Gas Injection Method ». Dans Computational and Experimental Simulations in Engineering, 199–211. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-64690-5_19.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Huser, A., A. Vollestad et N. Rivedal. « Accidental underwater release of CO2—CFD modelling of the underwater plume and the subsequent above water gas dispersion ». Dans Risk, Reliability and Safety : Innovating Theory and Practice, 1526–32. Taylor & Francis Group, 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL 33487-2742 : CRC Press, 2016. http://dx.doi.org/10.1201/9781315374987-229.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Ilbas, M., P. Bowen, T. O'Doherty et N. Syred. « CFD MODELLING OF A LOW NOx COMBUSTOR FIRED BY NATURAL GAS AND GAS-OIL ». Dans The Institute of Energy's Second International Conference on Combustion & ; Emissions Control, 189–98. Elsevier, 1995. http://dx.doi.org/10.1016/b978-0-902597-49-5.50021-4.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Attarakih, Menwer, Abdelmalek Hasseine et Hans-Jörg Bart. « CFD Modelling of Bubbly Gas Flow using Coupled OPOSPM-Two-Fluid Model ». Dans Computer Aided Chemical Engineering, 403–8. Elsevier, 2016. http://dx.doi.org/10.1016/b978-0-444-63428-3.50072-2.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Actes de conférences sur le sujet "CFD modelling for gas coolers"

Monzón, Edgar M. L., Thiago F. de Pádua, Marina G. R. Braga et Gabriela C. Lopes. « CFD Preliminary Study of Gas-Solid Flow in FCC Catalyst Coolers ». Dans Modelling, Simulation and Identification / 841 : Intelligent Systems and Control. Calgary,AB,Canada : ACTAPRESS, 2016. http://dx.doi.org/10.2316/p.2016.840-034.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Andrei, Luca, Luca Innocenti, Antonio Andreini, Bruno Facchini et Lorenzo Winchler. « Film Cooling Modelling for Gas Turbine Nozzles and Blades : Validation and Application ». Dans ASME Turbo Expo 2015 : Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-43345.

Texte intégral

Résumé :

The use of Computational Fluid Dynamics (CFD) for modern turbine blade design requires the accurate representation of the effect of film cooling. However, including complete cooling hole discretization in the computational domain requires a substantial meshing effort and leads to a drastic increase in the computing time. For this reason, many efforts have been made to develop lower order approaches aiming at reducing the number of mesh elements and therefore computational resources. The simplest approach models the set of holes as a uniform coolant injection, but it does not allow an accurate assessment of the interaction between hot gas and coolant. Therefore higher order models have been developed, such as those based on localized mass sources in the region of hole discharge. It is here proposed an innovative injection film cooling model (FCM), embedded in a CFD code, to represent the effect of cooling holes by adding local source terms at the hole exit in a delimited portion of the domain, avoiding the meshing process of perforations. The goal is to provide a reliable and accurate tool to simulate film-cooled turbine blades and nozzles without having to explicitly mesh the holes. The validation campaign of the proposed model is composed of two phases. During the first one, results obtained with the film cooling model are compared to experimental data and to numerical results obtained with the full meshing of the cooling holes on a series of test cases, ranging from single row to multi row flat plate, at varying coolant conditions (in terms of blowing and density ratio). Though details of the flow structure downstream of the holes cannot be perfectly captured, this method allows an accurate prediction of the overall flow and performance modifications induced by the presence of the cooling holes, with a strong agreement to complete hole discretization results. In the second phase, a complete film-cooled vane test case has been studied, in order to consider a real injection system and flow conditions. In this case, film cooling model predictions are compared to an in-house developed correlative approach and full CHT 3D-CFD results. Finally, a comparison between film cooling model predictions and experimental data was performed on an actual nozzle of a GE Oil & Gas heavy-duty gas turbine as well, in order to prove the feasibility of the procedure. The presented film cooling model proved to be a feasible and reliable tool to evaluate adiabatic effectiveness, simplifying the design phase avoiding the meshing process of perforations. Also, refining the mesh near the hole exit, FCM results well approximate the solution coming from a full CHT calculation.

Styles APA, Harvard, Vancouver, ISO, etc.

Montomoli, F., P. Adami, S. Della Gatta et F. Martelli. « Conjugate Heat Transfer Modelling in Film Cooled Blades ». Dans ASME Turbo Expo 2004 : Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-53177.

Texte intégral

Résumé :

A reliable and accurate prediction of temperature field in hot components plays a key role in design process of modern gas turbines. The first stages of turbine and the combustor basket are usually subjected to high heat transfer rates and hot gas temperatures exceed the melting point of the employed alloys. The accurate knowledge of temperature distribution could extend the life of critical components through an accurate design of coolant systems. The present work concerns the upgrade of the finite volume CFD (Computational Fluid Dynamic) solver HybFlow, (see Adami et al.[1]) to simulate heat transfer in gas turbine cooling devices. In particular, the conjugate simulation of flow field heat transfer and metal heat conduction has been considered. To this aim, the original solver has been coupled to a routine solving the Fourier equation in solid domain. This modification allows the “conjugate heat transfer” investigation of heat transfer in fluid flow and solid domain simultaneously. The code has been validated through two different test-case applications. The first is a laminar flow over a flat plate, while the second is a film-cooled plate. Finally, a complete 3D film cooled NGV (Nozzle Guide Vane) has been investigated as an example for a more complex application. The simulation couples the thermal field inside the metal and the flow field in the vane, in the two plenum channels and in the six rows of cooling channels as well.

Styles APA, Harvard, Vancouver, ISO, etc.

Peyton-Bruhl, A., D. Belton, A. D. Walker, G. Snowsill et C. Young. « Development of a CFD Based Methodology for Predicting Oil Auto-Ignition in Gas Turbine Bearing Chambers ». Dans ASME Turbo Expo 2019 : Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-92050.

Texte intégral

Résumé :

Abstract The demand for increased efficiencies in modern aeroengines drives designs to higher pressure ratios, temperatures and shaft speeds. Consequently, higher cycle temperatures and parasitic heat loads are likely to become limiting factors in the design of bearing chambers. These chambers are lubricated and cooled with oil and pressurized using air taken from the main gas path. Historically, the temperature and pressure of the sealing air has been low enough to exclude the risk of bearing chamber oil fires caused by oil auto-ignition. However, temperatures are being driven towards the limits set by current design rules. With respect to oil fire risk assessment, current design rules are very conservative as they pessimistically assume the oil is continuously exposed to the maximum temperature expected in operation when determining the minimum residence time required for oil auto-ignition. Improved bearing chamber designs capable of tolerating higher temperatures could therefore be developed by applying a more rational level of conservatism, based on a more physics-based approach (such as considering the effect of an oil droplet being transported through a varying temperature field). In this paper a numerical methodology is developed to provide a pragmatic approach to addressing conservatism in bearing chamber oil fire risk assessment, with respect to oil auto-ignition. An unsteady Eulerian CFD prediction is used to compute the aerothermal flow field within a stylized bearing chamber. A Lagrangian discrete particle method is then used to track the oil droplet trajectories. The time-dependent droplet temperature histories are then used to compute the fractional accumulation of auto-ignition delay time using an empirically derived relationship. Finally, by defining an ‘auto-ignition (AI) energy’ accumulation factor, the methodology assesses whether an individual oil droplet has satisfied the criteria for auto-ignition. The present contribution examines the effects of various modelling parameters on the ‘AI energy’ accumulation factor. These include one/two-way coupling between the air flow and oil droplets, stochastic turbulence modelling of the droplet behavior, and the effect of droplet size and distribution. The work highlights that two-way coupling is required to ensure the thermal effect of the oil is modelled, despite the increased computational demand. Stochastic modelling of interactions between particles and the flow field is also required to capture the spread of particle trajectories and the resulting distribution of particle temperatures. A representative range of droplet sizes must also be simulated as the propensity for oil AI is a function of droplet diameter; the highest risk occurs for the smallest droplets whilst the largest droplets have greater cooling effect on the air flow. Given the extent of model simplification required to allow the work to be completed with a mid-spec desktop computer and the overall scope of the project, a validation of the findings has not been completed. Instead, an experimental validation is proposed as part of future investigation. The authors imagine that with enough investigation and validation, the understanding developed by the work could be applied as part of a computationally efficient industrial design toolset to inform the early stages of product design.

Styles APA, Harvard, Vancouver, ISO, etc.

Stainsby, Richard, Matthew Worsley, Andrew Grief, Ana Dennier, Frances Dawson, Mike Davies, Paul Coddington et Jo Baker. « Development of Local Heat Transfer Models for Safety Assessment of Pebble Bed High Temperature Gas-Cooled Reactor Cores ». Dans Fourth International Topical Meeting on High Temperature Reactor Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/htr2008-58293.

Texte intégral

Résumé :

This paper presents a model developed for determining fuel particle and fuel pebble temperatures in normal operation and transient conditions based on multi-scale modelling techniques. This model is qualified by comparison with an analytical solution in a one-dimensional linear steady state test problem. Comparison is made with finite element simulations of an idealised “two-dimensional” pebble in transient conditions and with a steady state analytical solution in a spherical pebble geometry. A method is presented for determining the fuel temperatures in the individual batches of a multi-batch recycle refuelling regime. Implementation of the multi-scale and multibatch fuel models in a whole-core CFD model is discussed together with the future intentions of the research programme.

Styles APA, Harvard, Vancouver, ISO, etc.

Pearse, M. « Modelling methodology for thermo-electric coolers in CFD ». Dans 2008 2nd Electronics Systemintegration Technology Conference. IEEE, 2008. http://dx.doi.org/10.1109/estc.2008.4684518.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Martelli, Francesco, Paolo Adami, Simone Salvadori, Kam S. Chana et Lionel Castillon. « Aero-Thermal Study of the Unsteady Flow Field in a Transonic Gas Turbine With Inlet Temperature Distortions ». Dans ASME Turbo Expo 2008 : Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-50628.

Texte intégral

Résumé :

CFD prediction of the unsteady aero-thermal interaction in the HP turbine stage, with inlet temperature non-uniformity, requires appropriate unsteady modelling and a low diffusive numerical scheme coupled with suitable turbulence models. This maybe referred to as high fidelity CFD. A numerical study has been conducted by the University of Florence in collaboration with ONERA to compare capabilities and limitations of their CFD codes for such flows. The test vehicle used for the investigation is a turbine stage of three-dimensional design from the QinetiQ turbine facility known as MT1. This stage is a high pressure (HP) transonic stage that has an un-shrouded rotor, configured un-cooled with 32 stators and 60 rotor blades. Two different CFD solvers are compared that use different unsteady treatment of the interaction. A reduced count ratio technique has been used by the University of Florence with its code HybFlow, while a phase lag model has been used by ONERA in their code, elsA. Four different inlet conditions have been simulated and compared with a focus on the experimental values provided by QinetiQ in the frame of TATEF and TATEF2 EU 6th Framework projects. The differences in terms of performance parameters and hot fluid redistribution, as well as the time- and pitch-averaged radial distributions on a plane downstream of the rotor blade, have been underlined. Special attention was given to the predictions of rotor blade unsteady pressure and heat transfer rates.

Styles APA, Harvard, Vancouver, ISO, etc.

Dixon, Jeffrey A., Antonio Guijarro Valencia, Daniel Coren, Daniel Eastwood et Christopher Long. « Main Annulus Gas Path Interactions : Turbine Stator Well Heat Transfer ». Dans ASME Turbo Expo 2012 : Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-68588.

Texte intégral

Résumé :

This paper summarises the work of a 5-year research programme into the heat transfer within cavities adjacent to the main annulus of a gas turbine. The work has been a collaboration between several gas turbine manufacturers, also involving a number of universities working together. The principal objective of the study has been to develop and validate computer modelling methods of the cooling flow distribution and heat transfer management, in the environs of multi-stage turbine disc rims and blade fixings, with a view to maintaining component and sub-system integrity, whilst achieving optimum engine performance and minimising emissions. A fully coupled analysis capability has been developed using combinations of commercially available and in-house computational fluid dynamics (CFD) and finite element (FE) thermo-mechanical modelling codes. The main objective of the methodology is to help decide on optimum cooling configurations for disc temperature, stress and life considerations. The new capability also gives us an effective means of validating the method by direct use of disc temperature measurements, where otherwise, additional and difficult to obtain parameters, such as reliable heat flux measurements, would be considered necessary for validation of the use of CFD for convective heat transfer. A two-stage turbine test rig has been developed and improved to provide good quality thermal boundary condition data with which to validate the analysis methods. A cooling flow optimisation study has also been performed to support a re-design of the turbine stator well cavity, to maximise the effectiveness of cooling air supplied to the disc rim region. The benefits of this design change have also been demonstrated on the rig. A brief description of the test rig facility will be provided together with some insights into the successful completion of the test programme. Comparisons will be provided of disc rim cooling performance, for a range of cooling flows and geometry configurations. The new elements of this work are the presentation of additional test data and validation of the automatically coupled analysis method applied to a partially cooled stator well cavity, (i.e. including some local gas ingestion); also the extension of the cavity cooling design optimisation study to other new geometries.

Styles APA, Harvard, Vancouver, ISO, etc.

King, Phil T., Gordon E. Andrews, Myeong N. Kim, Mohamed Pourkashanian et Andy C. McIntosh. « CFD Prediction and Design of Low NOx Radial Swirler Systems ». Dans ASME Turbo Expo 2009 : Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-60107.

Texte intégral

Résumé :

A radial swirler with vane passage fuel injection using a radial fuel spoke with one fuel hole per passage was investigated using CFD at 0.5 equivalence ratio and 600K inlet temperature at 1 bar. Experimental measurements of the internal flame composition from water cooled gas sample probes were the experimental results used for comparison. Three combustion models were compared: flamelet with two difference kinetic schemes; PDF transport with two step chemistry and finite rate eddy dissipation model. Both models consistently underpredicted the turbulent flame thickness to 90% heat release by a factor of about 2. The PDF model with postprocessing NOx predictions over estimated the NOx emissions considerably and the best model was the flamelet model with full chemistry. The under prediction of the turbulent reaction zone thickness was concluded to be due to inadequate modelling of strained flame quenching for very lean flames with large laminar flame thickness and very low burning velocities. This flamelet model was applied to predict the influence of the radial swirler outlet geometry on the flame development, fuel and air mixing and NOx emissions. A dump expansion from the radial swirler outlet was compared with the addition of a shroud at the outlet and with the addition of a 60mm long outlet throat. The shroud was shown to increase the peak turbulence and confine it very close to the shroud lip. This improved the fuel and air mixing and lowered the predicted NOx from 2.7ppm to 1.2ppm with the shrouded swirler and 0.3ppm with the 60mm outlet throat and mixing length.

Styles APA, Harvard, Vancouver, ISO, etc.

Wilson, A. J. W., P. T. Ireland, R. Stevenson, S. J. Thorpe et D. Martin. « A Robust Radial Traverse Temperature Probe for Application to a Gas Turbine HP/IP Stage ». Dans ASME Turbo Expo 2012 : Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-68331.

Texte intégral

Résumé :

The requirements to reduce engine fuel burn costs and gaseous emissions combine to ensure that gas turbine engine manufacturers continually seek to increase the peak cycle temperatures of new engine designs. Consequently, high-pressure turbine components must be developed that can withstand increasing gas temperatures, resulting in the continuous introduction of new technologies that allow appropriate service life. Accurate gas path measurements are vital for early understanding of the performance of a new design, although the accurate measurement of fluid temperature in a turbine stage is becoming increasingly difficult. The use of active probe-assembly cooling is important to ensure a sufficiently robust measurement system. Cooling issues may also affect the measurement performance because the component to which the temperature instrumentation is attached is cooled (for example, a guide vane). The use of a radial traverse total temperature device in the turbine section of a large civil aero-engine has previously been reported and the results analysed and compared to expectation. One outcome of ongoing work has been a proposal for a new design of turbine traverse probe with improved total temperature measurement accuracy. The new design directly addresses those uncertainties caused by conduction of heat from the thermocouple junction and into the cooled probe support. Extensive conjugate CFD modelling followed by validation tests in a high temperature free-jet rig confirmed the success of the design in reducing the magnitude of the thermal conduction error. The probe is likely to be used in future tests to improve engine performance validation.

Styles APA, Harvard, Vancouver, ISO, etc.

Nous offrons des réductions sur tous les plans premium pour les auteurs dont les œuvres sont incluses dans des sélections littéraires thématiques. Contactez-nous pour obtenir un code promo unique!