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Relevant bibliographies by topics / Preferential diffusion

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Academic literature on the topic 'Preferential diffusion'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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Journal articles on the topic "Preferential diffusion"

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Axelbaum, R. L., C. K. Law, and W. L. Flower. "Preferential diffusion and concentration modification in sooting counterflow diffusion flames." Symposium (International) on Combustion 22, no. 1 (1989): 379–86. http://dx.doi.org/10.1016/s0082-0784(89)80044-x.

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Zeng, An, Alexandre Vidmer, Matúš Medo, and Yi-Cheng Zhang. "Information filtering by similarity-preferential diffusion processes." EPL (Europhysics Letters) 105, no. 5 (2014): 58002. http://dx.doi.org/10.1209/0295-5075/105/58002.

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Takagi, Toshimi, and Xu Zhe. "Numerical Analysis of Hydrogen-Methane Diffusion Flames. Effects of Preferential Diffusion." Transactions of the Japan Society of Mechanical Engineers Series B 59, no. 558 (1993): 607–12. http://dx.doi.org/10.1299/kikaib.59.607.

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Chen, Guilin, Tianrun Gao, Xuzhen Zhu, Hui Tian, and Zhao Yang. "Personalized recommendation based on preferential bidirectional mass diffusion." Physica A: Statistical Mechanics and its Applications 469 (March 2017): 397–404. http://dx.doi.org/10.1016/j.physa.2016.11.091.

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Watson, J., and T. W. Zerda. "Diffusion and Preferential Adsorption of Sol-Gel Glass." Applied Spectroscopy 45, no. 8 (1991): 1360–65. http://dx.doi.org/10.1366/0003702914335689.

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KOMIYAMA, Masaharu, Yasushi DOUURA, Su-Jin CHOI, Akira MIYAFUJI, and Toshimi TAKAGI. "Visualization of Influence of Preferential Diffusion in Jets." Transactions of the Japan Society of Mechanical Engineers Series B 63, no. 607 (1997): 1008–12. http://dx.doi.org/10.1299/kikaib.63.1008.

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TAKAGI, Toshimi, Zhe XU, and Masaharu KOMIYAMA. "Effects and Evaluation of Preferential Diffusion in Flames." Transactions of the Japan Society of Mechanical Engineers Series B 62, no. 595 (1996): 1218–25. http://dx.doi.org/10.1299/kikaib.62.1218.

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Kim, Jeong Soo, Jeong Park, Oh Boong Kwon, Jin Han Yun, Sang In Keel, and Tae Kwon Kim. "Preferential Diffusion Effects on NO Formation in Methane/Hydrogen-Air Diffusion Flames." Energy & Fuels 22, no. 1 (2008): 278–83. http://dx.doi.org/10.1021/ef700505a.

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Takagi, Toshimi, Zhe Xu, and Masaharu Komiyama. "Preferential diffusion effects on the temperature in usual and inverse diffusion flames." Combustion and Flame 106, no. 3 (1996): 252–60. http://dx.doi.org/10.1016/0010-2180(95)00255-3.

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Ma, Y., and L. D. Marks. "Knockcn surface diffusion." Proceedings, annual meeting, Electron Microscopy Society of America 44 (August 1986): 394–95. http://dx.doi.org/10.1017/s0424820100143572.

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There is growing interest in the use of electron microscopy to study surfaces. Unfortunately, the electron beam used to obtain images can also lead to surface modifications. Two processes can occur: electronic transitions which become converted into atomic motion leading either to preferential desorption of one species or athermal surface diffusion, and ballistic surface sputtering or diffusion. We report here preliminary theoretical results for this latter process, athermal surface diffusion due to ballistic Rutherford scattering.

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Dissertations / Theses on the topic "Preferential diffusion"

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Boyer, Denis, and Inti Pineda. "Ultra-slow diffusion in processes with preferential relocations to places visited in the past." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-198045.

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Boyer, Denis, and Inti Pineda. "Ultra-slow diffusion in processes with preferential relocations to places visited in the past." Diffusion fundamentals 24 (2015) 7, S. 1, 2015. https://ul.qucosa.de/id/qucosa%3A14521.

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Bertali, Giacomo. "Mechanistic understanding of Alloy 600 preferential intergranular oxidation : 'precursor events of stress corrosion cracking'." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/mechanistic-understanding-of-alloy-600-preferential-intergranular-oxidation-precursor-events-of-stress-corrosion-cracking(db6c7668-7cf5-4d50-a6bf-34eacf5b1216).html.

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Primary Water Stress Corrosion Cracking (PWSCC) of Alloy 600 and similar Ni-Cr-Fe alloys is regarded as one of the most important challenges to nuclear power plant operation. During the past decades the majority of research has focused on PWSCC crack growth rate measurements in order to assess the lifetime of real components and to develop empirical models for crack propagation. However, the incubation and initiation stages of PWSCC have the same or even greater importance than the propagation stage, particularly because SCC can be undetected for more than 20 years before the occurrence of a rapid and catastrophic failure. There is, therefore, the scientific need to understand the mechanisms playing a fundamental role in the formation and development of intergranular cracks embryo, the so-called SCC initiation "precursor events", in order to be able to predict and mitigate the occurrence of PWSCC. Amongst all the models proposed for SCC initiation, the internal oxidation mechanism proposed by Scott and Le Calvar in 1992 appears to be the most comprehensive. Although the internal oxidation mechanism is widely accepted, it still requires further elucidation, especially in terms of enhanced grain boundary diffusivity and the role of intergranular carbides on the oxidation mechanism. The present work has focused on the initial stages of intergranular oxidation of solution-annealed (SA) and thermally-treated (TT) Alloy 600 with the aim of understanding the active mechanism responsible for the enhanced intergranular oxide penetration kinetics. The material was tested in simulated PWR primary water at 320°C, high-pressure hydrogenated-steam at 400°C and low-pressure H2-steam environment at 480°C at potential more reducing than the Ni/NiO equilibrium. The detailed microstructural characterization was conducted using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and analytical transmission electron microscopy (ATEM) and demonstrated that Alloy 600SA is susceptible to diffusion-induced grain boundary migration (DIGM), preferential intergranular oxidation (PIO) and localised Cr and Fe depletions at the grain boundaries. The similar analyses performed on Alloy 600TT demonstrated reduced susceptibility to PIO and grain boundary migration. Further, detailed analyses confirmed that intergranular carbides were readily oxidized/consumed in all 3 environments and acted as Cr reservoir/O trap. These results shed additional light on the "precursor events" for PWSCC of Alloy 600, especially on the mechanism responsible for the enhanced Cr and O diffusivity and on the mechanism responsible for the enhanced Alloy 600TT SCC initiation resistance. Moreover, the strong similarities in the Alloy 600 oxidation behaviour observed for the 3 different environments and at the 3 different temperatures suggested that the same PIO mechanism is active in both steam and water and at temperatures between 320°C and 480°C. These results strongly support the possibility of using the low-pressure H2-steam environment as a substitute environment to accelerate PWSCC initiation without changing the mechanism.

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Lindsay, John Christopher. "Stress corrosion cracking and internal oxidation of alloy 600 in high temperature hydrogenated steam and water." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/stress-corrosion-cracking-and-internal-oxidation-of-alloy-600-in-high-temperature-hydrogenated-steam-and-water(1d6b037c-baf1-4397-a6c9-43835e7bb39a).html.

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In this study, the possibility of using low pressure hydrogenated steam to simulate primary water reactor conditions is examined. The oxides formed on Alloy 600 (WF675) between 350 Celsius and 500 Celsius in low pressure hydrogenated steam (with a ratio of oxygen at the Ni/NiO to oxygen in the system of 20) have been characterised using analytical electron microscopy (AEM) and compared to oxide that formed in a high pressure water in a autoclave at 350 Celsius with 30 cc/kg of hydrogen. Preferential oxidation of grain boundaries and bulk internal oxidation were observed on samples prepared by oxide polishing suspension (OPS). Conversely, samples mechanically ground to 600 grit produced a continuous, protective oxide film which suppressed the preferential and internal oxidation. The surface preparation changed the form of the oxides in both steam and autoclave tests. The preferential oxidation rate has been determined to be K_{oxide} = Aexp{-Q/RT}with A = 2.27×10^(−3) m^(2)s^(−1) and Q = 221 kJ.mol^(−1) (activation energy) for WF675 and A = 5.04 × 10^(−7) m^(2)s^(−1) and Q = 171 kJ.mol^(−1) for 15% cold worked WF675. These values are consistent with the activation energy of primary water stress corrosion cracking (PWSCC) initiation. Bulk oxygen diffusivities were calculated from the internal oxidation after 500 h exposures. At 500 Celsius the oxygen diffusivity was determined to be 1.79×10^(−20) m^(2)s^(−1) for WF675 and 1.21×10^(−20) m^(2)s^(−1) for 15% cold worked WF675, the oxygen diffusivity at 400 Celsius in 15% cold worked WF675 was calculated to be 1.49×10^(−22) m^(2)s^(−1).The Cr-depletion associated with preferential oxidation has been assessed by AEM. The Cr-depletion was asymmetric and it could not be accounted for by local variations in the diffusion rate. Chemically induced grain boundary migration is suggested as a possible explanation. Constant load SCC tests conducted in hydrogenated steam at 400 Celsius have shown a similar trend to the classical dependency of PWSCC as a function of potential. The SCC samples were also prepared with two surface finishes, OPS and 600 grit. In all SCC tests, significantly more cracking was observed on the OPS surface and all failures initiated from this surface.

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Books on the topic "Preferential diffusion"

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Börzel, Tanja A., and Soo Yeon Kim. The International Political Economy of Regionalism. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190228637.013.173.

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Economic regionalism has been dominated by preferential trade agreements (PTAs). Not only have their numbers surged since the end of the Cold War, we also see different varieties of PTAs emerging. First, long-standing PTAs have evolved into deeper forms of economic regionalism, such as custom unions, common markets, or currency unions. Second, PTAs increasingly involve “behind-the-border” trade liberalization, such as the coordination of domestic trade–related regulatory standards. Third, many of the PTAs that were established over the past 25 years no longer only involve countries of the “Global North” but are formed by developing and developed countries (“North-South” PTAs) and between developing countries (“South-South” PTAs). Finally, a most recent development in economic regionalism concerns the building of so called “mega-PTAs,” such as the Trans-Pacific Partnership (TTP) and the Transatlantic Trade and Investment Partnership (TTIP), combining several PTAs.In order to explain the formation, proliferation, and evolution of these varieties of PTA, existing international political economy (IPE) approaches have to give more credit to political factors, such as the locking-in of domestic reforms or the preservation of regional stability. Moreover, IPE scholarship should engage more systematically with diffusion research, particularly to account for the spate of deeper regionalism. Finally, “rising powers” and “emerging markets” constitute an exciting new research area for IPE. These new players differ with regard to the importance they attribute to regionalism and the ways in which they have sought to use and shape it. Identifying and explaining variations in the link between rising powers and regionalism is a key challenge for future research

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Book chapters on the topic "Preferential diffusion"

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Heron, Tony. "European Policy Diffusion and the Politics of Regional Integration in the Pacific." In Pathways from Preferential Trade. Palgrave Macmillan UK, 2013. http://dx.doi.org/10.1057/9781137307927_4.

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He, Chaocheng, Guiyan Ou, and Jiang Wu. "Characterizing Research Leadership Flow Diffusion: Assortative Mixing, Preferential Attachment, Triadic Closure and Reciprocity." In Diversity, Divergence, Dialogue. Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-71292-1_17.

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Giona, Massimiliano, Manuela Giustiniani, and Antonio Viola. "Monte Carlo Simulations of Preferential Adsorption: the Effects of Energetic Heterogeneity and of Surface Diffusion." In The Kluwer International Series in Engineering and Computer Science. Springer US, 1996. http://dx.doi.org/10.1007/978-1-4613-1375-5_38.

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Niwa, Miki, Takehisa Kunieda, and Jong-Ho Kim. "What Preferentially Determines theparaShape Selectivity: Diffusion of Molecules or External Surface Acidity." In ACS Symposium Series. American Chemical Society, 1999. http://dx.doi.org/10.1021/bk-2000-0738.ch012.

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Takagi, Toshimi, and Zhe Xu. "Effects of Preferential Diffusion of Heat and Species in Diffusion Flames." In Turbulence and Molecular Processes in Combustion. Elsevier, 1993. http://dx.doi.org/10.1016/b978-0-444-89757-2.50032-7.

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Buchmayr, B., and J. S. Kirkaldy. "Preferential concentration and depletion of carbides after annealing of mismatched chromium alloy weldments." In Fundamentals and Applications of Ternary Diffusion. Elsevier, 1990. http://dx.doi.org/10.1016/b978-0-08-040412-7.50024-4.

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"Flame Curvature as a Determinant of Preferential Diffusion Effects in Premixed Turbulent Combustion." In Advances in Combustion Science: In Honor of Ya. B. Zel'dovich. American Institute of Aeronautics and Astronautics, 1997. http://dx.doi.org/10.2514/5.9781600866456.0235.0250.

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Wunderlich, Wilfried, Janos Lendvai, and Hans-Joachim Gudladt. "Microstructure Imaging, Precipitation Formation and Mechanical Properties: Al–Li and Al–Mg–Zn Alloys." In Encyclopedia of Aluminum and Its Alloys. CRC Press, 2019. http://dx.doi.org/10.1201/9781351045636-140000219.

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This article describes concepts of three features of microstructure–properties relationship, first the imaging and formation of nano-particles, then their contribution to hardness, and finally hydrogen embrittlement during fatigue. First, we briefly review the imaging modes in transmission electron microscopy (TEM) for nano-sized precipitates. The next issue is the hardening in Aluminum alloys, which is caused by GP-zones or precipitates, formed at the second step of the annealing process. After homogenization, the peak-hardness can be generally achieved by a few hours of annealing between 120°C and 200°C. Hardness measurements and equal-channel axial pressing (ECAP) showed that even at room temperature the driving force for formation of the particles is so strong that already within one hour of annealing after homogenization a remarkable hardening occurs. The third issue, hydrogen embrittlement, is caused by oxidation of pure Al surfaces produced at the crack tip during fatigue under ambient or wet moisture conditions. The cracks propagate preferentially along the precipitation free zone adjacent to grain boundaries, where hydrogen diffusion is fastest.

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Conference papers on the topic "Preferential diffusion"

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Xu, Zhe, and Toshimi Takagi. "EFFECTS OF PREFERENTIAL DIFFUSION OF HEAT AND SPECIES IN REACTING FLOWS." In International Heat Transfer Conference 10. Begellhouse, 1994. http://dx.doi.org/10.1615/ihtc10.4110.

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Lee, S. D., and Suk Ho Chung. "EFFECT OF STRETCH AND PREFERENTIAL DIFFUSION IN SPHERICALLY PROPAGATING H2/AIR PREMIXED FLAMES." In International Heat Transfer Conference 11. Begellhouse, 1998. http://dx.doi.org/10.1615/ihtc11.4350.

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Leiroz, Albino, Rafael Leitão, Ricardo Soares, and Marcelo Colaco. "A Numerical Study on the Effects of Preferential Diffusion in Ethanol Laminar Reactive Flows." In 16th Brazilian Congress of Thermal Sciences and Engineering. ABCM, 2016. http://dx.doi.org/10.26678/abcm.encit2016.cit2016-0498.

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Li, Shaoshuai, Yunzhe Zheng, Daniel Mira Martinez, Suhui Li, Min Zhu, and Xi Jiang. "A LES-LEM Study of Preferential Diffusion Processes in a Partially Premixed Swirling Combustor With Synthesis Gases." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-57146.

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A lean partially premixed swirling combustor with synthesis gases is studied using large-eddy simulation (LES). The simulation used the linear-eddy mixing (LEM) model to close the unclosed subgrid scalar flux. Several terms resulting from the LES filter are not modelled but directly resolved considering their unique length and time scales, such as the molecular diffusion, scalar mixing and chemical reaction processes. The validation results show that the code and the chemical mechanism used in the present work do have reliable accuracy. With this model, the effects of preferential diffusion process on lean partially premixed swirling combustion are investigated and the results show that the characteristics of flow and combustion dynamics can be profoundly affected. The obtained results are expected to provide helpful information for the design and operation of syngas gas turbine combustor systems.

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Cheng, Way Lee, Cai Shen, and Chia-fon F. Lee. "Application of Continuous Thermodynamics Method to Fuel Droplet Evaporation." In ASME 2012 Internal Combustion Engine Division Fall Technical Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/icef2012-92177.

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A finite diffusion droplet evaporation model for complex liquid mixture composed of different homogeneous groups is presented in this paper. Separate distribution functions are used to describe the composition of each homogeneous group in the mixture. Only a few parameters are required to describe the mixture. Quasi-steady assumption is applied in the determination of evaporation rates and heat flux to the droplet, and the effects of surface regression, finite diffusion and preferential vaporization of the mixture are included in the liquid phase equations using an effective properties approach. A novel approach was used to reduce the transport equations for the liquid phase to a set of ordinary differential equations. The proposed model is capable in capturing the vaporization characteristics of complex liquid mixtures.

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Muppala, Siva P. R., and Miltiadis V. Papalexandris. "A Modeling Approach for Hydrogen-Doped Lean Premixed Turbulent Combustion." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-13861.

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In this study, we investigate some preliminary reaction model predictions analytically in comparison with experimental premixed turbulent combustion data from four different flame configurations, which include i) high-jet enveloped, ii) expanding spherical, iii) Bunsen-like, and iv) wide-angled diffuser flames. The special intent of the present work is to evaluate the workability range of the model to hydrogen and hydrogen-doped hydrocarbon mixtures, emphasizing on the significance of preferential diffusion, PD, and Le effects in premixed turbulent flames. This is carried out in two phases: first, involving pure hydrocarbon and pure hydrogen mixtures from two independent measured data, and second, with the blended mixtures from two other data sets. For this purpose, a novel reaction closure embedded with explicit high-pressure and exponential Lewis number terms developed in the context of hydrocarbon mixtures is used. These comparative studies based on the global quantity, turbulent flame speed, indicate that the model predictions are encouraging yielding proper quantification along with reasonable characterization of all the four different flames, over a broad range of turbulence, fuel-types and for varied equivalence ratios. However, with each flame involved the model demands tuning of the (empirical) constant to allow for either or both of these effects, or for the influence of the burner geometry. This provisional stand remains largely insufficient. Therefore, a submodel for chemical time scale from the leading point analysis based on the critically curved laminar flames employed in earlier studies for expanding spherical flames is introduced here. By combining the submodel and the reaction closure, the dependence of turbulent flame speed on physicochemical properties of the burning mixtures including the strong dependence of preferential diffusion and/or Le effects can be determined.

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Gao, Z., R. V. R. Pandya, B. Shotorban, and F. Mashayek. "Current Issues in Analytical Description of Particle/Droplet-Laden Turbulent Flows." In ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45668.

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The particle/droplet-laden turbulent flows occur in many important natural and technological situations, e.g., cloud [1], aerosol transport and deposition [2], spray combustion [3, 4], fluidized bed combustion [5], plasma spray coating and synthesis of nanoparticles [6]. Undoubtedly, turbulence itself remains as a difficult and unsolved problem of classical mechanics despite many persistent efforts by physicists and engineers. The presence of particles/droplets (hereafter simply referred to as particles) further adds to the complexity of the turbulence. The particle behavior in turbulent flows gives rise to many interesting phenomena, such as, turbophoresis [7], turbulent thermal diffusion and barodiffusion [8, 9], preferential distribution, and anomaly and intermittency [9, 10]. It is challenging to come up with a unique predictive theory for the particle phase which is useful for engineering purposes and also capable in quantifying various related phenomena.

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Menon, Sachin, Thijs Bouten, Jan Withag, Sikke Klein, and Arvind Gangoli Rao. "Numerical Investigation of 100% Premixed Hydrogen Combustor at Gas Turbines Conditions Using Detailed Chemistry." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-16134.

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Abstract The combustion properties of hydrogen make premixed hydrogen-air flames prone to flashback. Several combustor concepts have been proposed and studied in the past few years to tackle the problem of flame flashback in premixed high hydrogen fuel combustors. This study looks at one of the concepts which uses the Aerodynamically Trapped Vortex to stabilize the flame. Burner concepts based on trapped vortex flame stabilization have a higher resistance towards flame blowout than conventional swirl stabilized burners. This work looks at the flow and flame behavior in the proposed Aerodynamically Trapped Vortex Combustor for 100% premixed hydrogen operation. Numerical simulations for the analysis were performed with the commercial CFD simulation package AVL FIRE™. The flow field characterization was focused on the investigation of the influence of both the inlet velocity and inlet turbulence intensity on the mean velocity, wall velocity gradient and turbulence intensity in the combustor. To study the flame stabilization mechanism, reactive simulations were performed at two fuel equivalence ratios. The combustion regime of the flame, turbulent flame speed and temperature distribution in the combustor were quantified from the simulation results. Combustion is modelled using a detailed chemistry solver with the k–ε turbulence model to resolve turbulence. No additional turbulence-chemistry interaction model is used in the current research. To reduce chemistry computational time, the multi-zone method is employed. To capture the effect of preferential diffusion, two approaches were used to quantify the diffusion coefficient of each species. The diffusion coefficients were calculated using both mixture averaged approach and the multi component diffusion approach. The proposed design for the Aero-dynamically Trapped Vortex combustor was able to stabilize a 100% premixed hydrogen flame without flashback for the simulated conditions.

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Sohrabi, Salman, Seyyed Mahdi Nemati Mehr, and Pedram Falsafi. "A Novel Approach for Compensating the Significance of Tubule’s Architecture in Urine Concentrating Mechanism of Renal Medulla." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63747.

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Many theories and mathematical simulations have been proposed concerning urine concentrating mechanism (UCM). The WKM and region approach are the two most valuable methods for compensating the effect of tubule’s architecture in renal medulla. They both have tried to simulate tubule’s confinement within a particular region mathematically in one spatial dimension. In this study, continuity, momentum and species transport equations along with standard expressions for transtubular solutes and water transports on tubule’s membrane were solved numerically in three spatial dimensions which practically is the main significance of our novel approach. Model structure has been chosen as simple as possible to minimize the effect of other factors in tubule’s solute and water exchange. It has been tried to simulate the preferential interaction between tubules by introducing different diffusion coefficients for solutes in the intermediate media in order that changing this physical parameter directly could influence tubule’s confinement with respect to each other. The results have been discussed in detail and then the effect of solute’s diffusivity on UCM has been investigated subsequently. In overall, it has been found out that this simulation can validate the integrity of our proposed approach for further investigation in this field.

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Duan, Zhixuan, Alireza Kalantari, and Vincent McDonell. "Parametric Analysis of Flashback Propensity With Various Fuel Compositions and Burner Materials." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-43629.

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Flashback is a key operability issue for low NOx premixed combustion of hydrogen enriched fuels. Previous work has systematically investigated the impact of fuel composition on flashback propensity and noted the coupling of flashback with burner tip temperature. It led to models for critical velocity gradient as an indicator of flashback propensity as a function of parameters studied, such as fuel composition, burner tip temperature and laminar flame speed, etc. The present work further analyzes existing data and develops an empirical physical model for flashback propensity as a function of dimensionless groups. A comprehensive parameter screening is conducted and the potential variables determining flashback behavior are catalogued into five types: operational parameters, unburnt conditions, ambient conditions, rig properties and others. The objective of the analysis is to predict the critical operational parameters with given unburnt conditions which are generally known to the hardware designer. Other factors, such as ambient conditions and rig properties might also affect the prediction performance. To account for such factors, a dimensional analysis is conducted based on Buckingham Pi theorem. The critical Damköhler number is selected as the indicator of flashback propensity and a model is developed suggesting the significance of preferential diffusion (Le), heat loss (TuT0), thermal coupling effect (TtipTu) and flame Péclet number (Pef) as follows: Da = Const. · Le -6.12 · T u T 0 -1.71 · T tip T u -3.69 Pe f 1.89 · f 1 θ ′ d · f 2 P u P 0 Finally, preliminary results for pressure effects are presented.

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