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September 28, 2016, 13:41 
Gulder coefficients for Hydrogen gas

#1 
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Shashi
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Hi...
First of all thanks for the forum. I'm simulating Hydrogen fueled engine using Geqn model. To calculate laminar flame speed I'm using Gulder equation but I don't know the gulder coefficients 'omega', 'eta' and 'zeta' for Hydrogen. Can anyone provide the same or any alternate method to get the laminar flame speeds ? Thanks in advance! 

September 29, 2016, 13:50 

#2 
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Shengbai Xie
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Hi,
Currently we don't have those parameters as default for Hydrogen. You may find relevant researches else where. For example, this one: Milton, B.E., Keck, J.C. (1984) Laminar burning velocities in stoichiometric hydrogen and hydrogenhydrocarbon gas mixtures, Combustion and Flame, Volume 58, Issue 1, 1322 You would have to make a custom UDF for the hydrogen parameters as the paper's equations are different from Metghalchi & Keck and Gulder. Hope it helps. 

November 14, 2017, 08:49 
Numerical method to approximate the Gulder coefficient

#3 
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Jonathan Johnsplass
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Hi. I computed the Gulder coefficients for hydrogen and other gas compounds and multicompositions in my master thesis. I developed a python script where i scripted an optimization routine based on the opensource chemical kinetics software Cantera.
I computed the Gulder coefficients for hydrogen with the GRIMech 3.0. Here follows the coefficients for hydrogen: W [m/s] = 2.094 η [] = 1.068 ξ [] = 0.424 R**2 (W,ηξ) [] = 0.97 Φ [] = [0.32.5] α [] = 2.9 R**2 (α) [] =0.99 T [] = [250 K 961 K] β [] = 0.04 R**2 (β) [] =0.78 P [] = [0.5 atm  10 atm] *R**2 = Coefficient of determination *I attached the python files inside a zipfile. 

December 27, 2019, 07:51 

#4 
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Tobias Holzmann
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Hi Jonathan,
is there more information about your scripts available? I opened it but as there is no documentation it is a bit tricky to understand for someone who is not as familiar as you with the stuff. Tobi
__________________
Keep foaming, Tobias Holzmann 

December 29, 2019, 14:33 

#5 
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Jonathan Johnsplass
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Dear Tobias
The aim of the scripts is to estimate the Gulder coefficients by approximating the laminar burning velocity as a function of pressure, temperature and fuelair ratio, and then fitting the Gulder coefficients to the approximated data points. The laminar burning velocity estimate in the provided scripts is based on the class FREEFLAME [1] in Cantera. “Cantera is an opensource suite of objectoriented software tools for problems involving chemical kinetics, thermodynamics, and/or transport processes. The software automates the chemical kinetic, thermodynamic, and transport calculations so that the users can efficiently incorporate detailed chemical thermokinetics and transport models into their calculations.” [2] The alpha parameter is fitted to the data series where the laminar burning velocity is a function of temperature, the beta coefficient is fitted to pressure, and Omega, Eta and Xi is fitted when the laminar burning velocity is a function of equivalence ratio (normalized fuelair ratio). It is necessary to find a chemical kinetic mechanism which contains the combustion species you want to simulate. Most of these mechanisms is in Chemkinformat [3]. It is necessary to convert the files in Chemkin format into the Cantera format CTI. Use the method describe in [4]. The CRECK Modeling Group have several detailed kinetic mechanisms which is Opensource [5], Cerfacs – the Centre of basic and applied research specialized in modelling and numerical simulation also provides kinetic mechanisms [6]. I suggest that you should check out the examples provided in Cantera [7]. You can pm me if you have a certain case you want to simulate. I used this method to generate the results in the paper [8], and the necessary parameters to simulate dimethyl carbonate with XiFOAM in [9]. Reference: [1] https://cantera.org/documentation/do...html#freeflame [2] Goodwin, D. G., Moffat, H. K., & Speth, R. L. (2009). Cantera: An objectoriented software toolkit for chemical kinetics, thermodynamics, and transport processes. Caltech, Pasadena, CA. [3] Kee, R. J., Rupley, F. M., & Miller, J. A. (1989). ChemkinII: A Fortran chemical kinetics package for the analysis of gasphase chemical kinetics (No. SAND898009). Sandia National Labs., Livermore, CA (USA). [4] https://cantera.org/tutorials/ck2ctitutorial.html [5] http://creckmodeling.chem.polimi.it/...ledmechanisms [6] http://www.cerfacs.fr/cantera/ [7] https://cantera.org/examples/python/...exampleonedim [8] Johnsplass, J., Henriksen, M., Vågsæther, K., Lundberg, J., & Bjerketvedt, D. (2017, September). Simulation of burning velocities in gases vented from thermal runaway lithium ion batteries. In Proceedings of the 58th Conference on Simulation and Modelling (SIMS 58) Reykjavik, Iceland, September 25th–27th, 2017 (No. 138, pp. 157161). Linköping University Electronic Press. [9] Johnsplass, J. (2017). Liion battery safety (Master's thesis, Høgskolen i SørøstNorge). 

September 7, 2020, 07:44 
Could you attach your document of how these properties were calculated?

#6  
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Manideep
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June 21, 2022, 05:26 

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Mat
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October 20, 2022, 15:56 

#8 
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Sameera Wijeyakulasuriya
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CONVERGE allows you to read laminar flame speeds from a tabulated table. This will eliminate the need for any correlations. As long as you have a chemical mechanism for the fuel of interest, then we can use CONVERGE 1D solver to generate this table and use in your 3D simulation.


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