HAL Id: hal-01253371
https://hal.archives-ouvertes.fr/hal-01253371
Submitted on 10 Jan 2016
HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Numerical Investigations of Chemical Kinetics for Methane Catalysis and Pyrolysis
G Fau, Nicolas Gascoin
To cite this version:
G Fau, Nicolas Gascoin. Numerical Investigations of Chemical Kinetics for Methane Catalysis and Pyrolysis. 10th International Symposium on Special Topics in Chemical Propulsion & Energetic Ma- terials (10-ISICP), 2-6 June 2014, Poitiers, France, Paper#117, 2014, Poitiers, France. �hal-01253371�
Numerical Investigations of Chemical Kinetics for Methane Catalysis and Pyrolysis
G. Fau1, N. Gascoin2
1Université d’Orléans, Bourges, France; 2INSA Centre Val de Loire, Bourges, France
Primary Technical Area: Theoretical Modeling and Numerical Simulation Techniques for Chemical Propulsion Topics
Secondary Technical Area: Environmentally-Friendly "Green" Propellants
Extended Abstracts
In the framework of the active and regenerative cooling of hypersonic and space structures, a kinetic mechanism should be proposed to investigate numerically the fuel pyrolysis and the coke formation with a possible surface effect (catalytic reactions). This chemical mechanism should be suitable for Computational Fluid Dynamics approach (limited number of species and reaction). The objective of this study is to obtain a mechanism which permits to compute methane pyrolysis considering both heterogeneous reactions and the coke production.
A
For this purpose, this work presents some homogeneous and heterogeneous calculations of methane chemistry with metallic catalysts in order to test a kinetic mechanism with the integration of surface reactions. Three catalysts are considered: platinum, nickel and rhodium. A mechanism has been selected. Then, its size (i.e. number of reactions and of species) has been reduced. A parametric study is achieved and several reactors natures are tested.
Small differences are noted between the three catalysts for a low value of site density while a strong one appears for a higher one.
0,00%
10,00%
20,00%
30,00%
40,00%
50,00%
60,00%
70,00%
80,00%
90,00%
100,00%
1,E-06 1,E-05 1,E-04 1,E-03 1,E-02 1,E-01 1,E+00 1,E+01 1,E+02 Time (s)
H2 / CH4
0,00%
1,00%
2,00%
3,00%
4,00%
5,00%
6,00%
7,00%
8,00%
C2H2 / C2H4
H2 (Ni) H2 (Rh) CH4 (Ni) CH4 (Rh) C2H2 (Ni) C2H2 (Rh) C2H4 (Ni) C2H4 (Rh)
Figure 1. Effect of catalyst nature on light specie production (mol.%).
Both the product distribution and the dynamic are affected. The reactor type used for the computations has been also tested. The differences are limited considering nickel or platinum catalyst while some important discrepancies are observed for the rhodium.
These simulations have highlighted some differences and demonstrated the importance of the site density value on the results.
