| Non-catalytic partial oxidation (NPOX) of natural gas is one of important industrial technology in the production of syngas. Partial oxidation and reforming are crtiacal reactions included in the NPOX process. The methane combustion and reforming occured in the high pressure-temperature reformer is a typical confined diffusion flame. The chemical and physical process in an industrial reformer is intractable by experiment technique. Hence, numerical simulation is a useful tool for investigating the folw, heat transport and reaction in order to develop and design industrial reformer.In this study, the standard Sandia Flame D is simulated by using realizable k-εmodel incorporating with the probability density function (PDF) and the eddy dissipation concept (EDC) approachs, respectively. The results show that both methods provide comparable temperature and concentration fields with the experimental measurements. However, the accuracy of predicted temperature by PDF is very sensitve to the calculation of mixture fraction in the fuel-lean region.A larege eddy simulation (LES) is also performed for the Flame D using the PDF model describing the interactions between turbulence and reactions. Statistical average is conducted over the three dimensional transient field, and the results are compared with the measurements. The results indicate that LES does not improve the accuracy of prediction in view of the temperature and concentration distributions. Farthermore, the tremendous computational load makes the LES an impractical mean in simulating an industrial process.Based on the above validatin results, the realizabale k-εand EDC approach is adapted in the simulation of an industrial scale natural gas reformer operated in Lanzhou Petrochemical fertilizer plant. The results show that EDC provides reansonable flame length and concentration distribution comparing with PDF. This combination is recommended for further study for the design and optimization of the industrial scale reformers.
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