کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1272694 | 1497495 | 2014 | 17 صفحه PDF | دانلود رایگان |
• Large-eddy simulations of non-reactive and reactive hydrogen jets are presented.
• Two closure models for the subgrid scalar transport of hydrogen-enriched fuels are examined.
• The linear-eddy model produces accurate results when modelling hydrogen mixtures.
• The eddy diffusivity model may lead to unphysical representation of the scalar fields.
• Appropriate modelling of hydrogen mixtures requires accounting for countergradient diffusion.
A comparison of two different models addressing the scalar transport in large-eddy simulations is conducted for a non-reacting jet and an experimental flame. A simple approach based on a gradient diffusion closure is compared against the linear-eddy model in the context of hydrogen-enriched non-reacting fuel jets and flames burning hydrogen-enriched mixtures. The results show that the gradient diffusion model is not valid as a subgrid scale model for large-eddy simulations of mixtures containing hydrogen. It produces unphysical scalar fields with unrealistic temperature distributions. Approaches based on the linear-eddy model can be used instead to obtain appropriate representation of the scalar field and more accurate predictions of the scalar transport and the temperature field.
Journal: International Journal of Hydrogen Energy - Volume 39, Issue 14, 5 May 2014, Pages 7173–7189