Effects of Hydrogen Addition on the Entropy Generation of Biogas Conventional Combustion

Biogas has a great potential to be applied for heat and power generation throughout the world due to its availability from various resources. However, one of the most important barriers of biogas utilization development is its low calorific value. In order to increase the performance of biogas in industrial application, hydrogen enriched biogas could be substituted. In this paper a set of numerical simulations were conducted to estimate the variation of entropy generation in hydrogen enriched biogas flames due to hydrogen addition to the fuel. Reynolds Averaged Navier Stokes with a second order turbulence closure and laminar flamelet combustion model was applied to compute energy fields and flow in the flame. It was found that hydrogen enrichment resulted in an augmentation in the entropy generation rate of the biogas conventional flame. Such increase could be attributed to the increase in irreversibilities due to biogas flame temperature rise.