Design and Development of MILD Combustion Burner

This paper discusses the design and development of the Moderate and Intense Low oxygen Dilution (MILD) combustion burner using Computational Fluid Dynamics (CFD) simulations. The CFD commercial package was used to simulate preliminary designs for the burner before the final design was sent to the workshop for fabrication. The burner is required to be a non-premixed and open burner. To capture and use the exhaust gas, the burner was enclosed within a large circular shaped wall with an opening at the top. An external EGR pipe was used to transport the exhaust gas which was mixed with the fresh oxidant. To control the EGR and exhaust flow, butterfly valves were installed at the top opening as a damper to close the exhaust gas flow at a certain ratio for EGR and exhaust out to the atmosphere. High temperature fused silica glass windows were installed to view and capture images of the flame and analyze the flame propagation. The burner simulation shows that MILD combustion was achieved for the oxygen mole fraction of 3-13%. The final design of the burner was fabricated and ready for the experimental validation.

Keywords: Exhaust gas recirculation; computational fluid dynamics; experimental setup; bluff-body MILD burner.