20kW Methane Experimental Research And Numerical Simulation Of Flameless Combustion Characteristics

Flameless combustion compared with conventional combustion pollutants(NOx) emissions are very low and significantly improve the thermal efficiency, environmental protection, conservation of resources has very important significance, is a very good way of burning, this item combustion technology is also known as one of the 21 st century the most promising combustion technology.Research and numerical simulation experiment flameless combustion are very important research method, based on this, this paper designed a high temperature flue gas sampling guns, focus on Test Method flameless combustion and combustion center swirl combustion characteristics, summarized flameless combustion with center swirl combustion compared to the advantages, the results showed that: three water-cooled coaxial TP316 L steel tube sampling gun capable of withstanding temperatures above 1600 K, and can successfully capture the furnace component concentrations. Conventional swirl combustion flame rapidly intense burning beneath the burner, high temperature, resulting in heat-type NOx, burners low oxygen concentration below the high CO concentrations. Flameless combustion of fuel and oxidant are mixed together without fast, so that no area of intense burning, there is no high-temperature region, so that very little heat generation type NOX. In the absence of intense burning areas, oxygen, CO in the furnace were tested diffusion state. In flameless combustion, or if the condition of the furnace, burners are not designed well lead to incomplete combustion of fuel, CO emission is too high. Flameless combustion furnace water-cooled heat exchanger tube asymmetry, then, would flameless combustion of the combustion zone to produce a certain offset, so that the component concentration field uneven.To select flameless combustion simulation model to provide some reference value, studied the accuracy of the simulation model of the numerical simulation results show that: the use of RNG k-? turbulence model and EDC Combustion Model, the temperature, O2 furnace in addition to the distribution of the field inside the jet simulation error several points below the large majority of the simulation error is small. While the analog CO furnace above error is small, the error is below the larger, because while the RNG k-? model has some shortcomings in simulating high intensity turbulent flow turbulence in the vicinity of the water cooling pipes more complex than the rest, is not accurate simulate the turbulent flow field, resulting in lower furnace analog CO inaccurate. In order to more accurately simulate the turbulent flow field, such as large eddy simulation can be more precise turbulence models.