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High-temperature gas is widely used in the steel, cement, and metallurgical industries. The high-temperature gas generator system and industrial furnace have difficulty in using low quality coal in the current situation. According to this situation, the Coal Combustion Laboratory develop the ultra-high temperature gas generator system, which combine the fluidized bed coal gasification and fluidized bed combustion. This paper described its process, and then designed one sleeve burner for this system. The experiment completed the cold model measurement of the flow field on the burner model,and used the engineering software FLUENT to simulate the combustion to meet the needs of rotary kiln production.Low calorific value coal gas burner is one of the key components of ultra-high temperature gas generator system. Due to the system has many equipment and complex process, and the temperature of low calorific value flue gas and oxygen-containing gas were 900℃, it is not suitable to use three-channel or multi-channel burner structure. In order to meet the effects of burning and satisfy safety of the system, the paper designed the sleeve burner with the swirl leaves, and built the whole modeling cold burner measurement system with the cold principles. The experiments used five-hole probe measurement system, and compared the different number,angle,and position of swirl leaves, and different centre wind for swirl export velocity. Experimental tests got various conditions of axial, tangential and radial velocity changes, finally got the different number and position of the swirl blade have most obvious changing to the swirl flow field by the experiment.In the actual working conditions, the combustion of the gas is the important key of the system. Based on the optimal design parameters of the measure flow field and specific project, use Gambit software to finish the three-dimensional modeling and meshing,and use Fluent to simulate combustion characteristics for high temperature gas in a rotary kiln as a combustion chamber, including temperature, velocity and pressure field. Simulated flame temperature get to 1780K, 1503℃; The maximum speed is 194 m/s at the mixed positon of gas and fume at the nozzle exit, with the design value is very close; Some kiln maintained at negative pressure, about -336Pa. The combustion can be simulated by the practical needs of rotary kiln applications.
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