Numerical Simulation And Experimental Study On Low Calorific Value Coal Mine Methane Burner

Calorific value of coal bed methane that contains 30% methane concentration is lower. Studying and exploiting a special burner suit for burning this coal bed methane efficiently and cleanly is endowed with good economic, social and environmental benefit for relieving energy sources intensity, controlling coal bed gas pollution and utilizing coal bed gas sources reasonably.The full size three-dimensional combustion numerical simulation and experimental study on three low calorific value coal bed methane burners are conducted. The changing rules of burner structure and heat load on flowing and burning characteristic of burner are predicted in numerical simulation. The changing rules of burner structure and load on the interior flowing resistance of burner are studied in cool state experiment. The changing rules of burner structure and heat load on flame characteristic and temperature distribution in burning region are investigated in heat state experiment.Adopting Realizable k-εturbulent model, species transport model, eddy dissipation model and P-1 radiation heat transfer model to simulate burning of burner, the results show that burning efficiency of premixed and part-premixed burner reach 99.99%, diffusion burner is lowest. For part-premixed burner, burning temperature is high and distribution of high temperature region of is most extensive, jet flow rigidity is fine, attenuation of velocity is slow, diameter of mainstream are smallest. For premixed burner, burning temperature is highest, combustion focuses in the interior of spout mainly, and influence of swirling jet flow on mainstream is great. For diffusion burner, burning temperature is lowest, attenuation of velocity is quick. Burning efficiency of part-premixed and premixed burner are higher when adopt gradually enlarge spout. Burning efficiency of diffusion burner is higher when adopt gradually shrink spout. Synthetic performance of part-premixed burner is fine. Further numerical simulation research on burning efficiency of part-premixed burner with different spout angle is conducted. The results predict that burning efficiency of this burner is highest when spout diffusive angle amounts 6.87°.The results of cool state experiment indicate that interior flowing resistance of premixed burner is largest and diffusion burner is least. Interior flowing resistance characteristic of part-premixed and diffusion burner are nearly identical with the change of load. The results of heat state burning experiment show that three burners can burn...