The Study On Structural Optimization And Heating Uniformity Of Atmospheric Gas Burner

With the development of clean energy,natural gas has increasing proportion in Chinese primary energy consumption annually.Urban gas accounts for the highest ratio of Chinese natural gas consumption,which is the main part for the growth of natural gas consumption.Meanwhile,natural gas which is consumed by domestic gas stoves takes an important part in the consumption of urban gas.Actually,the common gas stove is atmospheric gas stove.However,millions of gas stoves are produced with low efficiency.Thus,it is the key to improve the efficiency of domestic gas stoves.Besides,heating uniformity is essential for the usage of gas stove.In this research,thermal efficiency,CO emission and heating uniformity are regarded as standards to judge the performance of atmospheric gas burner.And there are three parts which are the structural optimization of ejector and the study on gas distribution in the outlet of flame ports,the structural optimization of gas burner based on heat transfer analysis,heating uniformity analysis based on thermal infrared imaging technology.Firstly,this part focuses on structural optimization of the entrance of primary air and the nozzle of ejector which have an effect on the performance of ejector by experimental method and numerical simulation.The results show that the performance of ejection becomes worse with the increase of axial distance of nozzle.Besides,the four-part entrance has better performance than the two-part one except the opening of 50%.Besides,the gas flow rate is not uniform at the outlet of flame port.Then,this part studies on heating height and the height on inner burner which have an influence on thermal efficiency and heating transfer process of gas stove.The results indicate that the optimal heating height is 30.5mm.The key factor that affects convective heat transfer coefficient is fluid velocity.Furthermore,the variation of the height of the inner burner has an effect on whole combustion zone.Finally,based on thermal infrared imaging technology,the structure of gas burner is studied which affects heating uniformity.The results show that the temperature of inner heating area increases with the increase of the height of the inner burner,while the temperature of inner heating area decreases with the decrease of inner diameter of inner burner.With the increase of heating height,the temperature of inner and outer heating areas declines.The heating zone of outer ring has better heating uniformity than that of the inner ring.Both of heating zones have obvious effects on heating uniformity of the whole heating zone.In this research,thermal efficiency has increased by 2.2% and heating uniformity has improved through the structural optimization of inner burner.