内混音速空气雾化重油喷嘴的试验研究

EXPERIMENTAL STUDY ON INTERNAL MIXING SONIC FLOW AIR BLAST ATOMIZER FOR HEAVY OILS

在横向气流中直射喷嘴雾化研究及超音速气流中喷嘴雾化研究的基础上,针对工业窑炉中烧嘴以重油(通常为油渣)工作的问题,设计和试验研究了内混音速气流两次空气雾化重油喷嘴,从原理上解决了喷嘴雾化细度(燃烧完全)和火焰长度(刚性)之间的矛盾。文中得出合理选择这种喷嘴的结构形式、几何尺寸以及混合腔压力,同时得出很好的雾化细度以及要求的火焰长度。结果表明,混合腔压力与供气压力之比应在0.60～0.70之间,所需压缩空气的压力为0.4MPa,所设计的喷嘴已投入使用。

Based on the experiences previously obtained from the experimental study of plain jet atomizotion under cross flowing air stream and under supersonic air flow,the authors designed and studied an internal mixing sonic flow air blast atomizers for heavy oil application.The contradiction between the requirements for fine spray(for high combustion completeness)and for long flame(for flame rigidity) often existing in industrial furnaces has been solved.Good data were obtained which can be used for the design of such kind atomizers.By properly choosing the configuration and geometrical dimensions of the atomizer,as well as choosing suitable values for mixing chamber pressure,air-liquid ratio,it is possible to have very fine spray and desirable flame length.The results showed that the ratio of mixing chamber pressure to air supply pressure should be in the range of 0.6 to 0.7.For atmospheric pressure combustion furnaces,such air blast atomizer needs 0.4MPa compressed air to create sonic flow at nozzle exit.This type of air blast atomizer has already been put into industrial operation.