含硼推进剂固冲发动机补燃室内凝聚相燃烧产物特性试验研究

Experimental investigation on particularity of condensed combustion products of boron-based propellant in secondary combustion chamber of solid propellant ramjet

针对含硼贫氧推进剂固体火箭冲压发动机,提出了一种补燃室内凝聚相燃烧产物取样和分析方法,基于设计的水冷探针取样装置,通过地面直连式试验对发动机中间燃烧产物进行了采集.试验证明,该方法能够有效开展含硼推进剂固冲发动机补燃室内凝聚相产物取样研究,并使用现代仪器手段对产物的理化特性与粒度分布规律进行了深入分析.研究结果表明,凝聚相产物的形态呈无规则状,大部分颗粒呈片状,只含有少量形状很规则的球状颗粒;产物的主要成分为B2O3;产物的粒度呈三峰分布,主要集中在0.3～40 μm之间.另外,随发动机补燃室长度增加,粒度逐渐减小;自发动机中心轴线位置向发动机壁面位置的径向变化过程中,粒度先明显减小,后略微增大.

A sampling and analysis method for condensed combustion products of boron-based propellant in secondary combustion chamber of solid propellant ramjet was presented.A water cooled sampling system was designed and used to collect the intermediate combustion products in direct-connected test,and the practicability of the sampling system was proved.The particularity of condensed combustion products are determined from statistic and microcosmic aspect by modern devices.The results firstly show that the appearance of particles is irregular,most of particle is sheet,only a few particles are regular sphere.Secondly,the condensed combustion products mainly consist of B2O3.Lastly,the granularity distribution exhibits three peaks between 0.3 μn and 40 μm.In addition,the granularity decreases with increase the length of combustion chamber,whereas decreases appreciably at first,then increases a little finally with radial position changing from center axis to inner wall.