推进技术
推進技術
추진기술
JOURNAL OF PROPULSION TECHNOLOGY
2015年
4期
532-539
,共8页
战术发动机%中%小过载%两相流%三维数值仿真
戰術髮動機%中%小過載%兩相流%三維數值倣真
전술발동궤%중%소과재%량상류%삼유수치방진
Tactical solid rocket motor%Low and medium acceleration%Two-phase flow%Three-dimensional numerical simulation
针对战术发动机的飞行条件,建立了固体发动机过载条件下内流场两相流计算模型,开展了3种典型中、小飞行过载下的流场计算,详细分析了燃烧室内凝相颗粒冲刷参数分布,并初步分析了颗粒聚集状态与绝热层烧蚀之间的关系。研究结果表明:(1)当横向过载达到一定程度,在发动机筒段绝热层表面,在承载面沿着流场方向会形成一条粒子浓度缓慢增大的聚集带,而在非承载面粒子分布较为稀疏。(2)过载大小对颗粒冲刷速度的影响不明显,主要原因是燃气本身对颗粒运动的轴向加速很大,而过载的作用体现不明显。(3)燃烧室中粒子密集区一定程度反映了该部位的烧蚀环境较为严酷,绝热层烧蚀主要由于凝相粒子低速聚集导致了局部热增量加剧并引起了颗粒的二次聚集效应。因此,长时间中、小过载下,为了缓解燃烧室绝热层局部的严酷烧蚀环境,在已知粒子冲刷参数分布下,可增加局部绝热层设计厚度,调整发动机的飞行姿态使承载面呈现正负交替的过载以及增加发动机自身旋转动作。
針對戰術髮動機的飛行條件,建立瞭固體髮動機過載條件下內流場兩相流計算模型,開展瞭3種典型中、小飛行過載下的流場計算,詳細分析瞭燃燒室內凝相顆粒遲刷參數分佈,併初步分析瞭顆粒聚集狀態與絕熱層燒蝕之間的關繫。研究結果錶明:(1)噹橫嚮過載達到一定程度,在髮動機筒段絕熱層錶麵,在承載麵沿著流場方嚮會形成一條粒子濃度緩慢增大的聚集帶,而在非承載麵粒子分佈較為稀疏。(2)過載大小對顆粒遲刷速度的影響不明顯,主要原因是燃氣本身對顆粒運動的軸嚮加速很大,而過載的作用體現不明顯。(3)燃燒室中粒子密集區一定程度反映瞭該部位的燒蝕環境較為嚴酷,絕熱層燒蝕主要由于凝相粒子低速聚集導緻瞭跼部熱增量加劇併引起瞭顆粒的二次聚集效應。因此,長時間中、小過載下,為瞭緩解燃燒室絕熱層跼部的嚴酷燒蝕環境,在已知粒子遲刷參數分佈下,可增加跼部絕熱層設計厚度,調整髮動機的飛行姿態使承載麵呈現正負交替的過載以及增加髮動機自身鏇轉動作。
침대전술발동궤적비행조건,건립료고체발동궤과재조건하내류장량상류계산모형,개전료3충전형중、소비행과재하적류장계산,상세분석료연소실내응상과립충쇄삼수분포,병초보분석료과립취집상태여절열층소식지간적관계。연구결과표명:(1)당횡향과재체도일정정도,재발동궤통단절열층표면,재승재면연착류장방향회형성일조입자농도완만증대적취집대,이재비승재면입자분포교위희소。(2)과재대소대과립충쇄속도적영향불명현,주요원인시연기본신대과립운동적축향가속흔대,이과재적작용체현불명현。(3)연소실중입자밀집구일정정도반영료해부위적소식배경교위엄혹,절열층소식주요유우응상입자저속취집도치료국부열증량가극병인기료과립적이차취집효응。인차,장시간중、소과재하,위료완해연소실절열층국부적엄혹소식배경,재이지입자충쇄삼수분포하,가증가국부절열층설계후도,조정발동궤적비행자태사승재면정현정부교체적과재이급증가발동궤자신선전동작。
According to the flight conditions of the tactical SRM(Solid Rocket Motor),a three-dimensional numerical model of two-phase flow was established for overload conditions. Flow field calculations were carried out for three different types of working conditions under small and medium-sized overload,respectively. The pa?rameter distribution of the condensed particles in combustion chamber was analyzed,and a preliminary analysis of the effects of aggregation state of particles on the insulation ablation was performed. The results show that:(1) When the lateral acceleration is larger than a certain degree,an accumulation belt will be formed on the cylin?der section of the motor insulator surface as particle concentration increasing slowly on the bearing surface along flow direction. However,particle distribution is sparse on the non-bearing surface. (2)The contribution of mo?tor overload on the particle velocities is not significant. The main reason is that the axial acceleration of particles is mainly derived from the gas itself.(3)To some extent,particle aggregation zone shows the position of relative?ly severe ablation environment in the combustion chamber of motor. The insulation ablations mainly due to the low velocities of particles aggregation lead to the increasing of heat increment on the local insulator surface , and cause particles focalized secondly. Thus,under low and medium acceleration with long operation time,in or?der to alleviate the harsh ablation environment of local insulator in chamber combustion,according to the known particle distribution parameters,the design of motor should increase the thickness of local insulator,and adjust the flying attitude to make the bearing surface rendering acceleration alternating and increase the rotation action of motor.