头部钝度和尾部形状对空射火箭气动特性的影响

头部钝度和尾部形状对空射火箭气动特性的影响

张艳华1,李华星1,张登成2,屈亮2,郑无计2

(1.西北工业大学 航空学院,西安 710072;2.空军工程大学 航空航天工程学院,西安 710038)

摘要:为了研究空中发射运载火箭外形对气动特性的影响规律,通过低速风洞实验,利用六分量天平测量空射火箭模型在迎角0～80°,4个速度(17 m/s,25 m/s,35 m/s,40 m/s)下的气动力和气动力矩。结果表明:在零侧滑条件下,模型的背风区出现了非对称涡,产生较大的侧力和偏航力矩,俯仰力矩随迎角的变化存在不稳定区域;相比圆柱形尾部模型,收敛扩张形尾部提高了模型的纵向稳定性,6%头部钝度的圆头模型最大侧力减少至少50%,非对称涡的起始迎角提高了7°。研究结果可为内装式空射火箭的外形设计提供一定的参考。

关键词:空中发射;运载火箭;大迎角;非对称涡;头部钝度;气动特性

收稿日期:2013-05-29

基金项目:国家自然科学

作者简介:张艳华(1979- ),女,讲师,博士研究生,研究方向为飞行力学和飞行仿真。E-mail:angle0725@hotmail.com。

中图分类号:V211.7文献标识码:A

EffectofNoseBluntnessandDifferentAfterbodyonAerodynamic

CharacteristicsofAir-launchedRocketModel

ZHANGYan-hua1,LI Hua-xing1,ZHANG Deng-cheng2,QU Liang2,ZHENG Wu-ji2

(1.SchoolofAeronautics,NorthwesternPolytechnicalUniversity,Xi’an710072China;

2.CollegeofAerospaceEngineering,AirForceEngineeringUniversity,Xi’an710038China)

Abstract:To study the rule of different shape affecting the aerodynamic characteristics of air-launched rocket,the experiments in low-speed wind tunnel were carried out at the angle of incidence range of 0-80° and the speed of 17 m/s,25 m/s,35 m/s and 40 m/s.Forces and moments were measured through six-component balance.The result shows that vortex asymmetry appears under the conditions of zero side slip.Asymmetrical phenomenon leads to larger side force and yaw moment.In addition,variation of the pitching moment with angle of attack shows instability at some incidences.The longitudinal stability of the model with convergent-expanded afterbody is improved compared to cylindrical afterbody.The maximum side force of the blunt nose model with 6% bluntness is reduced at least by 50%,and the onset angle for vortex asymmetry is increased by 7°.The results offer some references for designing the cabin air-launched rocket.

Keywords:air-launch;carrierrocket;largeangleofattack;asymmetryvortex;nosebluntness;aerodynamiccharacteristics

相比地面发射,空中发射[1-2]具有快速、灵活、可靠、廉价等诸多优点,是一种新型高效的发射方式。内装式空中发射技术[3-4]是将运载火箭内置于运输机货舱内,飞行到一定高度、一定速度后释放火箭,火箭在自身重力、空气动力和稳定伞拉力的综合作用下调整姿态达到点火状态,进行发射。该分离方案对载机改动少,气动干扰小,易于隐身,运载效率较高,目前美国已经利用C-17运输机成功进行了3次模拟内装式空投试验。……