摘要
为初步得出适用于脉冲爆震发动机的喷管设计准则,基于数值模拟和理论分析方法,对脉冲爆震燃烧非稳态排气过程及适用的喷管设计方法进行了分析。脉冲爆震燃烧的非稳态排气过程可分为4个阶段:爆震波传播阶段、压力速降阶段、压力平台阶段和低压排气阶段。以直管中的C_(2)H_(4)/O_(2)脉冲爆震燃烧为例,排气压力在90.6 p_(∞)~1.72 p_(∞)范围内变化,若采用非稳态喷管设计方法,则可调喷管的扩张比对应为13~1。若采用固定型面喷管,则应当尽可能避免过膨胀状态下的激波损失,喷管设计点参数可使用排气压力平台区燃气参数进行计算,推力系数可达到95%左右。固定型面喷管设计点的气体参数对应最后一道泰勒膨胀波传播至出口时的燃气状态参数,可用经典爆震理论公式推导求解,从而实现脉冲爆震燃烧室固定型面喷管的快速设计。
In order to initially derive the nozzle design guidelines for pulse detonation engine,the unsteady exhaust process of pulse detonation combustion and the applicable nozzle design methods were analyzed based on numerical simulation and theoretical analysis methods.The unsteady exhaust process of pulse detonation combustion can be divided into four stages:detonation wave propagation stage,pressure downhill stage,pressure plateau stage and low pressure exhaust stage.Take the pulse detonation combustion of CH/O in straight tube as an example,the expansion ratio of suitable adjustable nozzle changes from 13 to 1 corresponding to the exhaust pressure range from 90.6 pto 1.72 p.For the fixed nozzle scheme,the loss of shock wave triggered by over-expansion should be avoided.The design point of the fixed nozzle can be calculated by making use of the parameters of pressure platform,under which the thrust coefficient up to 0.95.The gas parameters of design point corresponding to the gas state when final Taylor expansion wave travels to the exit,which can be deduced from classical detonation theoretical equation,so as to realize the rapid design of fixed nozzle for the detonation.
作者
王永佳
严宇
焦中天
张扬
范玮
WANG Yongjia;YAN Yu;JIAO Zhongtian;ZHANG Yang;FAN Wei(Science and Technology on Liquid Rocket Engine Laboratory,Xi'an Aerospace Propulsion Institute,Xi'an 710100,China;School of Power and Energy,Northwestern Polytechnical University,Xi'an 710072,China;Xi'an Institute of Modern Control Technology, Xi'an 710054,China)
出处
《火箭推进》
CAS
2021年第6期93-100,共8页
Journal of Rocket Propulsion
基金
国家自然科学基金(51176158,91441201,51376151)
教育部博士点基金(20126102110029)
西北工业大学博士论文创新基金(CX201504)。
