固体火箭发动机装药的计算机辅助设计

本文提出了面向微型计算机的计算机辅助设计方法和程序,包括装药几何计算、内弹道性能计算及强度校核图形显示等一体化设计的计算机程序.目前已开发了三维翼柱型装药的模块化结构程序分支,可在微机PC-286/386上进行.本程序通用性广,精度高,可以很方便地扩充到其他药型.     

Index allocation for a reusable LOX/CH4 rocket engine

Reusable rocket engines are the core components of reusable launch vehicles, and have thus become a major focus of aerospace engineering research in recent years. In practice, subsystem design is based on the overall index allocation of an engine; therefore, a multidisciplinary optimization approach is necessary. In this study, design of a reusable methane/liquid oxygen (LOX/CH4) rocket engine with a gas generator cycle was investigated using multidisciplinary optimization. Two parameters were chosen as design variables: pressure and fuel mix ratio of the main combustion chamber. Optimization objectives were specific impulse, structural mass, and life cycle cost of the reusable rocket engine, and constraints were assigned to each discipline according to rocket design requirements. Then, an optimization model was developed, and optimal design parameters were acquired for the LOX/CH4 rocket engine. The proposed method is effective for designing the index allocation of reusable rocket engines and takes into account the multidisciplinary nature of complex systems.     

非线性主轴降维映射法在固体火箭发动机设计优化中的应用

为在二维或三维空间中表达固体火箭发动机高维设计空间,引入非线性主轴降维映射法对多维非线性设计优化问题进行降维处理。以某大型固体火箭发动机设计问题为例,将10变量4有效约束优化问题降维映射到二维空间进行研究,拟合的非线性主轴降维映射模型中,目标函数和约束函数的相对误差控制在1.5%以内。研究表明,非线性主轴降维映射法具有发现多变量非线性优化数学模型本征特性的特点,能对设计变量重要性排序;通过降维展示设计空间全景,为优化算法和优化初始点优选提供了直观、有力的工具;优化轨迹实时展示为优化算法性质研究及算法切换提供了依据;根据优化轨迹从优化结果在降维空间中的位置能够判断优化结果是否具有全局最优解特性。     

固体火箭发动机装药寿命预示方法试验研究

研究了固体火箭发动机装药硬度和ＨＴＰＢ推进剂方坯硬度、强度及延伸率在贮试期内的变化规律，建立了装药硬度－强度、延伸率－贮存期相关联的数学模型和回归方程组。用其预估固体发动机装药寿命。     

两级固体火箭联合动力装置的参数优化

本文针对某型导弹由两级固体火箭发动机组成的联合动力装置进行九变量寻优计算.通过采用二维抛物线插值方法及合理组织迭代的技巧,解决了庞大的目标函数计算子程序耗时太多的问题;经大量调试,协调寻优步长、罚因子、收敛精度,最后成功地完成了本文的九维寻优计算,得到了能稳定收敛的最优解.所得最优方案比原参考方案的发动机总重减轻7.03kg(约占总重的2%).     

A Hybrid Optimization Approach for SRM FINOCYL Grain Design

This article presents a method to design and optimize 3D FINOCYL grain （FCG） configuration for solid rocket motors （SRMs）. The design process of FCG configuration involves mathematical modeling of the geometry and parametric evaluation of various independent geometric variables that define the complex configuration. Virtually infinite combinations of these variables will satisfy the requirements of mass of propellant, thrust, and burning time in addition to satisfying basic needs for volumetric loading fraction and web fraction. In order to ensure the acquisition of the best possible design to be acquired, a sound approach of design and optimization is essentially demanded. To meet this need, a method is introduced to acquire the finest possible performance. A series of computations are carried out to formulate the grain geometry in terms of various combinations of key shapes inclusive of ellipsoid, cone, cylinder, sphere, torus, and inclined plane. A hybrid optimization （HO） technique is established by associating genetic algorithm （GA） for global solution convergence with sequential quadratic programming （SQP） for further local convergence of the solution, thus achieving the final optimal design. A comparison of the optimal design results derived from SQP, GA, and HO algorithms is presented. By using HO technique, the parameter of propellant mass is optimized to the minimum value with the required level of thrust staying within the constrained burning time, nozzle and propellant parameters, and a fixed length and outer diameter of grain.     

Effect of Variable Selection on Multidisciplinary Design Optimization： a Flight Vehicle Example

Different multidisciplinary design optimization (MDO) problems are formulated and compared. Two MDO formulations are applied to a sounding rocket in order to optimize the performance of the rocket. In the MDO of the referred vehicle, three disciplines have been considered,which are trajectory, propulsion and aerodynamics. A special design structure matrix is developed to assist data exchange between disciplines. This design process uses response surface method (RSM) for multidisciplinary optimization of the rocket. The RSM is applied to the design in two categories: the propulsion model and the system level. In the propulsion model, RSM deter-mines an approximate mathematical model of the engine output parameters as a function of design variables. In the system level, RSM fits a surface of objective function versus design variables. In the first MDO problem formulation, two design variables are selected to form propulsion discipline. In the second one, three new design variables from geometry are added and finally, an optimization method is applied to the response surface in the system level in order to find the best result. Application of the first developed multidisciplinary design optimization procedure increased accessible altitude (performance index) of the referred sounding rocket by twenty five percents and the second one twenty nine.     

固体火箭发动机比冲预示经验法

本文简要地评述了国内外固体火箭发动机比冲预示方法.在Landsbaum法的基础上,根据国内外44种不同类型的发动机地面和高空模拟热试车试验统计,利用多维回归分析方法,得出了适合于国内发动机的经验比冲效率参数相关法.这种方法的优点是比冲预示结果比较准确,方法简单,利用袖珍式计算器可快速计算,对固体发动机总体方案论证及性能最优化设计是很有用的.     

翼柱形固体火箭发动机的优化设计

优化设计是固体火箭发动机CAD的重要环节,其优化设计是按照导弹的总体提出的战术和技术要求,朝着一定的设计目标经过多次的方案计算而选出的最佳参数。在已有的优化设计中常避开燃面计算,而计算一些简单形状的药柱(一维或二维)进行优化,因而不能适应目前广泛使用的三维空间。本文对翼柱形固体火箭发动机优化设计进行研究,以发动机的质量比冲为衡量标准,并进行了实例计算,结果令人满意。     

基于多目标遗传算法的大型客机总体参数优化

在大型客机总体参数设计的基础上,提出总体参数优化的问题。建立多目标优化的数学模型,采用多目标遗传算法对大型客机的总体参数进行优化设计。考虑只对一个目标函数进行优化的单目标优化问题,设计程序进行单目标优化的计算。比较单目标优化和多目标优化的结果,分析两种优化方法的差异。算例表明,采用单目标优化在提升优化目标性能的同时会牺牲其他目标函数的总体性能,而多目标优化能兼顾各个目标函数的需求,并使整体达到最优。     

Multidisciplinary Design and Optimization of Multistage Ground-launched Boost Phase Interceptor Using Hybrid Search Algorithm

This article proposes a multidisciplinary design and optimization (MDO) strategy for the conceptual design of a multistage ground-based interceptor (GBI) using hybrid optimization algorithm, which associates genetic algorithm (GA) as a global optimizer with sequential quadratic programming (SQP) as a local optimizer. The interceptor is comprised of a three-stage solid propulsion system for an exoatmospheric boost phase intercept (BPI). The interceptor's duty is to deliver a kinetic kill vehicle (KKV) to the optimal position in space to accomplish the mission of intercept. The modules for propulsion, aerodynamics, mass properties and flight dynamics are integrated to produce a high fidelity model of the entire vehicle. The propulsion module comprises of solid rocket motor (SRM) grain design, nozzle geometry design and performance prediction analysis. Internal ballistics and performance prediction parameters are calculated by using lumped parameter method. The design objective is to minimize the gross lift off mass (GLOM) of the interceptor under the mission constraints and performance objectives. The proposed design and optimization methodology provide designers with an efficient and powerful approach in computation during designing interceptor systems.     

Design and Optimization of 3D Radial Slot Grain Configuration

Upper stage solid rocket motors (SRMS) for launch vehicles require a highly efficient propulsion system. Grain design proves to be vital in terms of minimizing inert mass by adopting a high volumetric efficiency with minimum possible sliver. In this article, a methodology has been presented for designing three-dimensional (3D) grain configuration of radial slot for upper stage solid rocket motors. The design process involves parametric modeling of the geometry in computer aided design (CAD) software through...     

单室双推力固体火箭发动机两级推力的最佳选择

从理论上探讨了单室双推力固体火箭发动机中影响其两级推力的主要因素。建立了导弹/发动机一体化设计的优化模型,对一种推进剂实现双推力,双燃速推进剂实现双推力两种情况分别进行了计算和分析。求出了使导弹射程达到最大,又能够在设计中实现的最佳推力方案。     

导弹/固体火箭发动机一体化设计

本文以两级推力固体火箭发动机为动力的某空-空导弹作为算例,研究了导弹/固体火箭发动机一体化设计的问题.为此,建立了固体火箭发动机的能量模型、质量模型和导弹与目标的数学模型.利用优化理论,成功地完成了九个设计变量的优化问题.优化结果表明,导弹的起飞质量减轻23.3kg(约占总重的9%).     

图形变形法在固体火箭发动机设计优化中的应用

采用图形变形法分析了固体火箭发动机设计优化模型中各设计变量对目标函数和约束的影响程度，探索了可行设计空间，通过显示优化结果点附近设计空间形态定性分析了优化结果鲁棒性。结果表明，图形变形法处理固体火箭发动机设计优化多变量分析及显示问题简单、直观，易于工程应用。     

固体火箭发动机多弧形孔装药设计研究

为弥补现有单室双推力固体火箭发动机装药结构的不足,提出一种由一个中心圆孔和多个弧形内孔组成的新型单室双推力多弧形孔装药结构。该结构包含7个可控结构参数。导出了药柱燃烧周长及通气面积随燃烧肉厚变化规律的计算公式;利用火箭发动机设计结构,分析了不同参数下多弧形孔装药结构的内弹道特性;在相同技术要求下,对比了多弧形孔装药和双药型装药结构的内弹道特性参数。设计及计算结果表明,新型多孔装药结构易实现单室双推力的要求,在文中所取算例下,采用多弧形孔装药的导弹相比采用星孔-单孔管型药柱装药的导弹加速时间缩短75%,导弹最高速度提高17%,且导弹速度和推力都更加稳定。多弧形孔装药结构为单室双推力火箭发动机设计提供了一种新的技术途径。     

固体火箭发动机三维药柱燃面自动化设计方法研究

提出了一种三维药柱燃面自动化设计的新方法：根据设计者输入的设计指标和全局参数值,自动确定一系列药柱结构可选方案,自动对每一个结构方案进行药形几何参数的优化设计,自动对结构方案进行优选,并确定出可行的药柱设计方案,输出燃面设计结果。经实例设计,表明该方法是切实可行的。     

多学科设计优化在非常规布局飞机总体设计中的应用

以飞翼布局飞机总体设计为例,展示如何将多学科设计优化(MDO)方法有效地应用于非常规布局飞机总体设计.基于二级优化方法,提出一种飞机总体MDO实施流程.该流程包括系统级优化、子系统级优化(或评估)和多学科模型生成器3个部分.系统级优化的任务是优化全局设计变量,使系统目标最优.子系统级优化涉及的学科包括气动、隐身、结构、...     

装药几何参数不确定性优化设计

1引言固体火箭发动机装药设计,一般要求在满足发动机内弹道性能和相关约束条件下,选择药型并确定其几何参数,同时综合考虑燃烧室壳体内部绝热层、衬层和人工脱粘层的设计要求。装药设计作为发动机设计的核心,其设计质量很大程度决定了发动机性能优劣。航天飞机固体助推火箭发动     

端面燃烧固体火箭发动机的爆炸问题研究

本文论述了端面燃烧固体火箭发动机的爆炸问题,总结和分析了端面燃烧固体火箭发动机产生爆炸的重要原因.实验表明:在选择端面燃烧装药的初始增面率时,采用木制假药柱和推进剂短药柱构成的装药会给实验结果带来很大的偏差,导致选出不合适的初始增面率,把它应用在相同尺寸的固体推进剂端面燃烧药柱中时,将会引起发动机产生爆炸.