• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>A safer space for a safer world >DEBRISK, A TOOL FOR RE-ENTRY RISK ANALYSIS
【24h】

DEBRISK, A TOOL FOR RE-ENTRY RISK ANALYSIS

机译：债务，重新进入风险分析的工具

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

An act of French parliament, adopted in 2008, imposesrnsatellite constructors to evaluate the end-of-lifernoperations in order to assure the risk mitigation of theirrnsatellites. One important element in this evaluation isrnthe estimation of the mass and impact energy of thernsatellite debris after atmospheric re-entry. For thisrnpurpose, CNES has developed the tool DEBRISK whichrnallows the operator to simulate the re-entry phase and tornstudy the demise altitudes or impact energy of thernindividual fragments of the original satellite.rnDEBRISK is based on the so called object basedrnapproach. Using this approach, a breakup altitude isrnassumed where the satellite disintegrates due to thernpressure loads. This altitude is typically around 78 km.rnAfter breakup, the satellite structure is modelled by arnparent-child approach, where each child has its birthrncriterion. In the simplest approach the child is born afterrndemise of the parent object. This could be the case of anrnobject A containing an object B which is in the interiorrnof object A and thus not exposed to the atmosphere.rnEach object is defined by:rn1. its shape, attitude and dimensions,rn2. the material along with their physical propertiesrn3. the state and velocity vectors.rnThe shape, attitude and dimensions define thernaerodynamic drag of the object which is input to thern3DOF trajectory modelling.rnThe aerodynamic mass used in the equation of motion isrndefined as the sum of the object's own mass and thernmass of the object's offspring.rnA new born object inherits the state vector of the parentrnobject.rnThe shape, attitude and dimensions also define thernheating rates experienced by the object. The heating raternis integrated in time up to the point where the meltingrntemperature is reached. The mass of melted material isrncomputed from the excess heat and the materialrnproperties. After each step the amount of ablatedrnmaterial is determined using the lumped mass approachrnand is peeled off from the object, updating mass andrnshape of the ablated object.rnThe mass in the lumped mass equation is termedrn'thermal mass' and consists of the part of the object thatrnis exposed to the flow (so excluding the mass of therncontained children).rnA fair amount of predefined materials is implemented,rnalong with their thermal properties. In order to allow thernusers to modify the properties or to add new materials,rnuser defined materials can be used. In that case thernproperties such as specific heat, emissivity andrnconductivity can either be entered as a constant or asrnbeing temperature dependent by entering a table.rnMaterials can be derived from existing objects, which isrnuseful in case only one or few of the material propertiesrnchange.rnThe code has been developed in the Java language,rnbenefitting from the object oriented approach.rnMost methods that are used in DEBRISK to computerndrag coefficients and heating rates are based onrnengineering methods developed in the 1950 to 1960’s,rnwhich are used as well in similar tools (ORSAT,rnSESAME, ORSAT-J, …). The paper presents a set ofrncomparisons with literature cases of similar tools inrnorder to verify the implementation of those methods inrnthe developed software.
机译：法国议会于2008年通过了一项法案，要求卫星制造商对生命周期终止进行评估，以确保减轻其卫星的风险。评估的一个重要因素是估算大气再进入后卫星碎片的质量和撞击能量。为此，CNES开发了DEBRISK工具，使操作员能够模拟重入阶段并研究原始卫星单个碎片的消亡高度或撞击能量。DEBRISK基于所谓的基于对象的方法。使用这种方法，可以得出一个破裂高度，在此情况下，卫星会由于压力负荷而分解。该高度通常约为78公里。分手后，卫星结构通过孩子/儿童方法建模，其中每个孩子都有其出生准则。在最简单的方法中，孩子是在父对象消灭之后出生的。可能是这样的情况：对象A包含对象B，该对象B位于内部对象A中，因此没有暴露在大气中。每个对象由rn1定义。它的形状，姿态和尺寸，rn2。材料及其物理性质rn3。状态和速度矢量.rn的形状，姿态和尺寸定义了输入到3DOF轨迹建模中的物体的热力学阻力.rn在运动方程式中使用的空气动力学质量被定义为物体自身质量和物体后代质量的总和。 .rn一个新生对象继承了父对象的状态向量。rn的形状，姿态和尺寸还定义了对象经历的加热速率。加热速率随时间累计直至达到熔化温度。从多余的热量和材料特性中计算出熔化材料的质量。每个步骤之后，使用集总质量方法确定烧蚀材料的量，并从对象上剥离，更新烧蚀对象的质量和形状。集总质量方程式中的质量称为“热质量”，由对象的一部分组成那些暴露在水流中的热量（因此不包括被收容孩子的体重）。rn实施了很多预定义的材料，以及它们的热性能。为了允许用户修改属性或添加新材料，可以使用用户定义的材料。在这种情况下，可以通过输入表格将诸如比热，发射率和导热率之类的属性作为常数输入，也可以根据温度来确定温度。rn可以从现有对象派生材料，这在仅一种或几种材料特性发生变化的情况下是无用的。已经用Java语言开发，得益于面向对象的方法。在DEBRISK中用于计算机计算系数和加热速率的大多数方法都是基于1950到1960年代开发的工程方法，并且在类似的工具（ORSAT， rnSESAME，ORSAT-J，...）。本文提出了一系列与同类工具案例的比较，以验证所开发软件中这些方法的实现。

著录项

  • 来源
  • 会议地点 Versailles(FR)
  • 作者

    Pierre Omaly; Martin Spel;

  • 作者单位

    CNES Toulouse 18 av Edouard Belin 31401 Toulouse cedex 9, Email: pierre.omaly@cnes.fr;

    R.TECH, ,H?tel d’Entreprise Parc Technologique Delta Sud, martin.spel@rtech.fr;

  • 会议组织
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号