Generation Mechanism of Environmental Pollutants in the Frame Integrated Supersonic Nozzle Exhaust

机架一体化超音速喷嘴排气环境污染物产生机理

基本信息

批准号：
07405061
负责人：
NAGASHIMA Toshio
金额：
$ 4.1万
依托单位：
University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07405061/
关键词：
Supersonic Nozzle Stratospheric Flight SCRam Jet Exhaoust Laser Measurment Numerical Simulation DSMC法

项目摘要

Whilst the interest for the faster than supersonic flight is ever increasing amongst those who feel natural to rely upon advanced technology, the world-wide concerns today involve the green house effect and thestratospheric ozone depletion phenomena, which vividly shows a lack of full confidence in our scientific and technological achievements. The environmental effect should be hereafter the first issue to be treated in exploring the developments of new technology.In the present study, the exhaust gas emission from the hydrogen fueled SCRam (Supersonic Combustion Ram) jet engine for HST (HyperSonic Transport) system has been examined. An emphasis is upon the thermo-fluid chemical process to produce pollutants (namely, NOx) at such propulsion system that inevitably operates in the stratospheric atmosphere and possesses a geometrically particular feature of full integration with the vehicle structure.The theoretical part presently treats computational improvements concerning the numerical stiffness due to the chemical reactions involving H-O-N species. The newly developed scheme is coupled with the Navier-Stokes equations of fluid motion to reveal the details of highly reactive SCRam jet external nozzle flows.The experimental part consists of NO gas injection into a space chamber in which the pressure and the Ozone concentration can be adjusted to simulate in the high altitude atmosphere. Flow visualization using schlieren and LIF optical method is employed to examine the injectant shock wave structure, the associated density gradient field and the NO number density distribution, wherefrom the depletion of Ozone due to NO injection is accessed.

尽管对那些自然而然地依靠先进技术的人的兴趣比超音速飞行的速度越来越快，但当今世界范围内的关注涉及温室效应和theStratospheric臭氧灭绝现象，这生动地表明了我们对我们的科学和技术成就缺乏充分的信心。以后的环境效应应在探索新技术的发展时要处理的第一个问题。在本研究中，已经检查了用于HST（超音速运输）系统的氢加油SCRAM（超音速燃烧RAM）喷气发动机的排气排放。强调热流体化学过程是在这种推进系统上产生污染物（即NOX），该系统不可避免地在平流层大气中运行，并具有与车辆结构完全整合的几何特征。理论部分目前既有计算均具有相关的数值僵硬度涉及化学反应而涉及化学反应的物种。新开发的方案与流体运动的Navier-Stokes方程相结合，以揭示高反应性SCRAM喷气式喷嘴流量的细节。实验部分由无气体注入到空间室中，在该空间室中，可以调节压力和臭氧浓度以在高海拔高度大气中进行模拟。使用Schlieren和LIF光学方法的流动可视化来检查注射剂冲击波结构，相关的密度梯度场和无数量密度分布，其中由于未访问注射而导致的臭氧耗尽。