Highly Reliable Plasma Igniter for Ram/Scramjet

用于冲压/超燃冲压发动机的高度可靠的等离子点火器

基本信息

批准号：
10555331
负责人：
MASUYA Goro
金额：
$ 8.51万
依托单位：
Tohoku University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10555331/
关键词：
Scramjet Supersonic Combustion Ignition Plasma Jet 着火・保炎

项目摘要

In order to realize the ramjet/scramjet engine which is one of the most promising candidates of the propulsion system of aerospace planes, reliable ignition of fuel in supersonic airstream is an important subject. Plasma torches have been developed and tested in direct-connect combustors as well as in a sub-scale engine. However, early results of these tests showed insuffficient durability and reliability of the plasma igniter. The present research project has been carried out to clarify the cause of malfunction of the igniter and to develop highly reliable plasma igniter with experimental, theoretical and numerical approaches.The feedstock of the torch was changed from oxygen to nitrogen. Detrition of the electrodes and the nozzle of the torch was significantly suppressed by this change. In addition, the coolant of the torch was changed from gas to water. This change lessened thermal load of the torch. Durability of the plasma torch was greatly improved by these changes.Experimental and theoretical studies confirmed that the ignition performance of the nitrogen torch was as good as that of the oxygen torch. Improvement of the ignition perfomance was achieved by use of nitrogen/hydrogen mixture as the feedstock, though the minimum input power for the torch was increased. The improvement of ignition perfomance was caused by combustion of hydrogen in the plasma jet.When fuel was injected upstream the plasma torch, experiment and numerical simulation showed that it is important to select the lateral and transverse locations of the injector to make collision of the fuel jet and the plasma jet. The streamwise location and the angle of injection showed minor influence. When the fuel was injected downstream the plasma torch, the streamwise location became important, too.Increase of airstream Mach number made ignition performance of the torch worse. The effect of the pressue of the airstream was not straight forward in the present experiment.

为了实现RAMJET/SCRAMJET发动机，这是航空航天飞机推进系统中最有前途的候选者之一，超音速气流中燃料的可靠点火是重要的主题。在直接连接燃烧器以及亚尺度发动机中开发和测试了血管火炬。但是，这些测试的早期结果表明血浆点火器的耐用性和可靠性不足。目前的研究项目是为了阐明点火器故障的原因，并使用实验，理论和数值方法开发高度可靠的等离子体点火器。火炬的原料从氧气更改为氮。电极的逐渐减弱和火炬喷嘴被这种变化显着抑制。此外，火炬的冷却剂从气体更换为水。这种变化减少了火炬的热负荷。这些变化可以极大地提高等离子火炬的耐用性。实验性和理论研究证实，氮割炬的点火性能与氧气火炬的点火性能一样好。通过使用氮/氢混合物作为原料可以提高点火性能的改善，尽管火炬的最小输入功率增加了。点火性能的改善是由氢在等离子体射流中的燃烧引起的。当燃料上游注入等离子火炬，实验和数值模拟时，很重要的是，选择喷油器的横向和横向位置以使燃料射流和等离子体射流碰撞。流向位置和注射角度显示出轻微的影响。当燃料在下游的等离子火炬下面注入时，流式位置也变得很重要。在本实验中，气流新闻界的影响并不直接。