For faster navigation, this Iframe is preloading the Wikiwand page for
黑障區.
黑障區(英語:Blackout zone),是导弹弹头和航天器返回舱等再入体返回大气层时,因再入体表面超高速摩擦形成高温等离子区导致无线电信号衰减至中断的飞行区段。其范围取决于再入体的外形、材料、再入速度,以及发射信号的频率和功率等。黑障现象给载人飞船再入返回时的实时通信、再入测量造成困难。
黑障经常被与热障混淆。黑障指的是,因大气分子与飞行器高速撞击形成包裹飞行器的等离子鞘,产生的反射无线电波的效应,最终导致无线电通讯衰减及中断,并非指热效应;虽然等离子气体同时伴随着热效应和强电场,从载人飞行器的舷窗能看见类似放电的明亮且闪烁的白色眩光,而不是“黑”暗的。因等离子产生的条件苛刻,当飞行器速度降至8-12马赫后,与大气摩擦将不足以形成等离子而是热分子,从载人飞行器的舷窗看见的是炽热空气发出的稳定的暗红光;此时包裹飞行器的只是炽热的空气层,有强烈的热效应却并不影响无线电通讯。视再入大气选择的轨道,在12倍音速以上黑障影响作用明显,无线电通讯困难;在8倍音速以下黑障作用消失,无线电恢复;在8至12马赫的过渡区间,无线电通讯受影响,但也可通过在离子鞘薄弱的位置如飞行器尾部建立通讯,还有使用定向性更强的激光代替无线电波穿透等离子鞘保持通讯的方案。
{{bottomLinkPreText}}
{{bottomLinkText}}
This page is based on a Wikipedia article written by
contributors (read/edit).
Text is available under the
CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.
{{current.index+1}} of {{items.length}}
Thanks for reporting this video!
This browser is not supported by Wikiwand :(
Wikiwand requires a browser with modern capabilities in order to provide you with the best reading experience.
Please download and use one of the following browsers:
An extension you use may be preventing Wikiwand articles from loading properly.
If you're using HTTPS Everywhere or you're unable to access any article on Wikiwand, please consider switching to HTTPS (https://www.wikiwand.com).
An extension you use may be preventing Wikiwand articles from loading properly.
If you are using an Ad-Blocker, it might have mistakenly blocked our content.
You will need to temporarily disable your Ad-blocker to view this page.
✕
This article was just edited, click to reload
Please click Add in the dialog above
Please click Allow in the top-left corner,
then click Install Now in the dialog
Please click Open in the download dialog,
then click Install
Please click the "Downloads" icon in the Safari toolbar, open the first download in the list,
then click Install
{{::$root.activation.text}}
Follow Us
Don't forget to rate us
Oh no, there's been an error
Please help us solve this error by emailing us at
support@wikiwand.com
Let us know what you've done that caused this error, what browser you're using, and whether you have any special extensions/add-ons installed.
Thank you!