点击切换搜索课件文库搜索结果(990)
文档格式:PDF 文档大小:2.55MB 文档页数:36
Colloidal thrusters are electrostatic accelerators of charged liquid droplets. They were first proposed and then intensively studied from around 1960 to 1975 as an alternative to normal ion engines. Their appeal at that time rested with the large “molecular mass” of the droplets, which was known to increase the thrust density of an ion engine
文档格式:PDF 文档大小:186.29KB 文档页数:8
It is well known that rapidly pulsed current tends to concentrate near the surface of copper conductors forming a “skin”. A similar effect occurs when current flows through a highly conductive and rapidly moving plasma: current tends to concentrate near the entrance and exit of the channel. The reason is the appearance of a strong
文档格式:PDF 文档大小:154.36KB 文档页数:9
The result appears to be trivial, but it is not. Notice that the “velocity increment” ∆V is actually equal to the decrease in orbital velocity. The rocket is pushing forward, but the velocity is decreasing. This is because in a r-2 force field, the kinetic energy is equal in magnitude but of the opposite sign
文档格式:PDF 文档大小:169.65KB 文档页数:12
method was developed by Raschig. Anhydrous hydrazine is a clear, colorless, hygroscopic liquid with an odor similar to that of ammonia. Anhydrous hydrazine is a strong reducing agent and a weak chemical base. Aqueous hydrazine shows both oxidizing and reducing properties. Although potential data show hydrazine
文档格式:PDF 文档大小:135.26KB 文档页数:3
The STAR 13B incorporates the lightweight case developed for the STAR 13 with the propellant and nozzle design of the earlier TE-M-516 apogee motor. The motor case has been stretched 2.2 inches to provide for increased propellant loading. The motor has been used to adjust orbit inclination of a satellite from a Delta launch
文档格式:PDF 文档大小:326.61KB 文档页数:10
Suppose we want to move a satellite in a circular orbit to a position ∆ϑ apart in the same orbit, in a time ∆t (assumed to be several orbital times at least). The general approach is to transfer to a lower (for positive ∆ϑ ) or higher (for ∆ϑ < 0 ) nearby
文档格式:PDF 文档大小:179.79KB 文档页数:13
accelerations account for non-central forces(drag, thrust, etc. X-axis in zenith, y-axis in frames velocity, and z-axis in transverse directions 8 Free orbit solution where 'A and 'B' are lengths and'a andB are phase angles
文档格式:PDF 文档大小:51.09KB 文档页数:7
自动(反馈)控制是几乎所有的飞行器和航空航 天器控制及导航系统的基础。 如果没有反馈控制,人类就不能驾驭很多现代的航空航天工具。 所有现在使用的航天航空工具(如:无人驾驶飞 机,深度空间探测器)都是由反馈控制来导航和 控制的,并且人类可以对其进行高级别监控
文档格式:PPT 文档大小:5.61MB 文档页数:137
1、中华人民共和国民用航空法 2、中华人民共和国飞行基本规则 3、通用航空飞行管制条例 4、国际民航公约附件六 5、CCAR-135 6、CCAR-121 A章 总则 H章 商业非运输运营人的运行合格审定要求 J章 私用大型航空器运营人的运行合格审定要求 K章 航空器代管人的运行合格审定和运行规则 L章 大型和涡轮动力多发动机飞机 M章 农林喷洒作业飞行 N章 旋翼机机外载荷作业飞行 O章 超轻型飞行器 P章 跳伞
文档格式:PDF 文档大小:84.59KB 文档页数:3
发动机总体结构通常可分为转子、静子与附件及其传动三大部份。发动 机(转子)的支承就是指转子向静子传递负荷的必经的关键部位,也是发动机 的最薄弱环节之一。显然,它的布局(方案)对发动机总体结构至关重要
首页上页9293949596979899下页末页
热门关键字
搜索一下,找到相关课件或文库资源 990 个  
©2008-现在 cucdc.com 高等教育资讯网 版权所有