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本帖最后由 firexl 于 2013-6-30 13:28 编辑
说到客机和温度的关系，就不能不提协和号。作为一架速度超过2马赫的客机，温度的问题显得尤为突出。以下文字来自wikipedia，节选趣闻如下：
1，全速飞行时鼻尖温度127度，这是铝材能长期承受的最高温度
2，协和号的最大飞行速度由以上温度决定
3，由于受热膨胀，全速飞行的时候比停在地面上的时候长33厘米
4，在协和号做最后一次超音速飞行的时候，机械师们会把帽子塞到控制台和机头的空隙里，这样降落之后帽子就会永久地嵌在那个地方
5，在高空中其他飞机需要给客舱加热，而协和号则要给客舱降温
6，几乎所有的协和号都涂成白色，这是为了反射阳光从而降温
7，法航曾经为了给pepsi打广告把一架协和涂成pepsi的颜色，代价就是要缩短连续的2马赫飞行时间
Air friction on the outer surfaces caused the cabin to heat up during flight. Every surface, such as windows and panels, was warm to the touch by end of the flight.[58] Besides engines, the hottest part of the structure of any supersonic aircraft, due to aerodynamic heating, is the nose. The engineers used Hiduminium R.R. 58, an aluminium alloy, throughout the aircraft due to its familiarity, cost and ease of construction. The highest temperature that aluminium could sustain over the life of the aircraft was 127 °C (261 °F), which limited the top speed to Mach 2.02.[59] Concorde went through two cycles of heating and cooling during a flight, first cooling down as it gained altitude, then heating up after going supersonic. The reverse happened when descending and slowing down. This had to be factored into the metallurgical and fatigue modelling. A test rig was built that repeatedly heated up a full-size section of the wing, and then cooled it, and periodically samples of metal were taken for testing.[60][61]
Owing to air friction as the plane travelled at supersonic speed, the fuselage would heat up and expand by as much as 300 mm (almost 1 ft). The most obvious manifestation of this being a gap that opened up on the flight deck between the flight engineer's console and the bulkhead. On some aircraft that conducted a retiring supersonic flight, the flight engineers placed their caps in this expanded gap, wedging the cap when it shrank again.[62] To keep the cabin cool, Concorde used the fuel as a heat sink for the heat from the air conditioning.[63] The same method also cooled the hydraulics. During supersonic flight the surfaces forward from the cockpit became heated, and a visor was used to deflect much of this heat from directly reaching the cockpit.[64]
Concorde had livery restrictions; the majority of the surface had to be covered with a highly reflective white paint to avoid overheating the aluminium structure due to heating effects from supersonic flight at Mach 2. The white finish reduced the skin temperature by between six to 11 degrees Celsius.[65] In 1996, Air France briefly painted F-BTSD in a predominantly blue livery, with the exception of the wings, in a promotional deal with Pepsi.[66] In this paint scheme, Air France were advised to remain at Mach 2 for no more than 20 minutes at a time, but there was no restriction at speeds under Mach 1.7. F-BTSD was used because it was not scheduled for any long flights that required extended Mach 2 operations. |
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发表于 2013-6-30 11:05
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提升卡
变色卡
千斤顶
发表于 2013-6-30 11:18
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