滞止压力为 [tex=3.857x1.0]eiWVvJSsft4UTVGgm6sFvDP/YfCEZ4TuzQxbydKWgH8=[/tex], 滞止温度为 [tex=2.286x1.0]R/11a/zoycK5VajdZOAeORpO+rDjDOS/8DYekMVHh48=[/tex] 的空气可逆绝热流经收缩喷管, 在截面积为 [tex=5.714x1.357]Tm3LtEK7zjydwjJq3p5DQtdwk8iwF5DYgvNhyrJmO1rDSXxGkbUK7iB+Y/5VljCf[/tex]处气流马赫数为 0.6 。若喷管背压力为 [tex=3.857x1.0]7sOU4iLA8zBpRyP+LPOVvGQdRqxQaxbSh2yEQTPZMEU=[/tex], 试求喷管出口截面积

2022-10-30

滞止压力为 [tex=3.857x1.0]eiWVvJSsft4UTVGgm6sFvDP/YfCEZ4TuzQxbydKWgH8=[/tex], 滞止温度为 [tex=2.286x1.0]R/11a/zoycK5VajdZOAeORpO+rDjDOS/8DYekMVHh48=[/tex] 的空气可逆绝热流经收缩喷管, 在截面积为 [tex=5.714x1.357]Tm3LtEK7zjydwjJq3p5DQtdwk8iwF5DYgvNhyrJmO1rDSXxGkbUK7iB+Y/5VljCf[/tex]处气流马赫数为 0.6 。若喷管背压力为 [tex=3.857x1.0]7sOU4iLA8zBpRyP+LPOVvGQdRqxQaxbSh2yEQTPZMEU=[/tex], 试求喷管出口截面积

答案：

 在该截面上,  [tex=7.357x2.214]/xC0HoP1DkaLqmc465IU/R5WE1eFYcLvykYNSidkzDXnzyZILfxbzkoR4pFnTyNZmHwOYqLD7TtMlp/cVHVUCg==[/tex] 而声速 [tex=9.286x2.143]A8JeOBcIIOhbokwbZ6o+p0KI0aA0nqBk+A6Hig89AwYUzTpk2OxaQ5UAySTban5fGo9n5nZ/kAfCgLNqtrBK2A6wDCG06VgRK9RLz0ECH1k=[/tex], 所以己知 [tex=1.5x1.0]aZxeqPls+x6ndZSoQWM/qw==[/tex]即可确定截面上气流温度、流量等参数[tex=11.857x2.714]mBM3Ybq+dHiBLmePBHjFCYTvMgFaqbjYcef0BYbln0aPEwz2fNHqP7h2kuHyVhzUYb8c33owqeyOf7WG3LqqJxIL3jNwNTf1E3QbfrwYiMU=[/tex][tex=34.0x3.0]syteb/Tyyg5n2dUJSa1RDrqPnzIoqiJ573SBWC5FL+Huc229Jlu1zuvWTEONUN5mgDh4pmoG8rXl8+wmFBNJccYqr28rMwdN//EJ3G6kwDIBcOOqGyFG2DD1g1v2zG1dT2RsaTI4jN9iEQiLtS0Eil6LFboGta4URIOAtI5XI5dBpVbXY6ZRhDc9mekExhDB/O4G3EeZRmnL2u+TQmxumTX66ZkwIT7cqD0+veeWtW+rfrHPP5+hxXU7K4+wHtaxiDPLQRL/hfkW+i36sdN4PA==[/tex][tex=21.643x2.429]sU17HN2+LgYgpBq+pFQUtUpPYkEp/gZgz7YOWYsaSbpsrzr4xPIZJzVn5v3atbE/Zajl17LLq5pc7spZnusiwu0mPNf2MjVxC03BHTVhauIVNxjhYEhoyN5iX25HAYUp+x6Ppgv3d6hdz1ownMu1gV5hYd5KaSrTtXqpSEw5SVeup76PY1zuz0ECjoIh6psr[/tex], 所以, [tex=9.286x1.214]6EU2B97/ozzx5qv0m2ASeagc8EvaoAJG6aa9WVegQ42rJ5H0BodBwBrw5d8MHTb6DrnRR96/zcQ2B1FJjd5hxw==[/tex], 而出截面即为临界截面[tex=24.786x2.643]y8xnB4L3lF3aChVfDijBR5xKeOGdM5QilFNZGiK9Uz0yD6QS0H1PePAAK6qCkjd92w7vXOXNg4ZOccUmeVTNqzGrU3YaRWVx6kqj8TGdvIsH6zSqBRApYkrBp/jnUwN5ceyHlOdnlSSKTwuUl+ZSKPhPf5ST6/tKYadRGcaSEhYdtSrEGtWpklMdSia6JFn9V/S5e9jIDvs+BFQ6yD032A==[/tex][tex=13.357x1.571]KwFMN9AIO2S8lPBJ9m4NDRAW7BmohfhWHIqcQb+CCW8Kl0ff4BHHhT9f05PogzBaogSmPGH68bnExn7IFofzfyuzbDw8LQWcQg5XxHZXO7CYw1McmbBK6JcJc/uRpmZ1[/tex], 解得 [tex=12.071x2.286]9r53az1TCUhSG9DNKjL0/sfjFJyozU/7AVbIMU9butfgIJi6E6+P914cV/rF3XNws/HAC5dcDXy0Ouc8AMDtb7/Cv90jlwmaTbMfyVGmYP4=[/tex]

举一反三

内容

0
6个顶点11条边的所有非同构的连通的简单非平面图有[tex=2.143x2.429]iP+B62/T05A6ZTM0eeaWiQ==[/tex]个，其中有[tex=2.143x2.429]ndZSw3zT0QTOVLVdoUto1Q==[/tex]个含子图[tex=1.786x1.286]J+vVZa2YaMpc6mJBbqVvWw==[/tex]，有[tex=2.143x2.429]lmhx48evnQMhi03NovPXig==[/tex]个含与[tex=1.214x1.214]kFXZ1uR8GjycbJx+Ts2kyQ==[/tex]同胚的子图。供选择的答案[tex=3.071x1.214]3KinXFh3SXhZ7nIe1y9KEV6aadxhhJWeEy6Dij1iObdMUZkY6ZA5J2dVVjPSuhEf[/tex]：(1) 1 ;(2) 2 ;(3) 3 ; (4) 4 ;(5) 5 ;(6) 6 ; (7) 7 ; (8) 8 。
1
set1 = {x for x in range(10)} print(set1) 以上代码的运行结果为？ A: {0, 1, 2, 3, 4, 5, 6, 7, 8, 9} B: {0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10} C: {1, 2, 3, 4, 5, 6, 7, 8, 9} D: {1, 2, 3, 4, 5, 6, 7, 8, 9,10}
2
水蒸气由初态[tex=6.5x1.286]oxZbMyOYj+RDjAeuo0jWXncfBtalGJrLeNVj4sLX64U=[/tex]定熵地流经渐缩喷管射人压力[tex=5.0x1.214]q6oTdPEyBrVfcD3aysxauw==[/tex]的空间。若喷管的出口截面积为[tex=2.714x1.214]nP9Gdlk6IFvJY1cavaw42g==[/tex],初速度可以忽略不计。试求喷管出口处蒸汽的压力、温度、流速以及质量流量。
3
空气进入喉部直径为 0.1 m 的缩放喷管，初速度可忽略，进口处的参数为 [tex=10.786x1.429]4gLGjTLHUTsN/EiaoCPKXjSCFQ9m3NzYoVK6LZPbUMpRGYiWW3bQCTXE4j8mwGh1sBAWwVQdEo5+9u1zxOVWWg==[/tex], 经等熵膨胀，出口温度为 [tex=4.429x1.286]fRK3v03V1MQaY/AqbLYNLSvFNWa107IynVn538zo5Fs=[/tex], 求喷管出口马赫数[tex=1.857x1.214]Z9rx7NZEg1fH5j6EhpFWJg==[/tex]
4
判断下列命题是否为真：（1）[tex=3.643x1.357]/5abqJjwKZ1qr+6hsVFF5EBvfq3ggOFNlHMClz0h9nk=[/tex]（2）[tex=2.929x1.357]rGJpyjIjJpbcoBTWxP0Jiw==[/tex]（3）[tex=4.5x1.357]2wycHMoqU83MyEp17iBils58bR7YLuCTI2G9NVAdlfY=[/tex]（4）[tex=5.214x1.357]CTz2gu+IIm1GgNmYMGaduCRtA41wnW4WqwRWwEhq6aA=[/tex]（5）[tex=4.857x1.357]1DcE2BMMOaZhTuxR/mjgsboXxfg5ET59Dp4I/jjEDuw=[/tex]（6）[tex=4.643x1.357]BSryrsQYOvTP2hTWRu6t4nAuJwlSs4L9jaq70EpB+Us=[/tex]（7）若[tex=6.0x1.357]y0IZLUnBO88nR8WBZYvd7QXv5S1OMINV5cQNzPyiyAc=[/tex]，则[tex=3.429x1.357]1brfPwTkVVIX4GfoMIUskA==[/tex]（8）若[tex=7.643x1.357]MhLfJXZnhbXiB0x3oNtFzThV4Y1mJxe1VYr7PkJE/T6hmTD3WWp+UxbNwvUQ6DHk[/tex]，则[tex=4.143x1.357]LZUA94ISo1po5HWsOVeBCjo0rMvj7uw3bGw5HiZenrI=[/tex]