浪那点怒 浪那点怒
有朋自远方来,不亦乐乎??
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On a dark deser On a dark desert highway, cool wind in my hair Warm smell of colitas rising up through the air Up ahead in the distance, I saw a shimmering light My head grew heavy, and my sight grew dimmer I had to stop for the night There she stood in the doorway; I heard the mission bell And I was thinking to myself, 'This could be Heaven or this could be Hell' Then she lit up a candle and she showed me the way There were voices down the corridor, I thought I heard them say... Welcome to the Hotel California Such a lovely place (such a lovely place) Plenty of room at the Hotel California Any time of year, you can find it here Her mind is Tiffany-twisted, She got the Mercedes Benz She's got a lot of pretty, pretty boys, that she calls friends How they dance in the courtyard, sweet summer sweat. Some dance to remember, some dance to forget So I called up the Captain, 'Please bring me my wine' He said, 'We haven't had that spirit here since 1969' And still those voices are calling from far away Wake you up in the middle of the night Just to hear them say... Welcome to the Hotel California Such a lovely Place (such a lovely face) They livin' it up at the Hotel California What a nice surprise, bring your alibis Mirrors on the ceiling, the pink champagne on ice And she said 'We are all just prisoners here, of our own device' And in the master's chambers, they gathered for the feast They stab it with their steely knives, but they just can't kill the beast Last thing I remember, I was running for the door I had to find the passage back to the place I was before 'Relax' said the nightman, We are programed to receive. You can check out any time you like, but you can never leave
空气动力学效率 当F1车队告诉你他们的空气动力学效率提高了多… 空气动力学效率 当F1车队告诉你他们的空气动力学效率提高了多少个百分点的时候,很多人以为是赛车的下压力增大了或者风阻减少了。这是F1车迷很容易犯的错误。 必须指出的一点是,F1赛车的下压力和风阻系数是正相关的。它的意思就是想要获得更大的下压力,你的赛车必须承受更大的风阻系数。F1车队空气动力学专家所说的空气动力学效率显然就不会是这两个要素单方面的变化。   空气动力学效率=下压力系数/风阻阻力系数 如上图所示,这是一块简化的尾翼截面。空气动力学的基础知识告诉我们,由于尾翼的下缘长度比长缘长,下部空气流动速度高于上部,导致下部空气压强小于上部,于是尾翼产生了下压力。 下压力虽然产生了,但是红色线条所代表的扰流也因此而产生。由于下部气流不得不过早地与尾翼下缘分离,在尾翼下后方会产生非常大的空气滞留区域,空气在这个区域不规则地运动,严重地阻碍了尾翼的前进。 尾翼弦线与水平线之间的夹角称为尾翼的攻击角。随着这个角度的增大,尾翼的下压力会越来越大,尾翼的风阻也会随之增大。在观察GT赛车的时候,你会发现尾翼组件的立板上有滑槽,这就是帮助赛车调整下压力的。 每一块尾翼都有其最佳攻击角,在这个角度下,下压力系数与风阻系数之比示最大的。F1空气动力学专家都会将尾翼布置于这个角度小。 设计尾翼,并不是下压力越大越好,而是空气动力学效率越大越好。
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