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arXiv · 0709.3515

Uma forma bidimensional que maximiza a resistência aerodinâmica newtoniana

Paulo D. F. Gouveia·Alexander Plakhov·Delfim F. M. Torres
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Abstract

(English) In a previous work [Nonlinearity, 20:2271-2287, 2007; arXiv:math/0703895] it is investigated, by means of computational simulations, shapes of nonconvex bodies that maximize resistance to its motion on a rarefied medium, considering that bodies are moving forward and at the same time slowly rotating. Here the previous results are improved: we obtain a two-dimensional geometric shape that confers to the body a resistance very close to the supremum value (R=1.4965<1.5). ----- Resumo (Portuguese) Um corpo bidimensional, apresentando um ligeiro movimento rotacional, desloca-se num meio rarefeito de partículas que colidem com ele de uma forma perfeitamente elástica. Em investigações que os dois primeiros autores realizaram anteriormente [Nonlinearity, 20:2271-2287, 2007; arXiv:math/0703895], procuraram-se formas de corpos que maximizassem a força de travagem do meio ao seu movimento. Dando continuidade a esse estudo, encetam-se agora novas investigações que culminam num resultado que representa um grande avanço qualitativo relativamente aos previamente alcançados. Esse resultado, que agora se apresenta, consiste numa forma bidimensional que confere ao corpo uma resistência muito próxima do seu limite teórico.

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Paulo D. F. Gouveia, Alexander Plakhov, Delfim F. M. Torres. 2007-09-21. Uma forma bidimensional que maximiza a resistência aerodinâmica newtoniana. https://arxiv.org/abs/0709.3515

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