Finite element analysis prediction of stresses in H. L. Hunley submarine by global-to-local model coordination.

摘要

H.L Hunley was a submarine of the Confederate States of America that participated in the American Civil War. On February 17, 1864, H.L.Hunley created history by becoming the first submarine to sink a enemy ship after its attack on USS Houstanic. After Hunley never returned to the shore and the details of its wreck were unknown. On August 8, 2000, H. L Hunley was brought to the surface after 136 years of its wreckage. The submarine is currently at the Warren Lasch Conservation Center located in Charleston.;This study focuses on the structural analysis of the H.L Hunley submarine to predict stresses and potential structural failure. Modeling the structure is challenging because of (1) the lack of symmetry due to its current position, (2) non-uniformity due to high corrosion, and (3) the riveted connections with more than 4000 rivets. Although connections between plates in ships are generally considered stronger and stiffer than the rest of the structure, this assumption is assumed to be invalid in the case of the Hunley because of the high and non-uniform corrosion. Since modeling the entire submarine and its 4000 rivet is impossible, the purpose of this study is to create a coordination procedure between the global model of the submarine with simplified connections and the local model of a riveted connection to affectively predict the stresses. The Global model is the whole submarine modeled using shell elements to decrease complexity. The local model consists of one of the riveted connections in the submarine. The validation of the procedure is discussed.