884aa四虎影成人精品,99久久国产综合精品女图图等你,97在线观看永久免费视频,久久精品国产精品亚洲38,ⅵdeodesetv性欧美

    郝際平
    （西安建筑科技大學(xué) 710055）

[提要]  用Ritz法研究了薄圓板的非線性振動(dòng)問(wèn)題，考慮了圓柱正交異性材料參數(shù)及邊界轉(zhuǎn)動(dòng)彈性約束剛度對(duì)非線性固有頻率的影響。為提高精度，在應(yīng)用Ritz法時(shí)，不同時(shí)設(shè)定反映本文研究問(wèn)題的泛函中所含有的兩個(gè)未知函數(shù)，而是建立兩未知函數(shù)之間精確關(guān)系的微分方程，在設(shè)定一個(gè)未知函數(shù)的基礎(chǔ)上，尋找最好的另一未知函數(shù)，然后再實(shí)施Ritz法。在設(shè)定一個(gè)未知函數(shù)時(shí)，用Legendre多項(xiàng)式構(gòu)造而成，即試圖通過(guò)這樣兩方面的努力來(lái)提高Ritz法的精度。結(jié)果表明；所述方法切實(shí)可行，以Legendre多項(xiàng)式構(gòu)成的域函數(shù)收斂快、精度高。
[關(guān)鍵詞]  薄圓板 非線性振動(dòng) Ritz法 Legendre多項(xiàng)式  固有頻率

Nonlinear vibration of circular thin plates has been investagted in this paper. The Ritz method was used with Legendre's multionmial expansion as a trial function of deflection that is one of the un-known funotion of energy funf:tional. Another unknown function-Airy stress function was obtained through differential relation between deflection and Airy stress function. Some examples are compared with the reference and they are in good agreement.
Keywords: thin slab; nonlinear vibration; Ritz method; Legendre's multionmial expansion