發(fā)布時間：2018-05-10 21:44

  本文選題：結(jié)構(gòu)穩(wěn)健優(yōu)化設(shè)計 + 信息熵��； 參考：《電子科技大學(xué)》2015年碩士論文

【摘要】：結(jié)構(gòu)穩(wěn)健優(yōu)化設(shè)計的核心就是尋找最佳設(shè)計方案以確保約束條件和輸出性能在外部不確定性影響下均具有足夠的穩(wěn)健性,以輸出性能均值和標準差加權(quán)和作為目標函數(shù),在滿足約束條件情況下,尋求最佳優(yōu)化設(shè)計結(jié)果。該項先進技術(shù)在設(shè)計階段就考慮實際工程中廣泛存在的不確定性因素,并最大程度地降低這些因素對工程結(jié)構(gòu)性能的影響,從而提升結(jié)構(gòu)性能。因此在機械設(shè)計、航空航天、土木工程、振動控制和加工制造等諸多領(lǐng)域得到了極為廣泛的應(yīng)用。但是,傳統(tǒng)的結(jié)構(gòu)穩(wěn)健優(yōu)化設(shè)計依賴于設(shè)計者對權(quán)值的選擇,不同的權(quán)重可以導(dǎo)致截然不同的設(shè)計方案,限制了該技術(shù)的工程推廣應(yīng)用。針對這一問題,本論文提出不依賴于權(quán)重選擇的新穩(wěn)健優(yōu)化設(shè)計模型,并采用全新的高效求解方法以兼顧高計算精度和高求解速度,并最終實現(xiàn)所提方法在印刷電路板穩(wěn)健優(yōu)化設(shè)計中的應(yīng)用。具體研究內(nèi)容如下:(1)以標準差作為輸出性能穩(wěn)健性度量指標。本論文提出以性能均值和性能標準差乘積為目標函數(shù),以約束可靠度大于設(shè)計可靠度為約束條件的新型穩(wěn)健優(yōu)化設(shè)計模型。并引入稀疏網(wǎng)格法這種高效、高精度的方法來實現(xiàn)對該問題的快速求解。數(shù)值算例和工程算例驗證所提方法的可行性及高效性。(2)以信息熵作為輸出性能穩(wěn)健性度量指標。本論文提出以性能均值和性能熵乘積為目標函數(shù),以約束可靠度大于設(shè)計可靠度為約束條件的新型穩(wěn)健優(yōu)化設(shè)計模型。以核密度估計法確定輸出性能的信息熵,并結(jié)合線性擬合技術(shù)確定性能熵與設(shè)計變量之間的近似直接函數(shù)關(guān)系式,引入稀疏網(wǎng)格法實現(xiàn)對該問題的快速求解。工程算例驗證了所提方法的可行性及高效性。(3)以某印刷電路板的有限元分析模型為對象,以一階模態(tài)最大振幅的均值和標準差乘積為目標函數(shù)構(gòu)建穩(wěn)健優(yōu)化設(shè)計模型。對優(yōu)化前后印刷電路板模型分別進行了模態(tài)分析和隨機振動分析,有限元分析結(jié)果驗證了所提穩(wěn)健模型的有效性和可行性。
[Abstract]:The core of structural robust optimization design is to find the best design scheme to ensure that the constraint conditions and the output performance are robust enough under the influence of external uncertainty. The weighted sum of the mean and standard deviation of the output performance is taken as the objective function. In the case of satisfying the constraint conditions, the optimal design results are sought. In the design stage, the advanced technology takes into account the uncertainty factors widely existing in the actual engineering, and minimizes the influence of these factors on the structural performance of the engineering, thus improving the structural performance. Therefore, it has been widely used in many fields such as mechanical design, aerospace, civil engineering, vibration control and manufacturing. However, the traditional structural robust optimization design depends on the designer's choice of weights. Different weights can lead to different design schemes, which limits the engineering application of this technology. To solve this problem, a new robust optimal design model is proposed, which does not depend on weight selection, and a new and efficient solution method is adopted to give consideration to high calculation accuracy and high speed. Finally, the application of the proposed method in the robust optimization design of printed circuit board is realized. The main contents are as follows: (1) the standard deviation is used as a measure of output performance robustness. In this paper, a new robust optimal design model is proposed, in which the mean performance and the product of performance standard deviation are taken as objective functions and the constraint reliability is greater than the design reliability. The sparse mesh method is introduced to solve the problem quickly. Numerical examples and engineering examples verify the feasibility and efficiency of the proposed method. In this paper, a new robust optimal design model is proposed, in which the mean value of performance and the product of performance entropy are taken as objective functions, and the constraint condition is that the constraint reliability is greater than the design reliability. The information entropy of the output performance is determined by the kernel density estimation method and the approximate direct function relationship between the performance entropy and the design variables is determined by the linear fitting technique. The sparse mesh method is introduced to solve the problem quickly. The engineering example verifies the feasibility and high efficiency of the proposed method. The finite element analysis model of a printed circuit board is taken as an object, and the mean value and standard deviation product of the maximum amplitude of the first mode are taken as objective functions to construct a robust optimal design model. The modal analysis and random vibration analysis of printed circuit board model before and after optimization are carried out respectively. The results of finite element analysis verify the validity and feasibility of the proposed robust model.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TN41

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相關(guān)期刊論文 前1條

1 周慶忠;曾慧娥;;三次設(shè)計在機械零件設(shè)計中的應(yīng)用[J];機械工程師;1989年05期

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本文編號：1871024