نویسندگان
دانشکده مهندسی عمران، دانشگاه صنعتی اصفهان، اصفهان
چکیده
در این نوشتار روش مودال طیفی به منظور مطالعه انتشار امواج عرضی در ورق‌های نازک مستطیلی با ضخامت ثابت و متغیر در راستای عرضی و با شرایط مرزی مختلف که تحت بارهای ضربهای قرار میگیرند، توسعه داده میشود. روش مودال طیفی که ترکیبی از روشهای سختی دینامیکی (DSM)، آنالیز طیفی و یا آنالیز فوریه (SAM) و روش نوار محدود کلاسیک (FSM) است، با مدلسازی دقیق توزیع جرم و سختی در حوزه فرکانسی منجر به پاسخهایی با دقت کافی میشود. این روش برخلاف سایر روشهای عددی از تعداد محدودی از اجزا برای نیل به پاسخ در حوزه زمانی بهره میگیرد که موجب کاهش زمان و هزینه لازم برای انجام محاسبات میشود. در ادامه پارامترهای حائز اهمیت در این روش معرفی و ضمن حل مثالهایی تأثیر هر یک از این پارامترها در دستیابی به پاسخ با دقت کافی مورد بررسی قرار میگیرد.
کلیدواژه‌ها
عنوان مقاله [English]
Modelling Wave Propagation in Thin Plates with the pectral Modal Method
نویسندگان [English]
- F. Shirmohammadi
- M. M. Saadatpour
چکیده [English]
In this article spectral modal method is developed for studying wave propagation in thin plates with constant or variable thickness. Theses plates are subjected to the impact forces and different boundary conditions. Spectral modal method can be considered as the combination of Dynamic Stiffness Method (DSM), Fourier Analysis Method (FAM) and Finite Stripe Method (FSM). Using modeling of continuous distribution of mass and an exact stiffness causes solutions in frequency domain. Unlike the most numerical methods, in this method refining meshes is no longer necessary in which the cost and computational time is decreased. In this paper the important parameters of the method and their effects on results are studied through different examples.
کلیدواژه‌ها [English]
- Rectangular thin plates
- wave propagation
- Spectral finite element method
- Spectral modal method
- Dynamic of Plates
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