| Title |
Greitai konverguojančių skaitinių algoritmų sukūrimas trumpųjų bangų tyrimui / |
| Translation of Title |
Development of highly convergent numerical algorithms for short elastic wave simulation. |
| Authors |
Kriščiūnas, Andrius |
| Full Text |
|
| Pages |
90 |
| Keywords [eng] |
finite element method ; mode synthesis ; short wave simulation |
| Abstract [eng] |
The propagation of waves in elastic or acoustic media is mathematically formulated as linear partial differential equations of continuum mechanics, which can be numerically solved by discretization in space and time. Though mathematically and programmatically simple, numerical wave propagation models still have an inherent “weak spot”. They tend to distort the shapes of propagating waves when the space step of the computational grid is too big. Therefore, the most important problem arising in numerical simulations of short wave propagation is a very high demand for computing resources in case waves are short compared to the dimensions of the computational domain. A new algorithm based on the modal synthesis approach of optimally corrected modes has been developed in this work. This enabled to obtain the finite element models of significantly broader close-to-accurate modal frequency range compared to earlier models. Although the principal approach to the element synthesis was known before, its main drawback has been overcome in this work. The mass matrices of the new elements are diagonal and can be directly applied in numerical schemes of explicit dynamic analysis. |
| Dissertation Institution |
Kauno technologijos universitetas. |
| Type |
Doctoral thesis |
| Language |
Lithuanian |
| Publication date |
2017 |
