應用有限元素法及邊界元素法於滾輪壓軋之熱應力分析

Thermal Stress Analysis of Roll by Finite Element Method and Boundary Element Method

蔡承穎(cheng-ying tsai)

指導教授 ： 黃健生

中原大學/工學院/機械工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100205

摘要

摘要

本文主旨在利用有限元素法(finite element method)及邊界元素法(boundary element method)做滾輪之熱應力分析，首先將實際三維滾壓鑄造系統因為對稱關係視為二維系統來分析。吾人利用邊界元素法將熔化的金屬池之邊界分割成二次方程式的邊界元素(quadratic boundary element)，並加以矩陣化後，再藉高斯(Gauss)積分法，求取溫度之近似數值解。至於滾輪之熱應力分析，則將邊界元素法算出熔化金屬與滾輪接觸面之溫度做為輸入溫度，以商用套裝軟體ANSYS做穩態分析，求得滾輪的應力分佈及應變分佈。在數值模擬解我們令熔化金屬的溫度分別為1600K,1700K及1800K，求得滾輪與熔化金屬接觸面的溫度，利用此求得溫度來分析在滾輪套筒及滾輪軸以不同材料組成時，其滾輪的應力分佈和應變分佈。吾人探討不同溫度之熔化金屬對滾輪熱應力的影響。

關鍵字

邊界元素法 ； 有限元素法

並列摘要

Abstract
This study investigates the effect of the thermal stress of the roll on the casting process by using finite element and boundary element methods. First we consider the 3D casting process as a 2D model due to symmetry. Then the boundary of molten metal pool is partitioned into quadratic boundary elements and use Gaussian integral method to forge the boundary element model. The equations of system are solved to obtain the temperature distribution of the contact interface between roll and molten metal.
To conduct the analysis on thermal stress of the roll, the commercial finite-element analysis package of ANSYS is used to compute roll stress and strain with various molten metal temperatures. The temperatures of molten metal are assumed to be 1600K, 1700K, and 1800K for numerical simulation respectively. The roll stress and strain distributions are computed with various material combinations of the roll sleeve and shaft. The maximum roll stresses of some cases are over the yield stress subject to higher molten metal temperature. This indicates that the roll is subject to plastic deformation.

並列關鍵字

boundary element method ； finite element method

參考文獻

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