摘要
采用有限单元-有限差分法研究了热流密度/对流换热边界条件下双向梯度板的瞬态热传导问题。采用细观力学方法结合混合律准则描述了材料的热物理属性,通过推导一种8节点高阶双向梯度单元建立了结构的连续梯度有限元模型。计算给出了在考虑组份属性的温度效应下,温度场的时间响应历程以及不同时刻温度场的空间分布形式,并与材料属性温度无关时的计算结果进行了比较,最后讨论了相关参数对瞬态温度场的影响规律。结果表明:温度较低时,组份属性的温度效应对瞬态温度场影响很小;在y方向热流密度载荷的作用下,温度场沿x、y方向均存在明显的梯度;x方向组份体积分布系数的增大,延长了温度场达到稳态需要的时间,绝对温度梯度沿x、y方向均增大,稳态温度场升高;增大y方向组份体积分布系数的值,情况相反。
Finite element-finite difference method is applied to the transient heat conduction analysis of two-directional graded plates under heat flux and convection boundaries.A continuous gradient model is established based on 8-node high-order two-directional graded elements with varying thermal properties described by the micromechanical method and rules of mixture.The response history and spatial distribution of temperature field at different times with temperature-dependent properties are calculated and compared to the counterparts with temperature-independent properties.Effects of several parameters on the transient temperature field are discussed finally.It can be concluded that the temperature-dependence of properties has few effects on the transient temperature field when the temperature is low.The temperature gradation obviously exits both along x and y directions under heat flux in y direction only.The duration time for transient heat transfer,absolute x-and y-temperature gradation and steady-state temperature field all raise as increasing the distribution coefficient of constitution volume fraction in x direction,while the reverse is true as increasing the distribution coefficient of constitution volume fraction in y direction.
出处
《应用力学学报》
CAS
CSCD
北大核心
2013年第4期563-568,648,共6页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金(10672075)
关键词
瞬态温度场
双向梯度复合材料
高阶梯度单元
有限单元-有限差分法
transient temperature field
two-directional graded composites
high-order graded element
finite element-finite difference method.
