Zeitschrift für angewandte Mathematik und Physik ( IF 2 ) Pub Date : 2021-03-26 , DOI: 10.1007/s00033-021-01515-9 Hui Zhang
This paper is concerned with the long-time behavior of Moore-Gibson-Thompson equation with degenerate memory effect, given by
$$\begin{aligned} \tau u_{ttt}+\alpha (x)u_{tt}-b\Delta u_t-c^2\Delta u+\int \limits _0^tg(t-s)div\big (\beta (x)\nabla u(s)\big )ds=0, \quad ~in ~\Omega \times (0,\infty ), \end{aligned}$$where structural damping and molecular relaxation are both locally distributed, satisfying
$$\begin{aligned} \alpha (x)+\beta (x)\ge \delta ,\quad for~a.e. ~x\in \Omega . \end{aligned}$$Under general conditions on memory function g(t), namely, \(g'(t)\le -\xi (t)H(g(t)),\) and some basic restrictions imposed on \(\xi (t)\) and \(H(\cdot )\), we show that the solution energy decays to zero in a general rate. Moreover, through specific examples, our result allows to deal with a much larger class of g(t), including but are not limited to polynomial or exponential decay. This will improve some related results in the literature.
中文翻译:
具有局部和简并记忆效应的Moore-Gibson-Thompson方程的长时间行为
本文关注具有退化记忆效应的Moore-Gibson-Thompson方程的长时间行为,由下式给出:
$$ \ begin {aligned} \ tau u_ {ttt} + \ alpha(x)u_ {tt} -b \ Delta u_t-c ^ 2 \ Delta u + \ int \ limits _0 ^ tg(ts)div \ big(\ beta(x)\ nabla u(s)\ big)ds = 0,\ quad〜in〜\ Omega \ times(0,\ infty),\ end {aligned} $$结构阻尼和分子弛豫都局部分布
$$ \ begin {aligned} \ alpha(x)+ \ beta(x)\ ge \ delta,\ quad for〜ae〜x \ in \ Omega。\ end {aligned} $$在一般情况下,关于记忆函数g(t),即\(g'(t)\ le-\ xi(t)H(g(t)),\)和对\(\ xi(t )\)和\(H(\ cdot)\),我们证明了溶液能量以一般速率衰减到零。此外,通过特定的例子,我们的结果允许处理更大的g(t)类,包括但不限于多项式或指数衰减。这将改善文献中的一些相关结果。