In Section 3.2, the variation equation for Fourier media proposed by Biot is extended to the heat conduction of dual-phase-finite lag non-Fourier media, which leads to the variation equation with dual finite relaxation time.

• 第3.；4节讨论有限松弛-延迟型非Fourier介质的热力耦合问题的变分方程；将第3