超流氦浴中的热波传热研究

热波传热机制是超流氦传热非常重要的一个方面.在小热流密度的情况下,超流氦中的热波完全保持加热热流的波形,热量的传输完全靠热波来完成;随着热流密度的增加到一定程度,会在超流氦浴中激发量子涡旋.量子涡旋使热波发展成为热激波.在开放氦浴中,热波的波形不同于狭窄通道里的热波,在热波的尾部会出现一个冷却波;并且随着加热时间的变化,冷却波的形状和幅度会发生很大的变化.运用二流体模型和涡旋方程对超流氦中的热波进行了计算,实验结果与计算结果吻合得较好.关键词：超流氦热波量子涡旋热激波

Thermal wave heat transfer in the bath of superfluid he lium

Thermal wave heat transfer is one of the important aspects of the heat transfer mechanism in superfluid helium. The thermal wave keeps the shape of the input heat pulse when the heat flux is small, and energy is totally transported by the thermal wave. As the heat flux is increased to a certain value, the quantum vortices is initiated, which makes the thermal wave develop into the thermal shock wave. The shape of the thermal wave in an open bath is different from that in a narrow channel in that there is a cooling wave in the tail part of the thermal wave. The shape and the amplitude of the cooling wave vary significantly with the heat flux. The thermal wave is numerically calculated by the two-fluid mode and the vortex equation. The calculated results agree well with the experimental ones.