具有质热源的方腔内对流传热传质及其非线性特性

以火灾为背景，对一个带有质热源的方腔进行了研究。针对不同Ra，浮升力比Nc，S_r和D_f，探讨了腔内流体的传热传质规律及其非线性特性。结果表明，存在临界R{a}_{\mathrm{c}}使流体流动由导热驱动流动转变为对流驱动流动，随着Ra增大质热源表面传热传质强度增加，流体由稳态流动转为振荡流动。当Nc>-1时，对流传热系数和对流传质系数增大，流体由稳态转化为倍周期振荡，最后转化为混沌。增大S_r和D_f可增强传热传质能力。

Study on heat and mass transfer and nonlinear characteristics with heat and mass source in cavity

In this paper, a square cavity with mass and heat source was studied with the background of fire. According to the different Rayleigh number(Ra) and buoyance ratio Nc, S_rand D_f, the heat and mass transfer law and nonlinear characteristics of the fluid in the cavity are discussed. The results show that the critical Ra_c causes the fluid flow to change from the heat-induced driving flow to the convection-driven flow. As Ra increases the heat and mass transfer of the surface of the heat and mass source, the fluid changes from steady-state flow to oscillating state. When Nc>-1, the convective heat transfer coefficient and the convective mass transfer coefficient increase, and the fluid transforms from steady state to double-period oscillation, and finally to chaos. Increasing S_r and D_f can increase flow and heat and mass transfer.