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建立了微重力条件下火焰传播的三维非稳态计算模型。固体可燃物假定为可热解的纤维素薄片。气相模型包括考虑密度和压力变化的Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程，并且用六通量模型计算辐射传热。固相模型中连续性方程和能量方程的解为气相控制方程组提供相界面处的边界条件。数值方法中，分别对气相和固相方程组进行迭代耦合求解。用数值模拟的方法预估了不同微重力水平条件下重力加速度方向平行于可燃物表面方向时的竖板火蔓延过程，结果表明微重力水平对竖板表面的火焰传播过程有显著影响。
A three-dimensional unsteady calculation model of flame propagation under microgravity was established. Solid combustibles are assumed to be pyrolytic cellulose flakes. The gas phase model includes the Navier-Stokes equations that take into account changes in density and pressure, and uses a six-flux model to calculate radiative heat transfer. The solution of the continuity and energy equations in the solid phase model provides the boundary conditions at the phase interface for the vapor-phase control equations. In the numerical method, the gas-phase and solid-phase equations are iteratively coupled and solved respectively. Numerical simulations were performed to predict the course of vertical flame propagation when the direction of gravitational acceleration was parallel to the surface of combustibles at different microgravity levels. The results showed that the microgravity level had a significant effect on the propagation of flame on the surface of riser.