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为了深入理解火箭发动机再生冷却过程中碳氢燃料的流动传热规律,采用RNG k-ε湍流模型结合增强壁面处理方法对非对称受热(上壁面外侧加热)方形冷却通道内超临界压力甲烷的对流换热进行了数值研究。重点考察了加热壁面内侧的传热恶化以及由传热恶化和固壁热传导共同作用引起的热流异常传递现象,拟合得到了传热恶化的临界热流密度和起始内壁温关系式、加热侧内壁面和侧壁面内侧平均热流密度的预测关系式。结果表明:当外壁热流密度和质量流速比值高于0.288 k J/kg时,近壁流体流动加速诱发了加热侧内壁面的传热恶化;同时,固体区域温度畸变导致加热侧内壁面热流密度减小,热流更多地向侧壁面内侧传导。运行压力越低,该现象越显著。
In order to further understand the laws of flow and heat transfer of hydrocarbon fuel during rocket engine regeneration and cooling, RNG k-ε turbulence model combined with enhanced wall treatment was applied to the convection of supercritical methane in the asymmetrically heated (upper wall surface outside) Heat exchange conducted numerical studies. Focusing on the heat transfer inside the heating wall and the abnormal heat flux caused by the combined effect of heat transfer deterioration and solid wall heat conduction, the critical heat flux density and the initial inner wall temperature dependence of the heat transfer deterioration were fitted. Prediction of the average heat flux density inside the wall and side walls. The results show that when the heat flux density and mass flow rate ratio of outer wall are higher than 0.288 kJ / kg, the heat transfer near the inner wall of the heated side is accelerated due to the acceleration of the flow near the wall. At the same time, Small, heat flow to more conductive side wall. The lower the operating pressure, the more pronounced this phenomenon.