摘要
建立了耐热不锈钢试验喷管轴对称非稳态传热数值计算模型以及不锈钢在高水蒸气含量燃气中的氧化动力学模型,研究了氧化膜对喷管传热特性的影响。考虑了燃气对壁面的辐射换热及材料热物性参数随温度的变化,分别计算了结构材料无氧化膜、氧化膜表面光滑、氧化膜表面粗糙情况下的内喷管温度分布,通过理论计算值验证了数值计算模型的合理性与可靠性。结果表明,耐热不锈钢表面氧化膜的低导热系数使喷管热阻增大,但较大的氧化膜表面粗糙度强化了传热,2种因素综合作用决定了氧化膜对喷管传热特性的影响,氧化膜起到了隔热作用,计算结果可为表面热应力腐蚀数值模拟提供数据支持。
The transient axisymmetric heat-transfer computational model of heat-resisting stainless steel test nozzle and the oxidation model of stainless steel in the gas of high level water vapor are established, and the influences of surface oxide film on heat-transfer characteristics in nozzle are carried out. The temperature of unoxidized structural material and material with smooth surfaced and rough surfaced oxide film are calculated. Considering that the radiative heat transfer from gas to nozzle wall and variation of materials＇ thermal properties with temperature, the numerical result is verified by the theoretical value. The numerical results show that the low coefficient of thermal conductivity of oxide film augments the thermal resistance, but the great surface roughness enhances the heat transfer. The integrated influences of the two factors determine that the effect of oxide film is thermal insulation. The investigation provides the computational reference for the heat stress corrosion numerical simulation.
出处
《材料导报》
EI
CAS
CSCD
北大核心
2010年第24期1-4,共4页
Materials Reports
基金
国家自然科学基金重大研究项目(90916018)
关键词
试验喷管
耐热不锈钢
水蒸气
氧化膜
传热
test nozzle, heat-resisting stainless steel, water vapor, oxide film, heat transfer
