基于正癸烷在超临界压力下的热裂解反应机理,建立了考虑正癸烷裂解吸热反应及超临界传热现象的数值计算模型。采用该模型对正癸烷在3.45~11.38 MPa压力条件下的湍流传热过程进行了数值模拟计算研究,得到了详细的温度、速度、裂解转化率、物性及壁面热流密度的变化和分布情况。通过与已有的实验和数值计算结果的对比,对数值模型和计算软件进行了充分的验证。结果表明,本文的数值模型是准确、可靠的。这就为研究碳氢燃料的裂解吸热反应及超临界传热现象提供了一个有效的模拟计算工具。
A numerical model incorporating an n-decane thermal cracking mechanism at supercritical pressures is developed for studying n-decane supercritical heat transfer with endothermic pyrolysis. The model is employed for numerical investigations of the turbulent convective heat transfer of n-decane at supercritical pressures ranging from 3.45 MPa to 11.38 MPa. Detailed variations are obtained of the fluid temperature, velocity, pyrolytic conversion rate, thermophysical properties, and wall heat flux. The calculated results are compared and validated against the available experimental and computational data, showing excellent agreement. A computational tool is thus established for studying the supercritical heat transfer of hydrocarbon fuels with consideration of endothermic pyrolytic reactions.
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