考虑辐射传热的自适应化学理论数值计算

Radiation modeling associated with adaptive chemistry

通常实际湍流火焰中不同燃烧区域的化学反应特性大不相同,且辐射在热传递过程中扮演了非常重要的角色.采用辐射模型离散坐标DO法来完善自适应化学理论.基于详细化学反应机理,在不同区域使用不同的简化反应模型来进行化学项的求解.针对甲烷/空气预混火焰,对其燃烧行为进行了合理的重现,考虑辐射模型之后的计算结果与试验结果吻合得更好.

Most industrial flames are turbulent, exhibit different zones with totally diverse chemistry and have radiation as the dominant heat transfer process. The S4 quadrature version of the discrete ordinates radiation model was applied together with the Adaptive Chemistry （AdapChem） reduced kinetics modeling to a laboratory-scale, axisymmetric, co-flowing partially premixed methane/air laminar flame, previously predicted with success with AdapChem alone, to assess the effects of radiation on the distributions of other variables. Predicted results using the discrete ordinates method, that were compared herein with the experimental values reported in literature and with those predicted with AdapChem alone, showed that temperatures and species concentrations exhibit significant variations when radiation was considered. Nevertheless, the flame topology in terms of reaction structure remained essentially unchanged, although some differences were noticed. The predicted results approached more closely the experimental ones when radiation calculations were included.