诱饵球镜面反射内壁的辐射传递系数计算

Radiative Heat Transfer Coefficient Calculation of Inflatable Sphere with Specular Inner Surface

针对内表面具备镜面反射特性的空间诱饵球,基于蒙特卡罗方法建立漫发射模型,推导光线的最大反射次数,利用光线在球腔的传播特性求解光线与球壁的多次反射交点,计算球面微元吸收的光束能量,获取不同反射率情况下单一球面微元对全部球面微元的辐射传递系数。计算结果表明,单一微元对球面各微元的辐射传递系数中存在2个峰值,分别为微元对其自身的辐射传递系数,以及微元对其球对称微元的辐射传递系数。随着反射率的增大,微元对其自身的辐射传递系数逐渐接近于微元对其球对称微元的辐射传递系数;当反射率接近于1时,两者的值近似相等。

Monte Carlo technique is used to calculate the radiative heat transfer coefficient for an in- flatable sphere with specular reflection inner surface. Light rays are emitted diffusely from a spherical fac- et and being traced. The maximum number of times a ray can be reflected is derived, and the multi-inter- sections of a ray with the inner side of spherical surface are obtained. Radiative heat transfer coefficients between a manually selected facet and the whole spherical facet are calculated at different reflectivities. The results indicate that there are two peaks in the calculated coefficients, the smaller one is the coeffi- cient between the selected facet and itself （ i. e. , the self-to-self coefficient） , and the larger one is be- tween the selected facet and its spherically symmetric facet （i. e. , the self-to-spherical-symmetry coeffi- cient）. The self-to-self radiative heat transfer coefficient gradually approaches and finally equals the self- to-spherical-symmetry coefficient as the reflectivity increases to 1.