円筒型黒体の黒さの精密数値計算
1956 年 40 巻 11 号 p. 495-498
詳細
1956 年 40 巻 11 号 p. 495-498
The author calculated the blackness of a cylindrical brack body with the base, varying specific length from 2 to 10, emissivity 0.25, 0.50 and 0.75, in the accuracy more than three figures.
The numerical calculation was done by the digital computor, “E. T. L. Mark II”, solving the simultaneous linear equations with maximum 27 unknown.
Besides, theoretical upper limit of the blackness of a black body was introduced, and it was compared with the blackness calculated by prof. Z. Yamauti using the specific coefficient of illumination of one term and three terms approximation. As a result, it is pointed out that his calculuted values exceed beyond this upper limit at some points, while author's values remain within it.(Fig. 1)
Moreover, it is suggested that the blackness of a spherical black body, which has a common opening with cylindrical black body, and contacts at the base of it, (Fig. 4) does not exceed that of cylindrical one, though this is nearly equal to that.(Fig. 3)
