東京大学航空研究所航空力学部構造関係研究室に設置された200kW急速幅射加熱構造物試験装置について,その機能と性能の大要を述べ,平面型対向加熱器を用いて行ったq(熱流入速度)分布および加熱能力に関する二三の測定結果を示した.本装置の設計仕様の要点は次の如くである.(1)熱源の熱発生量が大きく,熱慣性が小で急速な加熱が行え,高温が得られること.熱発生量は20Btu/ft^2 sec,通常の薄板あるいは薄殻構造加熱の場合の温度上昇率70℃/secおよび最高到達温度800℃以上を目標とする.(2)加熱制御容易なること.(3)試験体に接触せずに熱伝達が可能であること.(4)安全なること.(5)低廉なること.以上の諸点を検討の結果,相似型電子計算機の手法によって自動制御を行う赤外線ランプによる幅射加熱方式が採用された.試験の結果,本装置は最大出力時においてqcenter=20Btu/ft^2 sec,18/8鋼板(0.5t)を用いた場合の最大温度上昇率90℃/sec以上および最高到達温度約1,100℃が期待されるなど設計仕様を十分に満足し,各種構造物の加熱実験に極めて有用であると考えられる.

The outlines of the rapid radiant-heating equipment on a large scale of 200kW, which was installed recently in the Department of Structures, Aeronautical Research Institute, University of Tokyo, by the grant-in-aid for the scientific research of the Ministry of Education are described at first in this paper. The important requirements in the design of this epuipment were as follows: (1) rapid heat transfer rate not less than 20 Btu/ft^2 sec with large heat-generation and small thermal inertia, and maximum attained temperature not less than 800℃ and maximum rate of temperature rise not less than 70℃/sec for thin plate or shell structures, (2) easy controllability in heating, (3) non-medium heat transfer so as to make the measurements easy, (4) high safety, and (5) low cost. Taking into account the above requirements, the infrared radiant-heating method with the automatic control system of electronic analogue computer was adopted for this equipment. Next, some results of measurements on (1) the distribution of heat transfer rate resulting from the radiation and (2) heating capability of this equipment are described. That is to say, as expected in the design, the heat transfer rate, the maximum temperature and the maximum rate of temperature rise attained to 20 Btu/ft^2 sec, 1,100℃ and 90℃/sec, respectively, for 18/8 stainless steel plate blackened with Co_2O_3 paint (0.5mm in plate-thickness) under the maximum supplied power, 200kW, in the case where the distance between the furnace and the plate was 100mm. Accordingly, it was found that the equipment had enough performance and capacity for the use in the structural experiments at elevated temperature.

資料番号: SA4135043000