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Due to the special structure, helical coil once-through steam generators (HCOTSGs) can withstand greater thermal expansion stress, have a larger heat exchange area, and cause the secondary flow phenomenon to improve the heat transfer capacity. Thus, it is inevitable to further study the thermal-hydraulic characteristics of the HCOTSG, a vital component of reactors. The optimal physical models were selected for different heat transfer areas by detailed investigation and comparison, to adopt in the TACS, a self-developed thermal-hydraulic analysis code that is accurate and widely-used in HCOTSG simulation. After verification with experiments of Santini, taking the IRIS reactor as the object, the TACS was employed to briefly study the thermal-hydraulic performances of the HCOTSG system at first, and then discuss the influences of thermal and geometric parameters on the HCOTSG. The analysis results showed that: the variation of the primary flow rate greatly affects the heat transfer coefficient of the primary side, while the maximum value of the heat transfer coefficient of the secondary side only changes drastically with the secondary flow rate; when the primary side flow drops to 70%, superheated steam is not generated on the secondary side; when the secondary mass flow rate decreases to a certain extent, the steam superheat degree increases by a small amplitude; the primary side inlet temperature has a little influence on the primary temperature difference, but significant influence on the two-phase zone length of the secondary side; the secondary inlet temperature has very little influence on the HCOTSG system; the inner diameter and the outer diameter of helical tubes have obvious influences, while the helical diameter has not.

航空宇宙技術研究所 7-9 Jun. 2000 東京 日本, National Aerospace Laboratory 7-9 Jun. 2000 Tokyo Japan, 回転する加熱曲管内を流れる流体は3つの体積力、つまり、遠心力、コリオリ力、浮力を受ける。加熱した回転曲管内の完全発達層流を相似議論と計算的研究を通して調べた。大きい浮力と小さい浮力に対しては、相似性の議論から巻きの緩い回転加熱管内の流体と熱輸送の特性は5つのパラメータ、即ち、ディーン数K(sub LC)、体積力比F、ロスビー数R(sub 0)、プラントル数P(sub r)、および浮力パラメータBまたは熱パラメータK(sub LB)に支配されることが明かになった。速度場と温度場の詳細な構造を、これらのパラメータの広い範囲について示した。複合パラメータK(sub LCR)を使って、摩擦係数とヌッセルト数に関する計算結果も広いパラメータ空間に対して示した。, The fluid flowing in rotating heated curved pipes is subjected to three body forces:centrifugal, Coriolis and buoyant forces. Fully developed laminar flow in heated rotating coiled pipes is investigated through similarity arguments and computational studies. Similarity arguments for small and large buoyancy clarify that the characteristics of flow and heat transfer in loosely coiled, rotating heated pipes are governed by five parameters: the Dean number K(sub LC), a body force ratio F, the Rossby number R(sub 0), the Prandtl number P(sub r) and a buoyancy parameter B or a thermal parameter K(sub LB). Detailed structures of velocity and temperature fields are shown for wide range of these parameters. By using a composite parameter K(sub LCR), computed results on the friction factor and the Nusselt number are also shown for a wide parameter space., 資料番号: AA0028635041, レポート番号: NAL SP-46