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Laminar flow control is next-generation technology which is expected to improve aerodynamic performance greatly. As for an application of laminar flow control in the aircraft design, it is important to consider comprehensive effects of laminar flow control system on design results. In this paper, we include the effects caused by additional laminar flow control system into the aircraft conceptual design tool and consider interactive effects on aerodynamic, propulsion and secondary power systems. Two types of laminar flow control technology have been considered and were applied to 200 passenger class transport aircraft. They are natural laminar flow (NLF) and hybrid laminar flow control (HLFC). Results indicated that NLF can improve lift / drag ratio and fuel consumption, and hence decreases the aircraft empty weight. Applying the HLFC improves lift / drag ratio and fuel consumption further. However, because of the additional weight of HLFC system, the maximum take-off weight of HLFC aircraft is equivalent to that of the NLF.

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Flow resistance and sediment transport for slip flow of sediment layer in a horizontal pipe are discussed experimentally, and following conclusions are obtained;Shear stress of bed surface of a sliding sediment layer can be estimated by the method of hydraulic radius dividion of the clear water flow section into two, for pipe wall and sediment wall. Conditions for occurrence of slip flow of sediment are explained by the relationship between energy gradient and thickness of sediment layer. The condition of incipient motion of slip flow can be estimated by equations of stable force balance.

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瞬時の管横断面上速度分布から壁面せん断応力τ^^-_wを求める前報の手法を応用して,単一管路における下流端の弁を瞬間閉鎖させた場合の乱流過渡流れの計算を行った.圧力,τ^^-_wなどの変化を調べ,管横断面上速度分布の変化も示した.乱流-層流計算,層流計算,擬定常計算,および著者らの一部が従来報告したτ^^-_wの表示式による計算を行い,圧力実測値と比較し検討した.さらに乱流過渡流れにおいて層流計算が適用できる条件を提示した.

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Cell tissue construction is one of the important issues for tissue engineering, which is a key-technology in regenerative medicine. Recently, several studies have reported, the in vitro fabrication of simple cell tissues. However, organs are made of some kinds of cells and they are complex tissues. Therefore, a technology to reproduce the complex structure and biological function of the organ is needed. In this paper, we propose an automated system for the construction of a cell tissue in vitro, based on hydrogel fiber. We designed a gel fiber discharge nozzle using laminar flow, and fabricated the lattice structure using laminar flow fiber. Through the experiments of the lattice shape structure construction, we observed the cell growth in the constructed lattice form, which proves the functionality of the structure.

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Research is widely conducted on air-diluted and EGR-diluted combustion of natural gas that contains no sulfur and less carbon. This study focused on a relationship between the laminar burning speed of methane-diluted mixtures and their heat release rate. In order to analyze the laminar burning speed with high accuracy, we measured the temperature of in-cylinder gas using an infrared absorption method. Using the data obtained, the pressure, temperature, and dilution ratio, we constructed a formula to predict the laminar burning speed with high accuracy. It has been experimentally shown that mixtures with nearly laminar burning speed of equivalence ratio and EGR ratio combination and the same ignition timing have the similar heat release rate.

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層流燃焼速度の計算のために改良を施した詳細反応機構を利用して，メタンからオクタンまでの飽和炭化水素の全異性体の化学構造と層流燃焼速度の関係を考察した．メタンとエタンを除き，主鎖の長さに層流燃焼速度は依存しないこと，分岐構造の複雑化に伴い層流燃焼速度が減少することを示した．また，反応経路解析と感度解析の結果から，ビニルラジカルとエチルラジカル濃度が層流燃焼速度と相関があることを明らかにした．これらのラジカルの反応や後続反応は，連鎖分岐反応となるからである．

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In this study, an optically accessed combustion vessel and high speed imaging were adopted to obtain laminar velocity measurements of spherically propagating hydrogen-air explosions at 0.06, 0.10, 0.175, 0.25 and 0.50MPa. Equivalence ratios of 0.4, 0.6, 0.8 and 1.0 were investigated and the influence of flame instability is discussed in terms of the Markstein number and flame instability burning velocity ratio (ratio of the laminar burning velocity at a flame radius of 60mm to the unstretched laminar burning velocity). The unstretched laminar burning velocity was approximately constant between 0.06 and 0.175MPa at any given equivalence ratio. However, the unstable laminar burning velocity and the flame instability burning velocity ratio increased with pressure. Markstein numbers decreased with increasing pressure. A liner relationship was observed, between Markstein number and flame instability burning velocity ratio.

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最近、主に壁境界流れに現れるとされた、局在した乱流構造が重要となる流れが、二次元の周期流体系においても見られることがわかった。本講演では、乱れ領域パターンが、流体領域のアスペクト比や外力の波数によって、どのように変化するか、数値的に検証した結果を報告する。

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