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福山内港地域は瀬戸内海につながる福山港入江の周辺地域であり，海洋由来の自然災害による危険性を有している．南海トラフ地震発生時の福山港沖合では，津波によって通常潮位より最大1.4mの海面上昇が生じると予測されている．この津波が福山港入江に侵入した際の海面変動を数値計算で求めたところ，津波は最大2.8mまで増幅することが示された．津波の到達が満潮時と重なった場合，平均海水面からの高さが最大4.6mの海面上昇となる．さらに，副振動や吸い上げ効果，吹き寄せ効果によって，最大1m程度の海面上昇が加わることも予想される．福山内港地域の護岸堤防の一部は標高3.5m程度であり，地震動による堤防の破損がない場合であっても平野内部に津波が侵入する危険性があると言える．, The Fukuyama inner harbor area is located around the Fukuyama Port Inlet that connects to the Seto Inland Sea.This area has some risk of natural disasters from the ocean. The Nankai Trough Earthquake is predicted to cause a sea level rise of 1.4 meter in the offshore area of Fukuyama Port due to tsunami. We calculated the tsunami propagation in the inlet and showed that the tsunami would be amplified up to 2.8m in maximum height. If the tsunami would approach in full tide, the sea level could rise by about 4.6 meter. In addition to that, the secondary undulation, the inverse barometer and wind-drift effects could cause an additional rise of sea level by 1 meter. Nevertheless, a part of the embankment around the inlet is about 3.5 m high. Therefore, there is a risk of tsunami intrusion into the Fukuyama plain, even if the embankment would not be damaged by severe seismic motions.

細胞は内的あるいは外的要因によって, 前後方向の極性を形成し, 方向性をもった移動を可能にしている. 細胞群の運動は, 生物種や組織を超えて共通する部分がある. 例えば, 細胞性粘菌, MDCK細胞では, 直進運動などの単純な運動だけでなく, 回転などの運動も存在する. この回転運動は様々な器官や組織で観察されるが, ここから細胞細胞群の移動と形態形成の過程の間には, 生物種を超えた何らかの普遍性があるのではないかと推測できる. 本論文では, 細胞群の様々な運動モードがどのように三次元および二次元の形態形成のプロセスに効いているかを見出すために, 幾つかの生物種の特徴的な運動モードを例として示した後, 数理モデルを用いてこれらの運動モードが再現できることを示す. さらに再現された運動モードはある種の堅牢性(robustness)を持つことを示す.

A numerical method was developed to solve the three-dimensional potentialdistribution about a point source of direct current located in or on a cylindrical shapedarbitrary conductivity distribution. In order to express the cylindrical -shaped outerboundary, we used cylindrical coordinate system in formulation and applied Neumannboundary condition to all external boundaries. For performance evaluation, numericalresults obtained by this method were compared with experimental results usingsimulation sample (conductive plastic). These results had roughly agreement. Theseagreements support the validity of new method.

When a tornado travels very fast, an unsteady pressure differential between the inside and outside of a building is generated by suddenly-dropped atmospheric pressure due to the tornado. However, there is little information about the characteristics of a force caused by the pressure differential. The authors developed an experimental system which generated a suddenly-dropping pressure around a building model in a calm condition using a gusty wind tunnel. The effects of an opening area of a building wall on the force generated by the pressure differential were studied using the system. We also performed some numerical simulations and compared with the experimental results. It was found that the bigger force of pressure differential was generated in a case of the smaller opening area.

The transition of tornado-like vortices is numerically investigated with the use of nonhydrostatic axisymmetric and three-dimensional models. Tornado-like vortices are generated by imposing a specified external force near the center axis of the computational domains that are rotating at a constant angular velocity. When the vortex transition from one to two-celled vortex occurs, there is an overshoot of the radial inflow near the surface. The overshoot flow turns upward, rebounding outward to a larger radius. At the same time, downdraft penetrates to the surface at the rotating axis. The overshoot is generated by coupled effects of inward advection and inward pressure gradient force. The downdraft is caused by downward pressure gradient. Thereafter, the two celled vortex transform to a multiple-vortex structure because the horizontal shear and Kelvin-Helmholtz instabilities occur in the non-axisymmetric flow.

In order to evaluate the impact of missiles caused by tornado, a study on the velocity prediction of flying debris in a tornado-like vortex was carried out by numerical simulation. A series of unsteady flow fields of a tornado-like vortex was generated by Large Eddy Simulation. The aerodynamics of debris was examined and the range of aerodynamic parameters of debris resulting building damage was investigated. The trajectories of flying debris and the statistical distributions of the maximum speed of debris were obtained in various conditions i.e. the release height and the aerodynamic parameter of debris, the maximum tangential wind speed, the radius of maximum tangential wind speed and the traveling speed of tornado. Relation between the maximum ground speed of debris and the maximum wind and traveling speed of tornado was obtained as a function of aerodynamic parameter of debris.

This note was summarized when optimizing numerical calculations. Under the personal environment supposing PC which recent years formed into the multi-core, the important points about fundamentals of vectorization, parallelization, memory access, etc. were arranged for the double loop of simple matrix calculation for the example.

SU(2) × U(1) 対称性に基づくゲージ場理論から導出されるクォークセクターに対するディラック型の質量行列の解析を行う．質量行列の形はパウリ行列の中心拡大により生成される水平対称性のゲージ場理論から導出される質量行列と同等の形となるが，湯川結合定数に関して簡潔な表記となっている．観測結果を再現するためには，一つの位相の値とこれら湯川結合定数の間に大きな階層性があることが必要となる．

This study investigated bathymetry changes and its causes in the access channel and basin of Kanazawa Port, which is suffering sedimentation, by analyzing field data of wave, current, sediment size and bathymetry. The results showed that the amount of the sedimentation is 168,000 m3/yr and that sands and silts transported by south-westward currents during storms and long-period oscillations inside the port cause the sedimentation. The numerical simulation model incorporating those sediment movements has well predicted the bathymetry change in the channel and basin.

二つの部分系からなる系の間に,熱平衡が成り立つかどうかを数値計算によって調べた。一例目はA,B粒子からなる混合気体で,二種類の気体が部分系となっている場合である。部分系の一つが壁と熱的に相互作用をするが,他方は力学的に相互作用する場合である。二例目は,気体系と非線形格子系が部分系をなしている場合で,気体系のみが壁と熱的な相互作用をする場合である。二例とも,数値計算によって部分系間に熱平衡が成り立つことが数値的に示された。気体-気体系では,着目する粒子の運動がブラウン運動的であることも示される。, The possibility of attainment of the thermal equilibrium between two subsystems is numerically studied, where one system thermally contacts with the walls of vessel and the other, not thermally but mechanically, by numerical method. It is also shown that the thermal equilibrium between gas system that contacts thermally with the wall and a nonlinear lattice system can be attained.

Possibilities of the future society with hydrogen utilization have been discussed as one of the advanced technologies for the improvement of the energy and environmental problems in recent decades. In order to go on generating the effective energies by oxidizing the hydrogen with a fuel cell etc., it is necessary to establish the total system for producing, transporting, storing and transferring the hydrogen safely and stably. At that time, it can also be essential to use the hydrogen as a liquefied gas as well as a compressed gas. In this study, the operation of a superconducting level sensor for liquid hydrogen with a magnesium-diboride wire is numerically simulated on the basis of experimental results carried out previously. The time evolution of temperature distribution along the wire is calculated with a heat balance equation including the cooling effects of liquid hydrogen and its vaporized gas. The influences of the wire size and material properties on minimum propagating current and power consumption in the gaseous hydrogen are evaluated toward the optimal design of the level sensor.

上部に吸い出し口をもつ円筒形の対流域と，下部に正方形水平断面の直方体収束域をもつ竜巻発生装置を模擬した解析領域を設定し，ラージ・エディ・シミュレーション(ＬＥＳ)を用いた数値計算によって竜巻状の渦を生成した。流入気流条件，解析領域の大きさや形状等が渦の発生条件や渦内の気流性状に及ぼす影響を明らかにした。さらに，渦内の低圧部の分裂も見られるなど，種々の竜巻状の渦を再現し，今回用いた計算手法が，実際の竜巻内の気流性状を検討するツールとしての可能性を示した。, A tornado-like vortex was generated numerically by Large Eddy Simulation. The calculation region was designed to reproduce the wind flow in a tornado simulator. The tornado simulator consists of a convection region and a convergence region. An unsteady flow field of vortex was generated and examined the flow characteristics with varying the inflow conditions and the configuration of calculating region.

Behavior of the fine sediment around vegetation is still unknown because knowledge of complex flow around vegetation is limited. Moreover, only limited research has been done on flow resistance and fine sediment transport inof open channel flow wherewith vegetation that considers a growth type, which includinge emergent plants, submerged plants, and land plants, etc., has been considered are hardly researched. This study considered the growth type of vegetation and analyzed the flow of water with vegetation that considers a growth type of vegetation by using laboratory experiments that includeds various methods such as LDV and numerical simulations employing turbulence model. For emergent plants, it was found that the lateral momentum of transport reachedtakes a peak value at a certain vegetation density which wasis much larger than the density of the actual reed field, and the cause of this wascause related greatly to the shape of the horizontal vortex. WhenFor the case in which the ratio of a vegetation group's length to width wasis nearly 1:.7, the horizontal eddies were generated at the boundary of the vegetation group's region, and the momentum of transport reachedtakes a peak value. A numerical computation employing SDS&2DH turbulence models was introduced to investigate the resistance and the roles of the surface and submerged vegetation layers, and the effect of generated turbulence. Theseis models allowed us tocan predict the mean velocity of the surface and submerged vegetation layers, and provided information on the shapes of vortices, lateral distributions of the depth averaged flow velocity, and turbulence statistics. A phenomenon involving wavy motion of very flexible submerged vegetation (termed honami) was observed, and the displacement of the plants was found to be closely associated with the structure of the turbulent flow, which yieldeds a larger Reynolds stress near the top of the vegetation layer. Finally these experiments and simulations applyied to the development of methods for catching fine sediment method for the wetland conservation.

application/pdf, 学位論文, お茶の水女子大学人間文化創成科学研究科博士(理学)学位論文･平成27年3月23日授与(甲第162号)

Light illumination effects on semiconductor device characteristics are investigated by numerical simulation. Numerical solutions for Poisson equation, current equations and continuity equations are obtained using the finite difference method. Depth profiles of potentials, current densities and carrier concentrations are evaluated for Si pn junctions under illumination. Physical mechanisms in semiconductors can be understood referring to calculated results.

In this paper, the understanding of an algorithm for numerical computation via Newton's method is investigated. In order to demonstrate the efficiency of Newton's method, an example of how to use them is given. After introducing the mathematical tool related to matrix algebra, the new iterative technique that is based on Newton's method for solving a set of the algebraic Riccati equation is applied. It is shown that the proposed algorithm guarantees the local quadratic convergence. A numerical example to show the validity of the Newton's method is given for the practical control problem.

円周率πを表すいわゆるブランカーの公式の初等的な導き方を示し,その打切り誤差が,π/4の逆数をグレゴリー級数で表したときの打切り誤差と正確に一致することを示した。またその導き方を応用して,自然対数の底eの収束の速い連分数展開を与えた。さいごにそれらの無限連分数の数値計算法を検討して,これまでに知られている直接的な計算法をブランカーの公式に当てはめるとすぐ桁あふれが起こってしまう(最初の10項しか計算できない)こと,また本論文で提案される計算法によれば,桁あふれを大幅に抑えられる(4百万項計算できる)ことを示した。, In this paper, we have shown an elementary method to derive Brounker's Formula, an expansion of the number π into continued fraction, and proved that its truncation error is identical with that of the evaluation of the reciprocal of π/4 by Gregory's series. By the same method, we obtained an infinite continued fraction which converges very rapidly to the value of e, the base of natural logarithm. We finally examined numerical evaluation of infinite continued fractions, and have shown that Brounker's Formula is practically intractable by the ordinary straight-forward method, because overflow occurs in the very early stage of computation, while its evaluation can be continued much further without overflow by the method presented in this paper.

In numerical calculation using computers, it is not possible to avoid the influence of rounding errors. Therefore solutions obtained by numerical calculation include some errors. To evaluate the error, the computation with guaranteed accuracy has been proposed. The purpose of this paper is to explain the method easily. At first, we explain a system of the floating-point number based on IEEE standard 754 in detail. Then, we introduce a library for interval calculations of complex numbers using a new standard of C language, that is, C99. Finally, we verify the effect of the numerical calculation with guaranteed accuracy by solving an algebraic equation.

The feature of the basic theorems that are related to the numerical computation and some examples of how to use them are introduced through the simulation. The new iterative techniques for solving the algebraic Riccati equation and algebraic Lyapunov equation are used for weakly-coupled systems as an application. It is shown that the free numerical application tool which is called Octave is very powerful tool and it is available for the understanding of the numerical computation for undergraduate students in the early learning stage.

大規模な山岳が回転成層場に置かれている際の，非定常流および定常流による渦の生成を考えた。非定常流において計算初期に生成した，地表から山岳頂上に及ぶ低気圧性渦の渦度は，流れが山岳斜面を下る際のストレッチ効果により生成されること，無次元渦度はフルード(Fr) 数を用いてFr?1/2 に比例するという傾向がみられた。この傾向は先行研究の線型理論を発展させることで説明することができた。定常流下の状況では，山岳風下側に次々と生成される正負の鉛直渦度を持つ渦対が再現できた。この渦対について計算したストローハル(St) 数はSt ? 0.15 という一定の値を得た。この渦対の形成は，Fr 数が小さい場合でかつロスビー(Ro) 数が十分大きい場合に限ることが判明した。傾圧不安定の理論を適用した結果，渦形成は傾圧安定の条件でおこることが判明した。, Generation of cyclonic vortices in the middle layer of flow around a large mountain like Tibet andRocky was investigated by means of a 3-D nonhydrostatic meteorological prognostic model. Specialattention was paid on the effects of earth rotation and stratification on the vortices detached successivelyfrom the slope of a high and large horizontal scale mountain. It was found the successive formation anddetachment of such 'von Karman-like vortices' occurred in the flow regime at high Rossby numbers Roand low Froude numbers Fr. It was successfully divided by the criterion of baroclinic instability. Thismeans that if the condition is unstable baroclinically, a lee vortex is destabilized into three dimensionalone, while under baroclinically stable conditions the lee vortex with vertical axis retains its standingstructure and remains for a long time in the middle layer.

ヨーロッパにおけるエアロゾル重量測定値に含まれる水分量を数値モデルにより計算した。エアロゾル重量は通常定められた標準の低湿度環境下で一定時間保存された後に測定される。その結果, エアロゾル内の水分はほぼ蒸発すると考えられている。しかし本研究では, 保存後も無視できない量で水分が残存する事を確認し, さらなる保存時間の必要性を示した。, The contribution of liquid water to measured aerosol mass was assessed using a numerical approachfor European measurement data. Aerosol mass is usually determined after conditioning of the filterunder dry condition for a predefined period according to a standard procedure. Consequently, water inaerosols is assumed to be at very low concentrations. However, we find indications that the equilibriumof aerosol is not fully established and water is not completely evaporated after the conditioning.

わが国における高潮対策事業では，防潮堤の設計に用いる高潮や高波の条件として，伊勢湾台風を標準台風として推算された値が一般に用いられている．伊勢湾台風は，昭和34年に名古屋地方を襲って，わが国において未曾有の高潮災害を起こした台風である．伊勢湾台風が既往の最大級の台風であるところからこれが東京湾や大阪湾等における高潮対策事業に用いられているが，この台風の再現期間については必ずしも明確に調べられていない．近年，防災事業であっても事業の投資効果が問われるようになってきている．そこで，本論文は，投資効果を考慮して，防潮堤の最適設計を行う手法を提案したものである．投資効果の判定としては，防潮堤の建設費と維持管理費に加え，防潮堤の耐用年数間における期待被害額の総和を最小にする最適条件である．そして，この最適条件における再現期間の台風で設計すればよいことになる．例として，この方法を大阪港の防潮堤に適用して結果について報告する．, In Japan Isewan Typhoon which caused the severest damages in the recent history of Japan has been employed as a standard typhoon to make a master plan for storm surge protection project and a design for storm surge barriers. The employment has been done without consideration of the return period of the Typhoon. The efficiency of the investment has recently been taken into account even for disaster protection structures. The present paper proposes how to determine design conditions for storm surge barriers from the view point of an economical design because numerous data for storm surges can now be obtained and also numerical simulation tool for storm surges can be utilized. The design condition of the storm surge barriers along Osaka Bay is optimized for an example in the present paper.

The procedure to estimate the hydraulic conductivity of the sand sediment that is characterized by an inclusion of large gravel particles and cobbles in it was proposed. Assuming the descriptive cylindrical soil model representing sand, gravel/cobbles and void structures and applying the continuity law of water movement to the soil model, the functional relationship between the hydraulic conductivity of the sand sediment soil to be evaluated, the hydraulic conductivity of the sand soil measured by the laboratory or field permeability test, and the mass content of the gravel and cobbles in the soil was derived. The accuracy of the functional relationship mentioned above was examined by the series of the one-dimensional permeability test. A good comparison between the measurements and the estimation by the functional relationship was obtained. A numerical example was given to show the practical influence of the mass content of the gravel/cobbles on the prediction of the storm runoff in the sand sediment soil., 礫と巨石が混入する土砂堆積地盤の透水係数の推定方法を提案した。まず、土砂堆積地盤を構成する砂、礫・巨石および間隙を模式的に表した円筒状の土要素モデルを想定し、流れの連続条件を適用した。これにより、土砂堆積地盤全体の透水係数、室内あるいは現場透水試験で測定される砂の透水係数、ならびに土中に占める礫・巨石の質量含有率の関係を記述する理論式を誘導した。次に、この理論式の精度を、室内一次元透水試験により調べた。試験結果と理論式から推定した値の間に良好な一致が得られた。最後に、土砂堆積地盤における豪雨流出問題を対象に、流出量の推定結果に与える礫・巨石含有率の影響を示した。

In this paper, the numerical calculations of laser propulsion for space vehicle are discussed. For calculating the behavior of ablation, it is necessary to do with the solid, the liquid and the gas at the same time. This process was calculated with the hydrocode based on a highly-accurate scheme CIP-CUP (Cubic-Interpolated Pseudoparticle Combined Unified Procedure) method. With this scheme, the efficiency by C(sub m) (the momentum coupling coefficient) is evaluated for the cases of single pulse and some target shapes. In order to confirm the result, experiments were performed with a pendulum and a semi-conductor load-cell., 資料番号: AA0032819042, レポート番号: NAL SP-53

資源・素材学会平成28年度春季大会、2016年3月28日（月）～30日（水）、東京大学本郷キャンパス、東京, 不安定岩体が落下するメカニズムを明らかにすることを目的として行われている長期計測により、気温変化によ り不安定岩体に熱変形が生じていることが明らかになった。熱変形に関する数値計算では、傾斜変化はある寸法 の不安定岩体でピークを示すことが明らかになった。傾斜変化がピークとなったときの不安定岩体の亀裂長さをLcと定義し、岩盤の熱伝導率・比熱・密度・ポアソン比・不安定岩体形状からLcを推定する式を作成した。岩盤の物性値から推定したLc・落石の寸法と頻度・節理間隔の間の関係についても検討した。

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, 計算流体力学(CFD)の方法は、昨今では科学技術分野の諸問題の解法に広く適用されている。その内でも差分近似は有用視されている。このために、差分近似理論や応用、および多くの差分スキームが開発され、計算の精度向上と信頼性向上が図られている。しかし、差分法によって求められた数値結果の特性と信頼性についての問題点も残されており、差分近似がエントロピー解(すなわち物理的に妥当な一意解)に収束した場合でも例外ではない。この種の問題は実質的に数値的であり、実際の計算は固定した有限値の差分増分に対して行われ、ゼロの増分に対してではないことが認識されるときのみに解析可能であった。ここでは、このような数値挙動の問題を取り扱い、オレニクE条件を用いた解析結果を示した。さらに、将来これらの問題点についても、その取り組みを提案した。, Nowadays the method of Computational Fluid Dynamics (CFD) is widely used for solving various problems in science and engineering fields. Difference approximation is a popular method for the CFD. Many works have been done for the theory and application of the difference approximation, and various difference schemes have been developed to improve the quality and reliability of computations. But there still remain a few problems in the quality or reliability of numerical results obtained by the difference methods. Some of the problems happen even if the difference approximation might converge to the entropy solution (i.e., the physically relevant unique solution). Such problems are really numerical, and can be analyzed only when it is recognized that a practical computation is conducted with the difference increments fixed finite values, but not with those tending to zero. Here it is concerned with such problems of numerical behaviors. Some results obtained from the analysis related with the Oleinik's E-condition are shown. Then some future problems are proposed., 資料番号: AA0028635057, レポート番号: NAL SP-46

微小重力下の凸状固液界面で半導体結晶を成長させる条件を調べるため、数値計算を行った。計算コードは境界適合座標系(BFC)法に基づいている。現在のコードは、エネルギー輸送方程式、渦度輸送方程式、流れ関数方程式、エネルギーバランス方程式のような、非定常的支配方程式を同時に解けるよう改良された。このコードを使って、色々な重力レベルで界面の位置と界面の形状変化の両方を追跡した。計算の信頼性を調べるため、地上実験を行った。これらの結果の比較から、数値的に得られた初期界面形状は、実験的に得られたものと良く一致することが明らかになった。界面形状変化の傾向を探るため、形状を放物関数でフィットし、2次項の比例係数を求めた。実験結果の傾向は数値計算で得られたものの約2倍の急勾配であった。しかし、計算した温度プロファイルは実験的に測定した温度と良く一致した。, In order to investigate conditions to grow semiconductor crystals with convex solid-liquid interface under microgravity, numerical calculations have been carried out. The caculation code is based on the Boundary Fitted Coordinate (BFC) method. The current code has been improved so as to simultaneously solve nonsteady governing equations, such as an energy transport equation, a vorticity transport equation, a stream function equation, and an energy balance equation. By using this code, both interface location and interface shape change are traced for various gravity levels. In order to investigate reliability of the calculation, a ground-based experiment is carried out. From the comparison of these results, it is clarified that the numerically obtained initial interface shape well agrees with the experimentally obtained one. In order to obtain the trend of the shape change, the shape is fitted by a parabolic function and a proportional coefficient of the second order term is obtained. The trend of the experimental result is about twice as steep as that obtained by calculation. However, calculated temperature profiles well agree with experimentally measured temperatures., 資料番号: AA0029300008, レポート番号: NASDA-TMR-000007E

微小重力下で凸型形状の固液界面を有する半導体結晶が成長する条件を検討するために、数値計算を行った。本研究では、境界適合座標(BFC)法を用いた。支配方程式として、円柱座標系における熱伝導方程式を使用した。安定性を良くするために若干の変換技法を用いた。数値計算の信頼性を評価するために、計算結果を実験結果と比較した。, In order to investigate conditions to grow semiconductor crystals with a convex solid-liquid interface under microgravity, numerical calculation is carried out. In this study, the Boundary Fitted Coordinate (BFC) method is used. The thermal conduction equation in the cylindrical coordinates is used as the governing equation. To get the better numerical stability, several transformation techniques are considered. To evaluate the reliability of numerical results, the calculation results are compared with the experimental results., 資料番号: AA0002208009, レポート番号: NASDA-TMR-990006E

航空宇宙技術研究所 24-26 Jun. 1998 東京 日本, National Aerospace Laboratory 24-26 Jun. 1998 Tokyo Japan, 垂直板に入射する高温ジェットは地上からロケットを打ち上げる際に極めて重大な問題になることがある。これまで多くの研究が行われてきた。しかし、流れの機構は充分には明らかにされていない。本研究では垂直板に入射する超音波ジェットについて相互に作用する流れの場の数値計算を行う。ノズル出口と垂直板間の変位を変え、そして相互に作用する流れの場に及ぼす変位の影響を数値的に調査する。計算された流れのパターンと圧力分布は実験との良い一致を示した。, High temperature jet impinging on the wall sometimes become quite serious problems in launching the rocket from the ground. Several researches have been conducted by some authors. However, the flow mechanism has not been revealed sufficiently. The interacting flow fields of supersonic jet impinging on the wall are numerically simulated. The displacement between the nozzle exit and the wall is varied and the effects of the displacement on the interacting flow field are investigated numerically. The calculated flow patterns and pressure distributions show good agreements with experiments., 資料番号: AA0001958057, レポート番号: NAL SP-41

Using the numerical simulation of the turbulent boundary layer over rough surfaces with a refined k- e turbulence model presented previous paper, a series of calculations were done on the characterized model cities. The change of the mean wind speed and the turbulence intensity due to the configuration of surface roughness was investigated. The variation of the thickness of the boundary layer, the profile of the mean wind speed and the intensity of turbulence against the density of surface roughness, i.e. buildings and houses, was obtained for the wind resistant design.

航空宇宙技術研究所 12-13 Jun. 1997 東京 日本, National Aerospace Laboratory 12-13 Jun. 1997 Tokyo Japan, 曲管内と直交回転直管内との間に成立する発達層流の対流熱伝達に関するアナロジーについて、相似性の議論と数値計算で記述した。支配パラメータおよび軸方向無次元距離を、それぞれの流れに対して適正に用いた。それぞれの流れで2次パラメータが大きい場合、2つの流れの温度分布およびヌッセルト数は、支配パラメータ、プラントル数および軸方向無次元距離の同じ値に対して、近似的に同様であることを示した。, Analogy of convective heat transfer between developing laminar flows in curved pipes and orthogonally rotating pipes is described through similarity arguments and numerical computation. Governing parameters and a dimensionless axial distance are properly used for the respective flows. When the second parameter is large in each flow, it is shown that the temperature profiles and the Nusselt numbers of the two flows are approximately similar for the same values of the governing parameter, Prandtl number and the dimensionless axial distance., 資料番号: AA0001433048, レポート番号: NAL SP-37

航空宇宙技術研究所 26-28 Mar. 1997 東京 日本, National Aerospace Laboratory 26-28 Mar. 1997 Tokyo Japan, 燃焼科学技術に関する最近の数値計算の発展の影響力を概観した。燃焼技術への影響力は現段階では微々たるものに見えるが、しかし、数値計算技術は燃焼工学的アプローチを完全に変える可能性が大きい。考え得る変化の方向を、例を挙げて図解説明した。一方、燃焼科学においては、数値実験という新規の科学的アプローチを生み出し、数値実験が複雑な物理的化学的燃焼現象を理解するのに極めて優れていることが分かった。実際の実験に優る数値実験の利点を、例を挙げて説明した。次いで、克服すべき問題を論じた。最後に、将来の問題を明らかにした。, The impact of the recent advancement in numerical calculation on combustion science and technology will be reviewed. The impact on combustion technology seems insignificant at this stage, however it has a great potential to change the engineering approach completely. The possible direction of change will be illustrated by showing an example. In combustion science, on the other hand, it has generated a new scientific approach of numerical experiment, which has been proved to be very successful in understanding the physics and chemistry of complicated combustion phenomena. The advantages of numerical experiments over real experiments will be explained with some illustrative examples. Then the problems to be overcome are discussed. Finally, future problems will be identified., 資料番号: AA0001320023, レポート番号: NAL SP-36

航空宇宙技術研究所 26-28 Mar. 1997 東京 日本, National Aerospace Laboratory 26-28 Mar. 1997 Tokyo Japan, 本講演では乱流の研究に関して著者が現在まで関わってきた乱流の課題に対する研究活動の歴史を回顧し、今後の乱流研究に対する期待を述べた。従来から高速気流の研究に最大の関心を持っていることを述べた。乱流研究に関する夢として、非線形ナビエ・ストークス方程式の厳密解、すなわち一様流中に置かれた物体の周りの流れの厳密解への追及があることを述べ、計算前提条件の変遷の背景を説明した。コンピュータの進歩が乱流についての新しい物理モデルを生み出すことを期待した。, In this lecture, the history of author's own research activities on the various issues related to the turbulent flow is reviewed, and his expectations for the future studies on the turbulent flows are also presented. It is revealed that author has so far had the greatest interest in the study of high speed airflow. As one of his dreams, it is indicated to search the exact solution of non-linear Navier-Stokes equation, that is, the exact solution for the flow around an object placed in uniform flow, and the backgrounds of changes of major assumptions for calculation are interpreted. It is expected that a new physical model for the turbulent flow will be soon formulated with the future advancement in computation capacity., 資料番号: AA0001320007, レポート番号: NAL SP-36

シュレディンガー方程式をパーソナルコンピュータを用いて数値計算することによって,典型的な数種類の1次元井戸型ポテンシャル中を運動する粒子の波動関数,エネルギー,運動エネルギーおよび位置エネルギーを求めた。求めた波動関数の形とポテンシャルの形とを,エネルギーと共に,同一の図に図示することによって,量子論の特徴が視覚的かつ直感的に理解できることを示した。量子論と古典論とのつながり,エネルギーの増減の原因,分子形成の有様,固体の電子のエネルギーバンド形成の原因などが視覚的に理解されている。また,解析的には予測することが不可能な,特徴的な量子状態や現象が数値計算をすることによって初めて発見できる例を2,3示した。, The wave function, the energy, the kinetic energy and the potential energy of a particle moving in one-dimensional potentials of several typical quantum wells were obtained by calculating the Schrödinger equation with a personal computer. It was shown that we can visually and intuitively understand the characteristics of quantum mechanic by comparing the shape of wave function and the energy with the shape of potential. A visual interpretation is made on a relation between quantum mechanics and classical one, an origin of increase and decrease of energy, a condition of formation of molecules, an origin of formation of energy band structure for electrons in solid, and so on. It was also indicated that some kinds of characteristic quantum states can only be found by the numerical calculation.