電動機の大規模な三次元連成解析を可能とするため、磁気ビーズ法（Magnetic Beads Method:MBM）に粗密モデルを適用する。表面貼り付け型永久磁石電動機を対象として磁場・機構連成解析を行った結果、電動機の定格トルク値は、実機の測定結果と良く一致した。

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くりこみ群分子動力学（Renormalized Molecular Dynamics：RMD）法に対してエネルギー散逸項を付加することで粉粒体の計算機実験を可能とした．RMD 法を応用した粉粒体の計算機実験手法では RMD 法と同様にくりこみ変換の前後で相似な結果が得られるという特徴があり，安息角が一致することを確認した．さらに粉粒体の搬送や供給を行うスクリューフィーダーの計算機実験を実施し,流量や動力について理論式と比較し良く一致することを示す．

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Recently, a thermal power plant has been built near an existing wind firm. The pollutant emitted from the thermal power plant is affected by wind turbine at the wind firm, and the pollutant potentially disperses toward the ground surfaces. However, the effect of the wind turbine on the pollutant dispersion is less understood. In the present study, large-eddy simulation is implemented to investigate the effect of the wind turbine on pollutant dispersion at various rotating speeds. Arbitrary mesh interface technique is applied to represent the rotation of the wind turbine. The results show that the pollutant dispersion is strongly related to the rotating speed of the wind turbine, and as the rotating speed increases, the gas dispersion in the radial direction is enhanced.

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An offshore tower is used for measuring a wind velocity over a sea, but the tower affects the wind velocity and wind direction at the location of a sonic anemometer. It is, therefore, important to determinate an installation position of a sonic anemometer that is less affected by the tower. In the present study, large-eddy simulation is implemented to investigate the effect of the tower on the wind velocity at the location of the sonic anemometer. The wind velocity at the location of the sonic anemometer is slightly larger than the inflow velocity at any wind direction. In addition, the wind velocity of the sonic anemometer located at both the windward and downward direction is strongly affected by the tower.

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The physical background of the multiplicative decomposition will be considered and the definite conclusion that the rigid-body rotation must be included in the elastic deformation gradient will be provided in this article.

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This study conducts irreducible decomposition on the 6th-rank strain gradient elastic constants tensor A_ijklmn under the isotropic and centro-symmetric assumptions. The decomposition is based on the standard techniqes of group algebra: Schur-Weyl duality, Young tableaux and corresponding symmetrizers as the primitive idempotents. Present results reveal that the tensor A_ijklmn can be decoposed into three representations, A_ijklmn = A ^{6} _ijklmn + A ^{3,2,1} _ijklmn + A ^{4,2} _ijklmn, where A ^{6} _ijklmn and A ^{3,2,1} _ijklmn denote the generalized Cauchy solid condition and elastic null Lagrangian. The remaining A ^{4,2} _ijklmn has a close relation to the couple-stress elasticity.

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ナノ炭素材料であるグラフェンシート（GS）は優れた力学特性と電気特性を持つため，ナノ電子機械システムに応用することが期待されている．本研究では，GS の骨組モデルを用い，H¹勾配法，Phase-Field-Crystal 法，ボロノイ分割法及び分子動力学法と組み合わせることにより，最小振動固有値の最大化を目的とする GS の形状・構造二段階最適設計手法を開発する．

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本研究では、能動的パルスエコー法による欠陥同定に関する検討を行った。この方法では、材料に内在するき裂位置を推定するためにピエゾフィルムにパルス状電圧を加えることにより超音波を発振させ、き裂先端で反射する反射波をピエゾフィルムで受信する。受信波に対し時間反転法を適用し波のピークよりき裂先端を同定する。手法の有効性をシミュレーションによって検証し、またプローブの配置の影響がき裂位置の同定に及ぼす影響を調べた。

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Stress fields around a dislocation has been investigated within the framework of the first strain gradient elasticity. Dislocation is modeled by a continuous distribution of force dipoles which is implemented into the weak form equilibrium equation through the local body force. Numerical analysis is conducted on the basis of NURBS-based IGA where the cuboidal elastic domain Ω includes C¹ -class NURBS basis functions spanned by the 50 × 50 × 50 knots. Present analysis revealed that the stress fields around an edge dislocation show non-singular behaviours even at the center of the dislocation core.

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Pyrotechnic is used for the separation system of the rocket payload fairing. This system was utilized the fracture of the notched bolt of the titanium alloy using the pyrotechnic. However, the separation impact force using pyrotechnic is expected to decrease for enhancement of international competitiveness of rocket launch vehicle. In order to develop analytical methodology for impact fracture behavior of notched bolt and understand separation mechanism, the explicit calculations based on finite element methods were performed for test using Split-Hopkinson pressure bar method in the present study. The Johnson-Cook model, which represents visco-plasticity and high-temperature softening characteristics, was applied for titanium alloy. The computed result was good agreement with to the test result. In addition, it was confirmed that the impact force can be determined tension force until fracture on the notch surface. This methodology has possibility of effective tool for estimation of fairing separation force and development of lower impact system.

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In this work, the effects of chemical composition on shear moduli of random bcc Fe-Cu-X(X=Si/Ni/Mn) alloys were investigated as well as an increase of critical resolved shear stress by obstacles, Δτ . Shear moduli were calculated by first-principles calculations based on plane wave density functional theory. The chemical composition of bcc alloy was Fe_128−x−yCu_yX_x(X=Si/Ni/Mn) where x and y are x=0, 3, 6, 12, 18, 24, and y=0, 3, 6, 12, 18, 24, 36, 48, 60, such that 128 − x − y is more than 64. It is found that shear modulus decreases as Cu concentration or Ni concentration increases, it increases as Mn concentration increases, and the effect of Si is small in the FeCu, Fe-X binary alloys. It is also found that shear modulus increases as Cu concentration increases in Fe-Cu-X ternary alloys as a whole. The addition of Si atoms increases shear modulus in low Si density while it decreases shear modulus in high Si density. The addition of Ni atoms increases shear modulus. The addition of Mn atoms decreases shear modulus in low Cu density while it increases shear modulus in high Cu density. Δτ s were calculated by Russell-Brown model employing the equillibrium lattice constants and shear modulus which were obtained from the first-principles calculations. It is found that the trend of Δτ is oppsite from the trend of shear modulus due to Russell-Brown model. Δτ increases as Cu concentration or Ni concentration increases, the effects of Si concentration is small, and that Mn concentration is none in Fe-Cu, Fe-X binary alloys. Δτ increases as Cu concentration increases in Fe-Cu-X ternary alloys in general.

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This study investigates bending deformations of a two-dimensional periodic structure Ω whose unit cell is consisting of two straight beams. On the basis of micropolar elasticity and following numerical analysis by the Ritz method, we calculated the size-dependence of a local curvature of Ω, which is subjected to bending momentum and couple-stress, as a function of the size of the medium. The numerical analysis revealed that there is a critical size below which the classical scaling law fails to hold.

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分子動力学法を用いた，ラバルノズル内の流れ場解析を実施した．ラバルノズル内の流れを駆動するために，ラバルノズル入口と出口に境界条件の役割を果たす温度と圧力が任意の値に制御可能な熱浴を開発した．設置された熱浴により生じた圧力差で非平衡流れ場が駆動されることを確認した．また，得られたノズル内の温度，圧力分布が理論値と一致することを確認した．

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SPH(Smoothed particle hydrodynamics)を用いて平板片側貫通き裂の応力解析および表面半楕円き裂の進展解析を実施した．き裂先端における応力分布の特異性は SPH においても概ね良好に再現できた．き裂進展解析の結果，SPH では半楕円き裂が板厚を貫通する過程を滑らかに表現でき，実験結果に近いき裂面形状が得られた．

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融液成長中の Si 単結晶において固液界面近傍に発生する異方性熱応力は，育成する結晶直径の増加に伴い，Grown-in 欠陥の制御性に大きな影響を及ぼす．直径 300 mm の Si 結晶育成時における真性点欠陥の挙動に対する，この異方性熱応力の効果を，計算と実験の両面より調査した．また，この育成結晶に負荷される熱応力の大きさを，ヤング率と絡めて議論する．

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