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窪田 佳寛クボタ ヨシヒロ

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機械工学科
生体医工学研究センター
工業技術研究所
職名准教授
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Last Updated :2017/12/19

研究者基本情報

学位

  • 博士(工学), 東洋大学

研究活動情報

論文

MISC

  • 女性長距離アスリートに対するトータル的コンディショニングシステム構築と問題点, 岩本紗由美, 岩本紗由美, 杉田記代子, 杉田記代子, 鈴木哲郎, 鈴木哲郎, 太田昌子, 太田昌子, 窪田佳寛, 白石弘巳, 川口英夫, 川口英夫, 大上安奈, 大上安奈, 寺田信幸, 寺田信幸, 大熊廣一, 大熊廣一, 日本臨床スポーツ医学会誌, 24,   2016年10月01日
  • 粉砕棒を用いた土壌粉砕特性, 大石正行, 窪田佳寛, 望月修, 日本機械学会年次大会講演論文集(CD-ROM), 2016,   2016年09月10日
  • 非円形板の抵抗, 中島充博, 窪田佳寛, 望月修, 日本機械学会年次大会講演論文集(CD-ROM), 2016,   2016年09月10日
  • 突入抵抗に関する研究, 鈴木友也, 窪田佳寛, 望月修, 日本機械学会年次大会講演論文集(CD-ROM), 2016,   2016年09月10日
  • 葉脈のネットワーク構造, 佐藤慧拓, 窪田佳寛, 望月修, 日本機械学会論文集(Web), 82,   2016年
  • リンゴの袋掛けと強風落下との関係, 松本浩乃, 窪田佳寛, 大石正行, 望月修, 日本機械学会論文集(Web), 82,   2016年
  • 魚の尾ひれ形状に模した薄板による推力発生に関する研究, 中島充博, 窪田佳寛, 望月修, 日本機械学会論文集(Web), 82,   2016年
  • 自然やいのちと調和あるテクノロジーの開発 ‐共生ロボット技術によるヘルスケア‐, 寺田信幸, 窪田佳寛, 秋元俊成, 日本補綴歯科学会誌(Web), 8,   2016年
  • 自然やいのちと調和あるテクノロジーの開発, 寺田 信幸, 窪田 佳寛, 秋元 俊成, 日本補綴歯科学会誌, 8, (3) 223 - 228,   2016年,

     人の動きや無拘束計測により得られた人の心身状態の情報を基にロボットは移動し,ロボットの色を変化させ,音声合成技術を利用してロボットから話しかけるなど,インタラクティブに対応できる共生ロボットを作製した.共生ロボットが居住空間のインターフェイスとして働き,情報弱者である高齢者や見守りが必要なお年寄りにとって,やさしい生活環境が提供でき,健康管理も十分担えることを検証した.自然やいのちと調和あるテクノロジーの開発を目指して,高齢者および生活習慣病の予防を望む人たちが,無理なく使用できるヘルスケアシステムの開発にロボット技術とICTを導入し,人にやさしい生活環境の実現を目指した取り組みを紹介した.

  • 葉脈のネットワーク構造, 佐藤 慧拓, 窪田 佳寛, 望月 修, 日本機械学会論文集, 82, (833) 15 - 00386-15-00386,   2016年, Many features of organisms have the possibility that can be applied to the infrastructure and network system for the communication. From the previous studies, the network system of the venation is known as the strong network on the damage. This relates the structure of leaf vein. In this study, we are focusing on the network of leaf vein to understand the strong network system. First, we study the network structure to know the relation between damage on leaf and the strong network. Then, the influence of damage on leaf vein for the water absorption on the leaf was studied with the dye flow visualization. The result shows that the network type of vein on real leaf is the mesh type network. The mesh type network has the benefit to make a bypath when the vein has the damage. The result of dye flow visualization shows that the real leaf requires the single vein to make a bypath for damage region. The increasing of area on water absorbed relates the distance of water absorption. This means that number of vein is not dominant for the speed of water absorption. Therefore, the network of leaf vein has a high robustness from the damage of vein by the mesh type network.
  • 魚の尾ひれ形状に模した薄板による推力発生に関する研究, 中島 充博, 窪田 佳寛, 望月 修, 日本機械学会論文集, 82, (833) 15 - 00407-15-00407,   2016年, Purpose of this study is to investigate the relation between the shape of a thin plate and thrust force. The thin plate is what imitates the fish's caudal fin. We adopt an equilateral triangular, square, regular pentagon and hexagon as the shape of the plate. There are two ways of yielding thrust of fish; 1) drag-type as seen in flatfish and cod, and 2) lift-type as seen in tuna and shark. We focus on the drag-type fin, and consider reasons of different thrust with different shape of the fin. We simulate the reciprocal motion with some frequency of the plate as the fish tail at both situations in water being at rest and under a uniform flow. We measure the force acting on the plate directly, and consider the generating mechanism of the thrust due to the motion of the plate. To estimate force acting on the plate, we introduce the momentum consideration and the circulation of vortices due to the impulsive pressure of an edge of the plate starting suddenly. We discuss the relation between the shape of the plate and force due to the accelerating and decelerating motion of the plate in this paper. The most powerful shape of the fin is the triangular for an impulsive start. The spin parameter has to exceed 0.84 to produce the thrust force in the flow.
  • リンゴの袋掛けと強風落下との関係, 松本 浩乃, 窪田 佳寛, 大石 正行, 望月 修, 日本機械学会論文集, 82, (833) 15 - 00389-15-00389,   2016年, The typhoon often causes a serious damage of the apple before harvest. Many apples fall from trees by the strong wind. These apples are bagged to protect them from insects and control sun light for the apples coloring while they are ripening on the tree. We conceive that the wind-force acting on the bagging apple exceeds one without bag. Thus, we investigate the drag coefficient CD of the bagging apple by measuring drag force acting on an apple model experimentally. The shear stress on a stem under the typhoon is estimated for understanding one of mechanism for dropping apple due to the strong wind. The shear stress of a stem whose apple encounters the maximum velocity recorded at the past typhoon is estimated by the obtained CD. The drag force of the bagging apple becomes bigger than that of the apple without the bag. The bagging apple is not a rotational symmetry so that the CD is different with the different wind direction. The angle against the flow of model with the bag is changed from 0 deg. to 90 deg. to understand the influence of shape, since CD depends on the geometry. The shear force acting on the stem depends on the drag. Thus, the shear stress is larger if the drag is larger. The obtained shear stress is compared with allowable shear stress of a real tree. We suggest that there is possibility to decrease damage if we can decrease the drag of the bagging.
  • 魚の尾ひれ形状に模した薄板による推力発生に関する研究, 中島 充博, 窪田 佳寛, 望月 修, 日本機械学会論文集, 0,   2016年, Purpose of this study is to investigate the relation between the shape of a thin plate and thrust force. The thin plate is what imitates the fish's caudal fin. We adopt an equilateral triangular, square, regular pentagon and hexagon as the shape of the plate. There are two ways of yielding thrust of fish; 1) drag-type as seen in flatfish and cod, and 2) lift-type as seen in tuna and shark. We focus on the drag-type fin, and consider reasons of different thrust with different shape of the fin. We simulate the reciprocal motion with some frequency of the plate as the fish tail at both situations in water being at rest and under a uniform flow. We measure the force acting on the plate directly, and consider the generating mechanism of the thrust due to the motion of the plate. To estimate force acting on the plate, we introduce the momentum consideration and the circulation of vortices due to the impulsive pressure of an edge of the plate starting suddenly. We discuss the relation between the shape of the plate and force due to the accelerating and decelerating motion of the plate in this paper. The most powerful shape of the fin is the triangular for an impulsive start. The spin parameter has to exceed 0.84 to produce the thrust force in the flow.
  • 1317 群れの形状について, 毛利 紗和子, 窪田 佳寛, 望月 修, 流体工学部門講演会講演論文集, 2015,   2015年11月07日, The objective of this study is to understand the formation of school movement with the organism. Two factors relate the formation of school. One is the character of living things. The other is the stimulation from the environment. We numerically investigated the formation of school to change by influence of the character of living things and the stimulation from the environment. As a result we understand the relationship between the coefficient of restitution and formation of school movement.
  • 群れの形状について, 毛利紗和子, 窪田佳寛, 望月修, 形の科学会誌, 30,   2015年11月
  • 土の性状と浸透の関係, 豊田睦, 窪田佳寛, 望月修, 日本機械学会年次大会講演論文集(CD-ROM), 2015,   2015年09月12日
  • リンゴの袋掛けと強風落下との関係, 松本 浩乃, 窪田 佳寛, 大石 正行, 望月 修, 日本機械学会論文集, 0,   2015年, The typhoon often causes a serious damage of the apple before harvest. Many apples fall from trees by the strong wind. These apples are bagged to protect them from insects and control sun light for the apples coloring while they are ripening on the tree. We conceive that the wind-force acting on the bagging apple exceeds one without bag. Thus, we investigate the drag coefficient CD of the bagging apple by measuring drag force acting on an apple model experimentally. The shear stress on a stem under the typhoon is estimated for understanding one of mechanism for dropping apple due to the strong wind. The shear stress of a stem whose apple encounters the maximum velocity recorded at the past typhoon is estimated by the obtained CD. The drag force of the bagging apple becomes bigger than that of the apple without the bag. The bagging apple is not a rotational symmetry so that the CD is different with the different wind direction. The angle against the flow of model with the bag is changed from 0 deg. to 90 deg. to understand the influence of shape, since CD depends on the geometry. The shear force acting on the stem depends on the drag. Thus, the shear stress is larger if the drag is larger. The obtained shear stress is compared with allowable shear stress of a real tree. We suggest that there is possibility to decrease damage if we can decrease the drag of the bagging.
  • 葉脈のネットワーク構造, 佐藤 慧拓, 窪田 佳寛, 望月 修, 日本機械学会論文集, 0,   2015年, Many features of organisms have the possibility that can be applied to the infrastructure and network system for the communication. From the previous studies, the network system of the venation is known as the strong network on the damage. This relates the structure of leaf vein. In this study, we are focusing on the network of leaf vein to understand the strong network system. First, we study the network structure to know the relation between damage on leaf and the strong network. Then, the influence of damage on leaf vein for the water absorption on the leaf was studied with the dye flow visualization. The result shows that the network type of vein on real leaf is the mesh type network. The mesh type network has the benefit to make a bypath when the vein has the damage. The result of dye flow visualization shows that the real leaf requires the single vein to make a bypath for damage region. The increasing of area on water absorbed relates the distance of water absorption. This means that number of vein is not dominant for the speed of water absorption. Therefore, the network of leaf vein has a high robustness from the damage of vein by the mesh type network.
  • 筋電計サンプリングレートの違いがブラキシズムイベントの検出能に及ぼす影響, 佐藤雅介, 佐藤雅介, 大塚英稔, 飯塚知明, 渡邉明, 岩瀬直樹, 猪野照夫, 窪田佳寛, 寺田信幸, 斉藤小夏, 菅原絹枝, 藤澤政紀, 日本顎口腔機能学会雑誌, 21, (1) 28 - 33,   2014年09月30日, 我々は,これまでに携帯型筋電計バイオフィードバック装置の開発,その有用性を報告してきた.しかしながら,携帯型筋電計は日中の測定を対象としており,小型化を優先して開発されたことから,サンプリングレートが4Hz~64Hzとなっている.そのため,持続時間の短い筋電図波形の測定に対しては信頼性を検証する必要がある.本研究では,携帯型筋電計で測定した筋電図の検出能を検証することを目的とし,夜間にポリソムノグラム(PSG)との同時測定を行い,サンプリングレートの違いがブラキシズムイベントの検出に及ぼす影響について検討した.夜間の歯ぎしりを指摘されたことのある成人男性3名(平均年齢22.7±0.6歳)を被験者とし,夜間睡眠時の筋電図波形から得られたブラキシズムイベントを,Phasic型,Tonic型,Mixed型に分類し,それぞれのイベント数を算出した.その後,PSGから得られたイベント数を基準として携帯型筋電計から得られたイベント数の検出率を求めた.Tonic型のイベント数は携帯型筋電計とポリソムノグラムの両者ともほぼ同様の値を示しており,検出率は94.1%であった.一方,Phasic型と Mixed型のイベント数における検出率は80.0%と83.3%であった.以上の結果から,サンプリングレートの違いはTonic型イベントの検出には大きく影響しないことが示された.
  • 1318 生物の逃避行動観察, 宇田川 智裕, 窪田 佳寛, 望月 修, 流体工学部門講演会講演論文集, 2015,   2015年11月07日, The objective of this study is to observe the escape response of flies. Their turning speed is very fast. We developed a system to observe the fast movement. The details of development is used two galvano mirror and high speed camera in this system. The moving speed of the object it is possible to observe up to 250mm/s. The details of development of two galvano mirror and high speed camera in this paper. It shows the state of movement of the flies captured using a system developed and the developed system.
  • J0260205 土の性状と浸透の関係, 豊田 睦, 窪田 佳寛, 望月 修, 年次大会 : Mechanical Engineering Congress, Japan, 2015,   2015年09月13日, We investigate the infiltration flow in a soil-model to understand the influence of grain size of a soil. The soil model consists of glass beads between two thin glass plates. We visualized the infiltration flow with this model. We carried out the experiment with the different diameters of glass beads for the model. We use five types of different diameters on glass beads whose diameters are similar to those of real sand constituting a soil. The results show that the vertical velocity in d = 1.3mm of diameter on glass beads is the maximum for infiltration. The diameter d = 0.10mm of glass bead gives wider infiltration than the bigger ones. The direction of infiltration relates the ratio between volume on void of soil model and volume of supplied water. The wider infiltration flow causes when the volume flow rate is larger or grain of soil is smaller.
  • 筋電計サンプリングレートの違いがブラキシズムイベントの検出能に及ぼす影響, 佐藤 雅介, 大塚 英稔, 飯塚 知明, 渡邉 明, 岩瀬 直樹, 猪野 照夫, 窪田 佳寛, 寺田 信幸, 藤澤 政紀, 日本顎口腔機能学会雑誌, 21, (1) 62 - 63,   2014年
  • 突入物体の表面性状とスプラッシュ, 横山 真男, 窪田 佳寛, 望月 修, 理論応用力学講演会 講演論文集, 60, (0) 240 - 240,   2011年, 本研究では、表面性状の違いによる抵抗低減効果の検証の一環として、物体表面のゲル化によるスプラッシュへの影響を調査した。評価として、実験にはアクリル製の球体とゲル素材の球体を水面へ落下させる現象について、ハイスピードカメラによる録画観察と、粒子法(MPS)による数値シミュレーションを用いて、スプラッシュの形状と周囲流体の速度を比較検証した。ゲル球によるスプラッシュの到達点の最大値は最初のスプラッシュ(Primary Splash)は膨潤度が上昇しても変わらなかったが、物体が沈みその後に発生した二度目のスプラッシュ(Secondary Splash)は膨潤度があがるにつれて増えた。また、膨潤度があがるにつれて水中での物体の落下速度も上がっていた。
  • GS10 ビーズ間の流れ, 豊田 睦, 窪田 佳寛, 望月 修, 流体工学部門講演会講演論文集, 2014,   2014年10月25日, We study the infiltration flow in a soil-model. Our question is how the flow decides the direction under the soil. The soil model consists of glass beads between two thin glass plates. We use 2.0mm diameters of glass beads whose diameters is similar to real sand constituting a granule. The meandering is typical flow pattern of the infiltration. The precursor of the flow direction is observed of the front edges of the flow by using the image processing. It is a thin film on the plates. The influence of single bead for meandering flow is studied. The angle between the center of bead and the front edge of droplet is measured when the droplet puts on a bead gently. The angle changed with the diameter of bead.
  • S054021 加速する三次元物体の抵抗係数([S05402]噴流,後流,およびはく離流れの基礎と応用:最前線(2)), 菊地 謙次, 今野 友博, 市川 誠司, 窪田 佳寛, 望月 修, 年次大会 : Mechanical Engineering Congress, Japan, 2011,   2011年09月11日, The purpose of this study is to analyze the drag coefficient of three dimensional objects in accelerated motions. The drag coefficient of the fundamental objects are usually observed under steady flow. Many researchers have expressed the effect of unsteadiness by an added mass or impulse force, however the unsteady drag coefficient has not been known yet. The free-fall sphere was observed by using a high-speed camera and the time-varying of its speed was analyzed by a motion capture method. The range of Reynolds number of falling sphere was from zero up to 105. The vortex generation and shedding were observed by means of the dye visualization of wake structure. The change in drag of falling sphere was obtained from the change in acceleration. The unsteady drag coefficients were found 108 times higher than the steady drag coefficients in this experiment. Furthermore, the unsteady drag coefficients were tend to close to 0.44 which is the steady coefficient of sphere on corresponded Reynolds number based on the terminal velocity.
  • 0531 突入物体の非定常後流形成, 窪田 佳寛, 望月 修, 流体工学部門講演会講演論文集, 2014,   2014年10月25日, The objective of this study is to understand the influence of body impinging to the water surface. Our question is how will the fluid be moved with the body impinging. The spherical body used in the experiment. The flow was visualized with two methods. One is the visualized with digital camera to observe the path line by using long exposure technique. The other is using high speed CMOS camera. The combining of these techniques has two advantages. One is high spatial resolution, and the other is high time resolution. The results show that the path line indicates two phases of flow formed by impingement of body. One, the fluid moved with the body entering the water by a hill's vortex like flow. Two, the fluid moved with deformation of water surface by formation of water splash. The potential like flow formed with the flow impulsively accelerated by the body impingement.
  • 1806 物体の表面性状の違いが周辺流れ場へ与える影響(OS18.流体の数値計算手法と数値シミュレーション(2),OS・一般セッション講演), 横山 真男, 窪田 佳寛, 望月 修, 計算力学講演会講演論文集, 2011, (24) 545 - 546,   2011年10月08日, We investigated splash produced by spherical object plunging to water surface. We focused on the effect of swelling of object which was made of hydro gel. We compared the splash versus of swelling of the object. The splash form we observed was crown-type that is formed by water jets with many droplets. The height of splash became higher as swelling increased, and the speed of the object sinking in the water also became higher. The velocity around the object increased according to swelling. The gel surface of object was effective for the reduction of friction of an object moving in liquid.
  • 1201 果実周りの流れ, 松本 浩乃, 窪田 佳寛, 望月 修, 流体工学部門講演会講演論文集, 2014,   2014年10月25日, The typhoon makes a serious damage to the apple farmer by dropping apple before the harvest due to the strong wind. We investigated the drag coefficient C_D of apple models. We are focusing on the influence of the bag to cultivate the delicious fruit. The C_D was obtained in experimentally with or without bag. The drag force and the shear stress of stem under the condition of typhoon were determined from the obtained C_D. The drag force increased with using a bag, so that the shear force acting on model also increased. The obtained shear stress was compared with allowable shear stress of real tree. The direction of bag realizes the shear stress less than the allowable value. Thus, the dropping apple due to strong wind can decrease with the suitable shape of bag to decrease the drag force.
  • 8G36 魚の尾鰭形状と推進力に関する研究(OS26 機械工学におけるバイオミメティクス研究1), 工藤 裕司, 菊地 謙次, 窪田 佳寛, 望月 修, バイオエンジニアリング講演会講演論文集, 2012, (24) "8G36 - 1"-"8G36-2",   2012年01月06日
  • S0510103 尾ひれまわりの流れ([S051-01]噴流,後流およびはく離流れ現象の探求と先端的応用(1),流体工学部門), 上原 裕介, 菊地 謙次, 窪田 佳寛, 望月 修, 年次大会 : Mechanical Engineering Congress, Japan, 2014,   2014年09月07日, There are various shapes in the tail fin of fish in nature. The way to use of tail fin should differ by shapes. In this study, we aimed to determine the relationship between thrust generation and fish fin shape. To compare the effect of fin shape had on thrust generation, we categorized the morphological shapes of fish fins into equilateral polygonal shapes. Polygonal fins were used to generate thrust that depended only on shape. These fins were constructed of a hard elastic material to eliminate any influence of shape deformation. A servomotor with a reciprocal rotation moved a fin cyclically, and thrust was experimentally measured using a strain gage system. We experimented in static fluid and uniform flow. In static fluid, thrust tended to be proportional to the inertia moment of a fin, which indicated difficulty with rotation. Moreover, this trend for thrust generation was directly related to the length of the perimeter of a polygonal fin. In uniform flow, thrust is reduced relative to the static fluid. Highest thrust was generated by the diamond shape.
  • 8G37 直列円錐群まわりの流れの可視化(OS26 機械工学におけるバイオミメティクス研究1), 四元 大, 菊地 謙次, 窪田 佳寛, 望月 修, バイオエンジニアリング講演会講演論文集, 2012, (24) "8G37 - 1"-"8G37-2",   2012年01月06日
  • カエルの飛び込みに学ぶスプラッシュの形成, 窪田 佳寛, 工業技術 : 東洋大学工業技術研究所報告, (36) 84 - 87,   2014年
  • 1206 スプラッシュエロージョンに関する研究(OS12 生物・生体に関する流れ,OS12 生物・生体に関する流れ), 窪田 佳寛, 豊田 睦, 望月 修, 流体工学部門講演会講演論文集, 2013,   2013年11月09日, The objective of this study is to understand the process of splash erosion due to impacting of raindrop onto soil. This is investigated experimentally using a high speed CMOS camera. To understand the phenomena qualitatively, the soil model was developed. The model simulates the fine sand where the diameter of soil particle is 0.1mm. A dent was formed by the impact of droplet on the soil. The droplet deformed with the impacting, and formed the film-flow. The suspension of soil particle was caused with the shear force due to the film-flow. The suspended particle was not entrained into film-flow. The suspended particle was initially settled beside the film-flow. Thus, the suspended particle was not wet.
  • 1D07 魚の尾鰭形状と推進力に関する研究(OS10-2:生物の遊泳と飛翔(2)), 上原 裕介, 菊地 謙次, 窪田 佳寛, 望月 修, バイオエンジニアリング講演会講演論文集, 2013, (25) 123 - 124,   2013年01月08日
  • スプラッシュエロージョンに関する研究, 窪田佳寛, 豊田睦, 望月修, 日本機械学会流体工学部門講演会講演論文集(CD-ROM), 91st,   2013年
  • 物体壁面の表面性状を考慮した流れのシミュレーション, 横山真男, 菊地謙次, 窪田佳寛, 望月修, ながれ, 32, (4) 319 - 326,   2013年08月25日, これまで多くの流れのシミュレーションは,物体と流体の間の境界条件は滑り無しで計算されてきた.しかし,物体表面の性状によっては,一概に滑り無し条件では適切な結果が得られない場合もある.一例として,魚類や両性類の体表にはヌメリや滑りがあるが,その為にこれまでの滑り無し壁面とは異なる流れが観察され,この滑りといった表面性状の効果を計算に導入する必要がある.本研究では,境界条件に滑りを考慮に入れることで,その様な滑りのある物体を表現する方法を提案し,粒子法(MPS法)による流れのシミュレーションを行った.検証については,生体材料の1つであり水触媒の高分子ゲルであるハイドロゲルを用いて,ポアズイユ流れ及びスプラッシュの実験と比較し,シミュレーション結果が実験のそれらをよく表現できたことを確認した.
  • カエルの飛び込みに学ぶスプラッシュの形成, 窪田 佳寛, 工業技術 : 東洋大学工業技術研究所報告, (36) 84 - 87,   2014年
  • 0701 蛙の跳び込みに伴うスプラッシュの形成(OS7 生物・生体に閧する流れ,オーガナイズドセッション), 窪田 佳寛, 菊地 謙次, 望月 修, 流体工学部門講演会講演論文集, 2012,   2012年11月16日, The objective of this study is to understand the formation of water splash by the frog diving into water.Splash formation by the frog diving was investigated by using high speed camera.The characteristics of frog diving were studied with model experiments.The model experiments obtained the influence of both body shape and hydrophihcity as surface condition.Body shape was investigated with the influence of tail shape of body and NACA 0012 airfoil in cross-section.Frog diving caused the small water splash formation with air cavity under the water.The formation of splash was related to the film-flow caused by body impacted to water surface.The fore limb of frog set along the body during the dive.This is the reason to inhibit the formation of separation of film-flow.The strong hydrophihc body of frog was caused film separation.
  • 1411 水面に突入する物体表面の滑りを考慮したスプラッシュのシミュレーション(OS14-3.メッシュフリー/粒子法とその関連技術(3),OS・一般セッション講演), 横山 真男, 窪田 佳寛, 矢川 元基, 望月 修, 計算力学講演会講演論文集, 2012, (25) 235 - 236,   2012年10月06日, The purpose of this study is to understand the phenomenon of splash, taking account of the hydrophilic and hydrophobic properties of an object through the numerical simulation. The splash generated by a sphere object with different properties diving into water is simulated by using the Moving Particle Semi-implicit (MPS) method. It is shown the degree of swelling of hydrogel influences the slip on the surface of an object. In order to simulate the splash generated by an object made of hydrogel, we installed the effect of swelling degree to the calculation on the surface of object. We show the hydrophilicity affected the shape of splash and the velocity of flow near the object was increased with the swelling degree.
  • S053046 加速する三次元物体の抵抗係数, 今野 友博, 菊地 謙次, 市川 誠司, 窪田 佳寛, 望月 修, 年次大会 : Mechanical Engineering Congress, Japan, 2012,   2012年09月09日, The purpose of this study is to know differences between steady and unsteady drag coefficients of a sphere. Though we often have to estimate unsteady drag-forces acting on a moving obstacle, we are obliged to use the well-known steady drag coefficient for the first estimation because of lack of information about effects of unsteadiness on the drag coefficient. The usual way to take account of unsteadiness is an added mass. However, its application is restricted within the simple shape of an obstacle. We propose a way based on the equation of motion to obtain the unsteady drag coefficient. To confirm validity of the way, we measured and analyzed the motion of the falling sphere in water by using a high-speed camera and a motion capture method. The drag coefficients as a function of time were obtained by substituting measured values of velocity and acceleration into the equation of motion. The drag coefficient was 0.52 when the sphere attains the terminal velocity, being quite large at the beginning of motion. Comparing with the values obtained by the other previous studies, our result is reasonable.
  • G010025 突入物体の表面性状を考慮したスプラッシュの数値シミュレーション, 横山 真男, 窪田 佳寛, 望月 修, 年次大会 : Mechanical Engineering Congress, Japan, 2012,   2012年09月09日, The splash generated by a sphere with these properties diving into water was simulated by using the Moving Particle Semi-implicit (MPS) method. The difference of the properties is described by the strength of interaction between the particles that represent respectively the solid surface and water. The strength is adjusted so that results coincide with the experimental ones under the same conditions. In the case of the sphere made of acrylic resin the thin film-flow rising along the surface of the object was observed in the moment that the sphere contacts the water surface In order to simulate the film-flow with the MPS method, the Van der Waals force and Coulomb force were introduced to our simulation as the analogical force acting on the interface between object and water. The simulation result showed good agreement with the experimental ones.
  • 水中を落下する球に作用する非定常抵抗の係数, 菊地謙次, 今野友博, 市川誠司, 窪田佳寛, 望月修, 日本機械学会論文集 B編(Web), 79, (798) WEB ONLY 151-163 - 163,   2013年, The purpose of this study is to know differences between steady and unsteady drag coefficients of a sphere. Though we often have to estimate unsteady drag-forces acting on a moving obstacle, we are obliged to use the well-known steady drag coefficient for the first estimation because of lack of information about effects of unsteadiness on the drag coefficient. The usual way to take account of unsteadiness is an added mass. However, its application is restricted within the simple shape of an obstacle. We propose a way based on the equation of motion to obtain the unsteady drag coefficient. To confirm validity of the way, we measured and analyzed the motion of the falling sphere in water by using a high-speed camera and a motion capture method. The drag coefficients as a function of time were obtained by substituting measured values of velocity and acceleration into the equation of motion. The drag coefficient was 0.52 when the sphere attains the terminal velocity, being quite large at the beginning of motion. Comparing with the values obtained by the other previous studies, our result is reasonable.
  • 1302 突入物体の表面性状とスプラッシュ(OS13-1 流れの抵抗低減,オーガナイズドセッション), 横山 真男, 窪田 佳寛, 望月 修, 流体工学部門講演会講演論文集, 2010,   2010年10月29日, We investigated splash produced by spherical object plunging to water surface. We focused on the effect of swelling of object. We compared the splash versus of swelling of gel object surface. The splash form we observed was crown-type that is formed by water jets with many droplets. The height of splash became higher as swelling increased, arid the speed of gel object sinking down in the water also became higher. The gel surface of object was effective for the reduction of friction of an object moving in liquid.
  • 物体壁面の表面性状を考慮した流れのシミュレーション, 横山 真男, 菊地 謙次, 窪田 佳寛, ながれ : 日本流体力学会誌 = Nagare : journal of Japan Society of Fluid Mechanics, 32, (4) 319 - 326,   2013年08月
  • 物体の先頭形状が及ぼすスプラッシュ形成への影響, 窪田佳寛, 望月修, 可視化情報学会誌, 29, (Suppl.2) 201 - 202,   2009年10月15日
  • 魚の尾鰭形状と推進力に関する研究, 上原裕介, 菊地謙次, 窪田佳寛, 望月修, バイオエンジニアリング講演会講演論文集, 25th,   2013年01月08日
  • 物体先頭形状がスプラッシュへ与える影響(解析・予測・制御 流体計測・実験法(1),一般講演), 窪田 佳寛, 望月 修, 日本流体力学会年会講演論文集, 2009,   2009年09月02日, We investigated splash produced by a rigid body impacting water. There are many factors related to splash formation, but we focused on effect of head-shape on splash of Type-II in this paper. The Type-II splash is one formed by film-flow running along the surface of the head. Thus, it is influenced by the head-shape. We compared with splashes of a) hemisphere-, b) cylinder- and c) cone-heads. It was found that there was no ripple on surface of the air cavity formed by the cone-head body. Contraction of the air cavity after separation from the body made splash sharp. The sharp splash affected the Type-II splash.
  • 魚の尾鰭形状と推進力に関する研究, 工藤裕司, 菊地謙次, 窪田佳寛, 望月修, バイオエンジニアリング講演会講演論文集, 24th (CD-ROM),   2012年01月06日
  • 水面への物体突入時にできるスプラッシュ(流体計測・実験(1),一般講演), 宇山 遼一, 窪田 佳寛, 望月 修, 日本流体力学会年会講演論文集, 2008,   2008年09月04日, Splash generated by a sphere plunging into water water was investigated experimentally. Splash was classified into three types according to the impact velocity, ν_i, of the sphere on water surface. A thin cone type of splash was observed when ν_i<0.21m/s. Small droplets were broken out in the upward direction from the tip of the cone. A thick cone with scattered droplets was observed when 0.21<ν_i<4.18m/s. Water crown with droplets separated from the tip of fingers was formed when ν_i>4.18m/s. Sequence of these splashes was presented and discussed in this paper.
  • 直列円錐群まわりの流れの可視化, 四元大, 菊地謙次, 窪田佳寛, 望月修, バイオエンジニアリング講演会講演論文集, 24th (CD-ROM),   2012年01月06日
  • 蛙の跳び込みに伴うスプラッシュの形成, 窪田佳寛, 菊地謙次, 望月修, 日本機械学会流体工学部門講演会講演論文集(CD-ROM), 90th,   2012年
  • 細胞の運動モデル(OS16d 生体力学における新しい計算解析手法), 窪田 佳寛, 望月 修, 計算力学講演会講演論文集, 2004, (17) 197 - 198,   2004年11月17日
  • 濃度差によってスポンジを透過する流れについて, 豊田睦, 菊地謙次, 窪田佳寛, 望月修, 可視化情報学会誌, 31, (Suppl.2) 103 - 104,   2011年09月13日
  • カエルの行動の可視化, 田口綾乃, 窪田佳寛, 菊地謙次, 望月修, 可視化情報学会誌, 31, (Suppl.2) 101 - 102,   2011年09月13日
  • 運動性細胞モデル(J07-1 生物の運動機能/バイオミメティクスとバイオメカニクス/バイオロボティクスとバイオメカトロニクス(1),J07 生物の運動機能/バイオミメティクスとバイオメカニクス/バイオロボティクスとバイオメカトロニクス), 窪田 佳寛, 望月 修, 年次大会講演論文集 : JSME annual meeting, 2004, (6) 137 - 138,   2004年09月04日, Objective of this study is to understand dynamics of amoeboid cells through a numerical simulation of motion. Cell structures are represented by a mass-spring-dashpot system presenting a cell membrane, cytoskeletal filaments and internal net structure constructed by intermediate filamnets. These structures are distinguished by stiffness, damping coefficient and mass of the system. Frequency response to forcing for different cases is shown in this paper. This model is effective to show the similar motion as that of amoeboid cells.
  • 加速する三次元物体の抵抗係数, 菊地謙次, 今野友博, 市川誠司, 窪田佳寛, 望月修, 日本機械学会年次大会講演論文集, 2011 (CD-ROM),   2011年09月10日
  • 物体の表面性状の違いが周辺流れ場へ与える影響, 横山真男, 窪田佳寛, 望月修, 日本機械学会計算力学講演会論文集(CD-ROM), 24th,   2011年
  • 535 微小通路内における蟻の運動特性観察, 窪田 佳寛, 望月 修, 年次大会講演論文集 : JSME annual meeting, 2003, (5) 83 - 84,   2003年08月05日, Object of this study is to conjecture a motion of a micro robot moving in a blood vessel. Instead of the micro robot, we observed motion of legs of an ant walking along a conduit. The motion of an ant was taken by a high speed video camera. The change in position of legs were analyzed and the change in speed and acceleration were obtained. It was found that each legs were synchronized and rear leg was the most powerful.
  • 親水性物体が及ぼすスプラッシュ形成への影響, 窪田佳寛, 稲葉利彦, 望月修, 可視化情報学会誌, 30, (Suppl.2) 27 - 28,   2010年10月15日
  • 突入物体の表面性状とスプラッシュ, 横山真男, 窪田佳寛, 望月修, 日本機械学会流体工学部門講演会講演論文集(CD-ROM), 88th,   2010年
  • 細胞の運動モデル, 窪田佳寛, 望月修, 日本機械学会計算力学講演会講演論文集, 17th,   2004年11月17日
  • 細胞の運動シミュレーション, 窪田佳寛, 望月修, 数値流体力学シンポジウム講演論文集(CD-ROM), 18th,   2004年