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Seamless analysis from the DC to microwave frequencies is difficult task but essential to modern sub-micron integrated devices from the viewpoint of electromagnetic compatibility, in particular ELF and SAR problems to the human body. In this paper, we propose a new quasi-analytical approach taking the displacement current into account, for the full frequency analysis. Target conductive region can be subdivided into small cylindrical conductors having a simple geometrical shape. Because of the simple geometrical shape, it is possible to calculate an each of the resistances, inductances and capacitances of the subdivided conductors. This leads an equivalent circuit of the devices. Solving this equivalent circuit makes it possible to compute the electromagnetic field distributions exhibiting resonance phenomena. This paper applies our quasi-analytical approach to a simple finite length solenoid inductor. As a result, full wave solution reflecting on the practical frequency characteristics of the solenoid inductor could be obtained.

長崎大学学位論文 [学位記番号]博（工）甲第57号 [学位授与年月日]平成30年5月16日, (2018-05-16)

The film boiling heat transfer around a vertical finite-length cylinder to saturated liquid was analyzed by taking into account each convective heat transfer on the three surfaces (bottom, side and top) of isothermal cylinder. The bottom is convex and conical. The vapor-liquid interface for the conical bottom surface and vertical lateral surface of the cylinder are assumed to be smooth. The connection condition of the vapor film between the conical bottom and the vertical lateral surface is given by the continuity of vapor flow rate around the lower end of the vertical lateral surface. The analytical result was compared with that of the vertical finite-length cylinder with a convex hemispherical bottom., 長崎大学工学部研究報告, 41(76), pp.20-27; 2011

The film boiling heat transfer around a vertical silver cylinder with a convex hemispherical bottom was investigated experimentally for quiescent water at atmospheric pressure. The experiments have been carried out by a quenching method. The diameter and length of test cylinder are 32mm and 48mm, respectively. The test cylinder was heated to about 600℃ in an electric furnace and then cooled in saturated or subcooled water with the immersion depth of about 100mm. The degree of liquid subcooling was varied from 0K to 30K. The analytical solutions for saturated and subcooled boiling are obtained by applying the two-phase boundary layer theory for the vapor film with the smooth interface. The experimental data can be correlated within ±15% by the present prediction method. Also, the lower limit of film boiling was examined in terms of wall heat flux and degree of superheating., 日本機械学會論文集. B編, 75(756), pp.1649-1654; 2009

Correlating equations for the film boiling heat transfer from a vertical cylinder of finite-length to subcooled liquids were examined. The overall heat transfer rate around the cylinder was determined by taking into account each convective heat transfer on the bottom, side and top surfaces of the cylinder. The present prediction method was compared with the experimental data obtained by quenching method. The experimental data can be correlated within +15%～-40% by the present prediction method., 長崎大学工学部研究報告 Vol.35(64) p. 1-10, 2005

The effect of liquid subcooling on the film boiling heat transfer from a vertical finite-length silver cylinder was investigated experimentally for water at atmospheric pressure. The experiments have been carried out by a transient method, i. e., quenching method. The diameter and length of the cylinder used in the experiment are, respectively, 45mm and 45mm. The liquid subcooling was varied from 2 to 20K. As a result, the average heat flux increases with an increase in liquid subcooling. The film boiling heat transfer was enhanced by 15 to 220% with an increase in liquid subcooling. The minimum heat flux increases linearly with liquid subcooling., 長崎大学工学部研究報告 Vol.31(57) p.41-46, 2001

The film boiling heat transfer from a vertically placed cylinder of finite-length was analyzed to predict the overall heat transfer rate around the cylinder in terms of boiling curve. The overall heat transfer rate around the cylinder was determined by taking into account every convective heat transfer on the bottom, side and top surfaces of the cylinder. The local heat transfer rate on the bottom surface was analyzed by the method similar to that developed by the authors for a downward-facing horizontal circular plate. For the vertical lateral surface of the cylinder, Bromley's model and the vapor-film-unit model presented by Nishio and Ohtake were introduced. Bromley's model is effective for the smooth interface, while the vapor-film-unit model is effective for the wavy interface. Bromley's model was modified to accommodate the continuity of the vapor flow rate at the lower end of the side wall, where the vapor film had a finite thickness due to the vapor inflow out of the bottom surface. Berenson's model was adopted on the top surface. The effects of length and diameter of the cylinder on the overall heat transfer rate were discussed in terms of boiling curve. The new prediction method was compared with the experimental data obtained by the authors., 長崎大学工学部研究報告 Vol.29(53) p.181-186, 1999

Quenching experiments on the transient film boiling heat transfer from a vertical silver cylinder to a quiescent saturated water at atmospheric pressure have been carried out in the wide ranges of the length (8mm to 160mm) and the diameter (8mm to 100mm) of cylinder. The test cylinder was heated to 600℃ by an electric furnace and then cooled at the immersion depth of about 100mm. The effect of aspect ratio (length-to-diameter ratio) on the lower limit of film boiling for saturated water was discussed. The prediction method was proposed., 長崎大学工学部研究報告 Vol.32(58) p.69-73, 2002

The film boiling heat transfer from a vertically placed cylinder of finite-length was analyzed to predict the overall heat transfer rate around the cylinder in terms of boiling curve. The overall heat transfer rate around the cylinder was determined by taking into account every convective heat transfer on the bottom, side and top surfaces of the cylinder. The local heat transfer rate on the bottom surface was analyzed by the method similar to that recently developed by the authors for a downward-facing horizontal circular plate. For the vertical lateral surface of the cylinder Bromley's model was modified to accommodate the continuity of the vapor flow rate at the lower end of the side wall, where the vapor film had a finite thickness due to the vapor inflow out of the bottom surface. Berenson's model was adopted on the top surface. The effects of length and diameter of the cylinder on the overall heat transfer rate were discussed in terms of boiling curve and the present prediction method was compared with the experimental data obtained by the authors. The heat transfer correlation equation can correlate within 10 percents the experimental data obtained under the quenching condition.

The film boiling heat transfer from a vertically placed cylinder of finite-length was analyzed to predict the overall heat transfer rate around the cylinder in terms of boiling curve. The overall heat transfer rate around the cylinder was determined by taking into account every convective heat transfer on the bottom, side and top surfaces of the cylinder. The.local heat transfer rate on the bottom surface was analyzed by the method similar to that recently developed by the authors for a downward-facing horizontal circular plate. Bromley's model for the vertical surface was modified to accommodate the continuity of the vapor flow rate at the lower end of the side wall, where the vapor film had a finite thickness due to the vapor inflow out of the bottom surface. Berenson's model was adopted on the top surface, independent of the vapor flowing upward along the side wall. The effects of length and diameter of the cylinder on the overall heat transfer rate were discussed in terms of boiling curve and the present prediction method was compared with the experimental data obtained by the authors., 長崎大学工学部研究報告 Vol.26(47) p. 145-153, 1996

Quenching experiments on the transient film boiling heat transfer from a vertical cylinder to a quiescent saturated water at atmospheric pressure have been carried out in the wide range of the length and the diameter of the cylinder. The test cylinders used in the experiments are made of silver. The test cylinder was heated to 600℃ by an electric furnace and then cooled with the immersion depth of 80mm to 100mm. Experimental data were presented in terms of both cooling curve and boiling curve for the case of 8,15,32 and 50mm diameter cylinders with the length ranging from 8mm to 64mm and for the case of 8,16,32 and 64mm length cylinders with the diameter ranging from 8mm to 50mm. The effects of length and diameter of the cylinder on the overall heat transfer rate were discussed in terms of boiling curve., 長崎大学工学部研究報告 Vol.28(51) p.139-142, 1998

Johnston-Gilman型塑性流動関数を導入した軟鋼の構成方程式および転位の熱活性化過程にもとづく塑性流動関数を導入した実用高強度Al合金の構成方程式の両者について,有限長棒の高速引張りの挙動が有限要素法により解析され,波頭における鋭い応力ピークの存否など動的挙動における両者の差異が明らかにされた., Using the constitutive equations of a mild steel that introduced the plastic flow function of Johnston-Gilman type and of high strength Al alloys that introduced the plastic flow function basing upon thermal activation process of dislocation, the behaviours of bars of finite length are analysed by finite element method. The differences between these two cases such as the existence and non-existence of sharp stress peak in wave front, are clarified., 資料番号: SA0125650000

航空機のうける衝撃負荷速度が速くなると弾塑性波による応力やひずみの局在が問題になってくる,本論文では,この分野の問題のうち,最も基本的でしかもまだ解かれていなかった問題として,弾-ε^n硬化材有限長棒の高速引張りを取扱う.ひずみ速度不依存型の塑性波理論により特性曲線法を用いて解かれた.その結果は,破断伸び-引張り速度関係について述べれば,剛-直線的加工硬化材または弾-直線的加工硬化材有限長棒の場合と周期性が同じの鋸歯状挙動を示すが,鋸歯の先端が丸くなっている点が異なることを示す.すなわち,ひずみ速度不依存の構成方程式の場合には,いずれにしても静的より脆く挙動することになる., 資料番号: SA0125504000

Article, 信州大学纎維学部研究報告 3: 48-56(1953)

Correlating equations for the film boiling heat transfer from a vertical cylinder of finite-length to atmospheric subcooled water were examined and proposed. The overall heat transfer rate around the cylinder was determined by taking into account each convective heat transfer on the bottom, side and top surfaces of the cylinder. The present prediction method was compared with the experimental data obtained by quenching method. The diameter (D) and length (L) of the cylinder tested in the experiments are 32 mm×16 mm, 32 mm×32 mm, 32 mm×64 mm, 45 mm×45 mm, 50 mm×16 mm, 50 mm×32 mm and 50 mm×64 mm. The degree of liquid subcooling was varied from 2 to 30 K. All the experimental data for the aspect ratio with 0.32⪇L/D⪇2.0 can be correlated within ±15% by the present prediction method. Also, the lower limit of film boiling was discussed in terms of wall heat flux and degree of superheating.

Quenching experiments on the transient film boiling heat transfer from a vertical cylinder to a quiescent saturated water at atmospheric pressure have been carried out for 18 kinds of silver cylinder which are 8 to 100mm in diameter and 8 to 160mm in length. The experimental data obtained by quenching method were compared in terms of boiling curve with the semi-empirical prediction method proposed by the authors. The experimental data agreed within ±15% with the prediction. The effect of aspect ratio (length-to-diameter ratio) on the lower limit of film boiling for saturated water was also discussed and its prediction method was proposed.

In order to clarify the effect of bottom and top configurations on pool film boiling heat transfer from a vertical cylinder with a length comparable to the diameter, five kinds of silver cylinder with flat, hemispherical and conical end surfaces were tested by quenching in saturated and subcooled water. For saturated water, the wall heat flux averaged over the total surface of a finite-length cylinder takes a higher value for the cylinder with a conical bottom than those for the other four types as the wall superheat decreases. For highly subcooled bulk water, the average wall heat flux for the cylinder with a flat bottom becomes larger than those for the cylinder with hemispherical and conical bottoms. This is attributed that the cylinder with a flat bottom has quite a thin vapor film at the lower end of the vertical finite-length cylinder due to the edge effect.

The solid temperature field of a vertical finite-length cylinder was numerically calculated with the convective boundary condition prescribed by a correlation equation proposed by authors for saturated film boiling heat transfer around a vertical finite-length cylinder. In order to examine the validity of the prediction, the experiments on the film boiling from a vertical test cylinder to a quiescent saturated water at atmospheric pressure have been carried out by a quenching method. The diameter and length of the test cylinder used in the experiment are, respectively, 45mm and 45mm and the cylinders are made of silver, copper, aluminum, carbon steel and stainless. The numerical values obtained by the finite difference method (explicit method) agreed well with the experimental data in terms of the cooling curve.

A two-dimensional lubrication equation of finite length journal bearings lubricated with ferrofluid considering both magnetic force and the effect of the angular momentum of particles in ferrofluid is developed. The numerical calculation results show that the latter, which was ignored by former researchers, is almost in the same order as the former and should not be neglected. The characteristics of the finite length journal bearing lubricated with ferrofluid involving the cavitation region of the bearing are investigated and discussed., rights: 社団法人日本機械学会rights: 本文データは学協会の許諾に基づきCiNiiから複製したものであるrelation: IsVersionOf: http://ci.nii.ac.jp/naid/110002383157/

We pewsent in this thsis the total energy calucations for the open edge growth mechanisms of carbon nanotubes by the density functional theory and the transferable tight binding model. The energetics of finite-length achiral nanotubes is discussd within the tight binding model at first. Comgining the strain energies ad the edge formation energies calculated by the tight binding model, we obtain the total energy of the finite-length nanotube as a, 2000, Includes bibliographical references

The theoretical analysis on the exhaust muffler of an engine contains various difficult factors. Consequently, almost all the recent reports are based on the presupposition that the tail pipe of a muffler has in finite length. In this paper, therefore, the theoretical formulas of attenuation are studied from the point of view that the tail pipe has finite length. The greater parts of the formulas shown in this paper are established by the application of the theories of electrical and mechanical engineering. As a supplement, a theoretical formula is induced in this paper to express what effect is obtainable when the inner walls of the muffler are made absorptive.

A travelling wave ultrasonic motor is an actuator that exploits vibration. Vibration in the ultrasonic range occurs in the stator, which is the oscillator of this motor. Because the vibration amplitude is extremely small, however, experimentation that employs the actual unit is difficult. In the research presented here, the stator of the ultrasonic motor was replaced by an elastic beam of finite length. A theoretical analysis of lateral vibrations of the beam, generated by imposing a forced displacement at the same frequency with a phase difference to both ends of this beam, was conducted. An apparatus was also fabricated with shakers installed on both ends of the beam. Appropriateness of the theoretical analysis was verified through experiments employing this apparatus. Consequently, generation of travelling waves, standing waves, and receding waves reliant upon the phase differences at the two ends became apparent through the theoretical analysis. The experimentation further confirmed undulations similar to the theoretical analysis results.

A travelling wave ultrasonic motor is an actuator that exploits vibration. Vibration in the ultrasonic range occurs in the stator, which is the oscillator of this motor. Because the vibration amplitude is extremely small, however, experimentation that employs the actual unit is difficult. In the research presented here, the stator of the ultrasonic motor was replaced by an elastic beam of finite length. A theoretical analysis of lateral vibrations of the beam, generated by imposing a forced displacement at the same frequency with a phase difference to both ends of this beam, was conducted. An apparatus was also fabricated with shakers installed on both ends of the beam. Appropriateness of the theoretical analysis was verified through experiments employing this apparatus. Consequently, generation of travelling waves, standing waves, and receding waves reliant upon the phase differences at the two ends became apparent through the theoretical analysis. The experimentation further confirmed undulations similar to the theoretical analysis results.

Eddy current testing (ECT) is one of the most representative nondestructive testing methods for metallic materials, parts, structures and so on. Operating principle of ECT is based on two major properties of the magnetic field. One is that alternating magnetic field induces eddy current in conducting materials. Thereby, an input impedance of the magnetic field source, i.e., electric source, depends on the eddy current path. Second is that the magnetic field distribution depends not only on the exciting but also on the reactive magnetic fields caused by the eddy currents in targets. Former and latter are the impedance sensing and magnetic flux sensing types, respectively.This paper concerns with an optimization of a new magnetic flux sensing type sensor named “∞ coil”. Exciting and sensing coils are composed of ∞ shape coil and a finite length solenoid coil wound on ferrite bar, respectively. Development of this ∞ coil fully depends on the 2D and 3D finite elements method modeling. According to the simulation results, we have worked out two types of ∞ coils. Practical experiments reflect the validity of both simulation and design aims, quite well. Thus, we have succeeded in developing ∞ coil having a higher sensibility compared with that of conventional one.

Eddy current testing (ECT) is one of the most representative nondestructive testing methods for metallic materials, parts, structures and so on. Operating principle of ECT is based on the two major properties of magnetic field. One is that alternating magnetic field induces eddy current in all of the conducting materials. Thereby, an input impedance of the magnetic field source, i.e., electric source, depends on the eddy current path. Second is that the magnetic field distribution depends only on the exciting but also the reactive magnetic fields caused by the eddy currents in targets. Former and latter are the impedance sensing and magnetic flux sensing types, respectively. This paper concerns with an optimization of a new magnetic flux sensing type sensor named "∞ coil" whose exciting and sensing coils are composed of the ∞ shape and finite length solenoid coil wound ferrite bar, respectively. Optimization of this ∞ coil fully depends on the 3D finite elements methods. According to the 3D finite element simulation results, we have successfully carried out the optimum size of two exciting coils and a sensing coil.

The wall superheat at the lower limit of film boiling of a vertical finite-length silver cylinder, ΔTmin, was determined experimentally by quenching method for saturated and subcooled water at atmospheric pressure. Five kinds of cylinders were tested where the end surface is flat, hemispherical or conical. The following results were obtained from the experiments. (a) For a cylinder with flat end surfaces, ΔTmin has an average value of 136 K for saturated water, irrespective of the aspect ratio, L/D, where L is the length and D the diameter of the test cylinder. ΔTmin increases linearly with an increase in liquid subcooling, ΔTsub, and exceeds always the thermodynamic limit of liquid superheat (about 225K) for water at atmospheric pressure for ΔTsub larger than 12K. This tendency is similar to the cases of a sphere and a horizontal cylinder obtained experimentally by Dhir and Purohit, and Nishio and U emura, respectively. (b)For five kinds of cylinders with various end configurations, ΔTmin is irrespective of the end configurations for saturated water. However, in subcooled water, Δ Tmin of the cylinder with flat end surfaces has a larger value than those with a hemispherical or conical end surface.

The film boiling heat transfer around a vertical finite-length aluminum cylinder with con-vex hemispherical bottom was investigated experimentally for quiescent water at atmospherericpressure. The experiments have been carried out by a transient method, i.e., quenching method.The diameter of test cylinder is 32mm and the total length is 48mm with 32mm length of verticallateral part. The test cylinder was heated to about 560°C in an electric furnace and then cooledin saturated and subcooled water with the immersion depth of about 100mm. The degree of liquidsubcooling was varied from 0 to 30K. The film boiling heat transfer increased in terms of heat fluxby 230% with an increase 30K in liquid subcooling at the wall superheating of 300K. The wallsuperheating and heat flux at the lower limit of film boiling increased with an increase in liquidsubcooling. Further, the experimental results for an aluminum cylinder were compared with thosefor a silver cylinder.

The film boiling heat transfer around vertical finite-length silver cylinders was investigatedexperimentally for quiescent water at atmosphereric pressure. The configurations of bottom andtop surfaces of silver cylinders are (1) flat bottom and flat top, (2) curved bottom and flat topand (3) flat bottom and curved top, where “flat” refers to “horizontal” and “curved” to “convexhemispherical”. The experiments have been carried out by a quenching method. The diameter ofthe test cylinder is 32mm and the lateral length is 32mm. The test cylinder was heated to about600°C in an electric furnace and then cooled in saturated and subcooled water with the immersiondepth of about 100mm. The temperature is measured using a K-type thermocouple inserted intothe center of the test cylinder. The degree of liquid subcooling was varied from 0 to 35K. The effectof bottom and top surfaces configurations on the degree of superheating and the wall heat flux atthe lower limit of film boiling was discussed., 長崎大学工学部研究報告, Vol.40(75), pp.1-7 ; 2010

The film boiling heat transfer around a vertical finite-length silver cylinder with convex hemispherical bottom and top surfaces was investigated experimentally for quiescent water at at-mosphereric pressure. The experiments have been carried out by a transient method, i.e., quenching method. The diameter of test cylinder is 32mm and the total length is 64mm with 32mm length of vertical lateral part. The test cylinder was heated to about 600°C in an electric furnace and then cooled in saturated and subcooled water with the immersion depth of about 100mm. The degree of liquid subcooling was varied from 0 to 35K. The film boiling heat transfer increased in terms of heat flux by 240% with 30K increase in liquid subcooling at the wall superheating of 300K. The wall superheating and heat flux at the lower limit of film boiling increased with an increase in liquid subcooling.

The film boiling heat transfer around a vertical finite-length silver cylinder with a convex hemispherical top was investigated experimentally for quiescent water at atmosphereric pressure.The experiments have been carried out by a transient method, i.e., quenching method. The diameter of test cylinder is 32mm and the total length is 48mm with 32mm length of vertical part. The test cylinder was heated to about 600°C in an electric furnace and then cooled in saturated and subcooled water with the immersion depth of about 100mm. The degree of liquid subcooling was varied from 0 to 30K. The film boiling heat transfer increased in terms of heat flux by 236% with an increase in 20K liquid subcooling at the wall superheating of 300K. The wall superheating and heat flux at the lower limit of film boiling increased with an increase in liquid subcooling., 長崎大学工学部研究報告 Vol.39(73), pp.1-7; 2009

Saturated film boiling heat transfer around a vertical finite-length cylinder with a convex hemispherical bottom was analyzed by taking into account each convective heat transfer on the bottom, side and top surfaces of an isothermal cylinder. The effects of length and diameter of the cylinder on the overall heat transfer rate was discussed in terms of boiling curve. The experimental data obtained by Yamada et al. are correlated well by the present analysis.

Saturated film boiling heat transfer around a vertical finite-length cylinder with a convex hemispherical bottom was analyzed by taking into account each convective heat transfer on the bottom, side and top surfaces of an isothermal cylinder. The effect of length and diameter of the cylinder on the overall heat transfer rate was discussed in terms of boiling curve. The present analysis agreed well with the experimental data obtained by the authors., 長崎大学工学部研究報告 Vol.37(69) p.8-15, 2007

Wave propagation in an infinite periodic railway track is investigated. In the analysis the constituents of a rail and sleepers are considered for the track model. Propagation modes of the periodic structure are described by virtue of the Floquet transform. This method makes it possible to reduce the infinite periodic problem to an eigenvalue problem for a unit structure with finite length. The rail is modeled by a Timoshenko beam and discretized by finite elements. Through numerical analysis the wave number-frequency curves for the propagation modes are obtained. It is found that the installation of sleepers causes a mode in which the propagation waves are accompanied by sleeper vibration. Besides, the influence of the stiffness of rubber pads on the propagation modes is discussed.

Correlating equations for the film boiling heat transfer from a vertical cylinder of finite-length to subcooled water were refined. The overall heat transfer rate around the cylinder was determined by taking into account each convective heat transfer on the bottom, side and top surfaces of the cylinder. The present prediction method was compared with the experimental data obtained by quenching method. The diameter and length of test cylinders used in the experiments are, 32mm x 16mm, 32mm x 32mm, 32mm x 64mm, 45mm x 45mm, 50mm x 16mm, 50mm x 32mm and 50mm x 64mm. The degree of liquid subcooling was varied from 2 to 30K. All the experimental data for the aspect ratio in 0.16 ≦ L/D ≦ 2.0 can be correlated within +-15% by the present prediction method.

Eddy current testing (ECT) is one of the most representative nondestructive testing methods for metallic materials, parts, structures and so on. Operating principle of ECT is based on the two major properties of magnetic field. One is that alternating magnetic field induces eddy current in all of the conducting materials. Thereby, an input impedance of the magnetic field source, i.e., electric source, depends on the eddy current path. Second is that the magnetic field distribution depends only on the exciting but also the reactive magnetic fields caused by the eddy currents in targets. Former and latter are the impedance sensing and magnetic flux sensing types, respectively.This paper concerns with a new magnetic flux sensing type sensor named "∞ coil" whose exciting and sensing coils are composed of the ∞ shape and finite length solenoid coil wound around a ferrite bar, respectively.Development of this ∞ coil fully depends on the finite elements method modeling. According to the simulation results, we have worked out two types of ∞ coils. Practical experiments reflect the validity of both simulation and design aims, quite well. Thus, we have succeeded in developing ∞ coil having a higher sensibility compared with that of conventional one.

Three-dimensional numerical computation was performed for the developing region of flow and thermal fields in finned channels. The channel studied here has a heated region of finite length to which plate fin arrays are attached in order to improve its heat transfer performance. The performance was evaluated using Nu_L^^*, an apparent Nusselt number corresponding to the heat transfer rate per unit heated area. The effect of fin height, fin pitch, fin length and Reynolds number on Nusselt number was examined parametrically. As the fin height increases with the fin pitch kept constant, Nu_L^^* increases monotonically. The maximum value of Nu_L^^* was obtained when the top of the fin reached the top wall of the channel. When the fin pitch was changed with the fin height kept constant, the numerical results demonstrated two tendencies. In the case with clearance between the fin top and the wall, there existed the optimal fin pitch leading to maximum Nu_L^^*. In the case without clearance, Nu_L^^* increases with decrease of fin pitch. The optimal fin pitch gradually decreased with decrease of fin length and/or with increase of Reynolds number. The ratio of the j-factor to the f-factor was also obtained to evaluate the performance of the fins.

In many manufacturing fields, i.e., space and airplane, automobile and electric engineering, the engineering use for laminated structures of different materials such as metals, plastics and composite materials becomes very common. If such a laminate is under any temperature change, the thermal stress is generated in it because the thermal properties such as thermal conductivity and a coefficient of thermal expansion of each component are generally quite different. This paper deals with the transient thermal stress analysis of laminates which are made of three components of finite length and manufactured at a certain constant temperature and then an upper and a lower components of the laminate are cooled and kept at 0℃ instantaneously, at the same time, side surfaces of the laminate are cooled by fluid of 0℃. The thermal stress and the temperature distribution at the interfaces between the components are examined from the numerical calculations in order to investigate the thermal strength of the laminate.

航空宇宙技術研究所 10-11 Jun. 1993 東京 日本, National Aerospace Laboratory 10-11 Jun. 1993 Tokyo Japan, 3次元ナビエ・ストークス方程式と2化学種保存方程式を解くことにより有限長さのスリットから直角に空気噴射を行う場合の超音速流れと混合の場を調べた。乱流モデルとして、ラージエディシミュレーションのサブグリッドスケールモデルを用いた。支配方程式の対流項にYeeタイプのTVD風上スキームを適用し、散逸項については中心差分を用いた。時間積分はLU分解陰解法を用いた。スリットの向きが90度と45度の2つの場合を扱った。3次元数値計算法の信頼性を確かめるため実験による測定を行った。ピトー圧力分布について数値計算結果を実測値と比較し、定性的および定量的にかなりよく一致する結果を得た。数値シミュレーションでは、混合場を調べるために主流と噴射された空気とは異なる化学種として取り扱った。90度スリットの場合、スリットが十分長いにも拘わらず、流れと混合場は端の存在のため3次元的となる。45度スリットの場合は3次元性がさらに強くなり、混合が促進される。いずれの場合も、スリットの下流側に到達する主流の部分はスリット端近傍の渦流よりも高い程度で混合の増進に影響する。, The supersonic flow and mixing fields with a perpendicular air injection from a finite length slit are investigated by solving the three dimensional full Navier-Stokes equations and the two chemical species conservative equations. As the turbulent model, the subgrid scale model of the large eddy simulation is employed. The Yee's type upwind total variation diminishing scheme is applied for the convective terms of the governing equations. The dissipation terms are evaluated by the central difference. The time integration is performed by using the Lower-Upper factored implicit method. Two slit angle cases of 90 deg and 45 deg are treated. The experimental measurements are performed in order to confirm the reliability of the three dimensional numerical code. The numerical results are compared with the experimental ones as regards the Pitot pressure distributions. The numerical results fairly agree with the experimental data both qualitatively and quantitatively. In the numerical simulation, the main flow air and the injected air arc treated as the different species, so the mixing fields can be examined. From the results in case of the 90 deg slit angle, even though the injection slit is long enough, the flow and mixing fields are rather three dimensional because of the existence of both side ends. All the results show that a part of the main flow which gets into downstream side of the slit influences on the mixing augmentation in the higher order than the vortex flow in the vicinity of the slit ends., 資料番号: AA0004171032, レポート番号: NAL SP-22

金沢大学高度モビリティ研究所 / 金沢大学理工研究域機械工学系, An entimation method for dynamic consitutive equations using the experimental data of strain time curves and the residual strain profile induced in a finite-length bar applied to longitudinal impact is described. The estimation was performed by means of the nonlinear least squares based on the Gauss-Newton method assuming the constitutive equation forms were given. The previous report explained that the method was applicable to estimation of dynamic consitutive equations for aluminium, stress-strain relations for which are weakly dependent on strain rates. In this study, in order to confirm that the present method could be applied to the estimation of dynamic consitutive equations of carbons steels, stress-strain relationships of which are highly depndent on strain rates, the estimations were performed using actual experimental data. Furthermore, by the comparison of estimated results and experimental results regarding stress-strain relationships with strain rates, it was clarified that the method might be applied to estimation of the dynamic constitutive equations of carbon steels.