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A modal theory and recursion RTCM algorithm for gratings of deep grooves and arbitrary profile

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Science China Mathematics 1999年第6期42卷 636-645页

作者：傅克祥王植恒张大跃张靖张奇志 Department of Physics Sichuan University Chengdu China

A modal theory for gratings of deep grooves and arbitrary shape is developed. The theory is implemented with an algorithm of recursion reflection-transmission coefficient matrix (RTCM). Several cases of plane wave with arbitrary polarization and arbitrary angle of incidence diffracted from gratings of deep grooves and arbitrary profile are calculated. It is found that this method is more accurate, more stable and faster than others.

关键词： deep grooves RTCM arbitrary profile diffraction gratings.

Vacuum Infusion Molding Process (Part 2 VIMP Based on grooves)

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Journal of Wuhan University of Technology(Materials Science) 2003年第4期18卷 68-71页

作者：祝颖丹 Wuhan University of Technology

The optimal parameters for flow grooves and supply grooves were determined by a series of experiments,and the influences of various molding conditions on the mold filling process were analyzed.Furthermore,the whole VI... 详细信息

关键词： vacuum infusion molding process grooves mold filling

Effects of groove-textured surfaces filled with Sn-Ag-Cu and MXene-Ti_(3)C_(2) composite lubricants on tribological properties of CSS-42L bearing steel

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Friction 2022年第7期10卷 1091-1113页

作者： Yawen XUE Chaohua WU Xiaoliang SHI Qipeng HUANG Ahmed Mohamed Mahmoud IBRAHIM School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan 430070China Shenzhen Research Institute of Wuhan University of Technology Shenzhen 518000China Department of Production Engineering and Mechanical Design Faculty of EngineeringMinia UniversityEI-Minya 61519Egypt

To improve the tribological performance of CSS-42L bearing steel,smooth surfaces(SSs),groovetextured surfaces(GSs),GSs with Sn-Ag-Cu(GSs-SAC),and GSs with Sn-Ag-Cu-Ti_(3)C_(2)(GSs-SACT)were prepared on CSS-42L.In addition,experimental studies were conducted on tribological properties.The obtained results indicated that GSs-SACT exhibited the best anti-friction and noise reduction performances.These remarkable tribological performances were attributed to the synergistic effects of grooves,Sn-Ag-Cu,and MXene-Ti_(3)C_(2).The inconsistent rules of frictional forces were improved by the grooves and SACT,which inhibit the friction-induced noise.The micro-nano size-effects of MXene-Ti_(3)C_(2) enhanced the repairing effect and anti-friction property of composite lubricants,which improved the profile characteristics of GSs-SACT.

关键词： CSS-42L MXene Sn-Ag-Cu-Ti_(3)C_(2)(SACT) grooves tribological properties friction-induced noise

Numerical and experimental investigation on aluminum 6061-Vgrooved stainless steel 304 explosive cladding

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Defence Technology（防务技术） 2022年第2期18卷 249-260页

作者： C.Wilson dhileep kumar S.Saravanan K.Raghukandan Department of Mechanical Engineering Annamalai UniversityAnnamalainagarTamilnadu608002India Department of Manufacturing Engineering Annamalai UniversityIndia

This study attempts to analyze the microstructure and interface behavior of aluminum 6061(Al 6061)-Vgrooved stainless steel(SS304)explosive cladding by numerical and experimental methods.Numerical simulation was performed by Smoothed Particle Hydrodynamics(SPH)technique,in ANSYS AUTODYN,and the results are correlated with experimental outcome.The machining of V-grooves on the base plate transform the melted layer formed in conventional cladding(without grooves on the base plate)into a smooth undulating interface,for a similar experimental condition.The flyer plate and collision velocities,observed in numerical simulation,are in good agreement to the analytical expectations.The pressure developed in the flyer plate is higher than the base plate and the maximum pressure is witnessed at the collision point irrespective of grooved base plate or otherwise.The temperature developed in the collision point of conventional explosive cladding exceeds the melting point of both the participant metals,whereas,it exceeds the melting point of aluminum alone,in case of V-grooved base plate cladding.The shear and impact strengths of the V-grooved base plate clads are higher than the conventional clads and the fracture surfaces exhibit mixed modes of fracture.

关键词： Explosive cladding Dissimilar metals grooves Numerical simulation Interface Strength

A Spectral Finite Difference Method for Analysis of a Fluid-Lubricated Herringbone grooves Journal Bearing under a Special Case at Rectangle Groove

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Applied Mathematics 2019年第12期10卷 1029-1038页

作者： Jun Liu Tochigi R&D Center Keihin-Corp.Tochigi Japan

A spectral difference method is applied to get numerical solutions for a fluid-lubricated herringbone grooved journal bearing with trapezoidal grooves by previous work of the authors. However, an inexpedience in which Fourier series of the film profile does not converge at jump points of groove start or groove end in the case of rectangle groove was still remained. In the paper, an inexpedience of numerical analysis under a special case at rectangle groove is challenged to solve. As a result, for compensation of which Fourier series does not converge at jump points in a special case of rectangle groove, Fourier coefficient of fluid film thickness is proposed as taking the limit of which in a case trapezoidal groove at trapezoidal angle approaches 0.

关键词： Fluid-Lubricated Herringbone grooves Journal Bearing Spectral Difference Scheme Fourier Series Gibbs Phenomenon

Strength of Thin-Walled Lipped Channel Section Columns with Shell-Shaped Curved grooves

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Open Journal of Civil Engineering 2018年第4期8卷 508-523页

作者： Koki Hoshide Mitao Ohga Pang-jo Chun Tsunemi Shigematsu Sinichi Kawamura Department of Civil & Environmental Engineering Ehime University Matsuyama Japan Department of Technology Tokuyama College Tokuyama Japan Department of Kure College of Technology Kure Japan

Thin-walled member is structurally superior to a construction member. However, by reason of complexity in structure the stress and the deformation to yield the cross section are complicated. Specially, in case thin-walled members, such as thin-walled channel section columns, which are subjected to compressive force, these members produce the local buckling, distortional buckling and overall buckling. A number of experimental and theoretical investigations subjected to axial compressive force are generated for thin-walled channel section columns with triangle-shaped folded groove by Hancock [1] and with complex edge stiffeners and web stiffeners by Wang [2]. In case thin-walled channel section column with folded groove which is subjected to axial compressive force, it is cleared that the buckling mode shapes are ordinarily generated for local buckling mode shape of plate-panel composing cross section of member in short member aspect ratio and overall buckling mode shape as column and distortional buckling mode shape interacting between local buckling and overall buckling similarly normal thin-walled member. It is cleared analytically and experimentally that buckling strength and critical strength of thin-walled channel section column with folded groove can increase sharply in comparison with that of normal thin-walled member composing only plate-panel. In this paper a new cross section of shell-shaped curved groove [3] was proposed instead of the thin-walled lipped channel section column with triangle- and rectangle-shaped folded grooves used ordinarily, and therefore the comparison and the examination of buckling strength and buckling behavior were generated in the case of preparing triangle-shaped folded and shell-shaped curved grooves to web and flange of thin-walled channel section column. And then in order to investigate the buckling behavior on the thin-walled channel section column with folded and curved grooves, exact buckling strength and the buckling mode shapes are generated by using the transfer matrix

关键词： Transfer Matrix Method Folded and Curved grooves Local Distortional and Overall Buckling Strength Buckling Mode Shapes

A Numerical Study on Pressure Drop in Microchannel Flow with Different Bionic Micro-Grooved Surfaces

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Journal of Bionic Engineering 2012年第1期9卷 99-109页

作者： Jing Cui Yabo Fu School of Airport Civil Aviation University of China Tianjin 30300 P. R. China College of Physics and electronic engineering Taizhou University Taizhou 318000 P. R. China

The studies of bionics reveal that some aquatic animals and winged insects have developed an unsmoothed surface possessing good characteristics of drag reduction. In this paper, four types of bionic surfaces, placoid-shaped, V-shaped, rib- let-shaped, and ridge-shaped grooved surfaces, are employed as the microchannel surfaces for the purpose of reducing pressure loss. Lattice Boltzmann Method （LBM）, a new numerical approach on mescoscopic level, is used to conduct the numerical investigationsr. The results show that the micro-grooved surfaces possess the drag reduction performance. The existence of the vortices formed within the grooves not only decrease the shear force between fluid and wall but also minimize the contact area between fluid and walls, which can lead to a reduction of pressure loss. The drag reduction coefficient （η） for these four types of micro-structures could be generalized as follows： ηridge_shaped 〉 ηv-shaped 〉 ηplacoid-shaped 〉 ηriblet-shaped. Besides, the geometrical optimizations for the ridge-shaped grooves, which have the highest drag reduction performance, are performed as well. The results suggest that, for the purpose of drag reduction, the ridge-shaped grooves with smaller width to height ratio are recommended for the lower Reynolds number flow, while the ridge-shaped grooves with larger width to height ratio are be more suitable for the larger Reynolds number flow.

关键词： microchannel bionic grooves drag reduction lattice Boltzmann method

Nanoscale spatial phase modulation of GaAs growth in V-grooved trenches on Si(001) substrate

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Chinese Physics B 2016年第12期25卷 451-454页

作者：李士颜周旭亮孔祥挺李梦珂米俊萍王梦琦潘教青 Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of Sciences

This letter reports the nanoscale spatial phase modulation of GaAs growth in V-grooved trenches fabricated on a Si （001） substrate by metal-organic vapor-phase epitaxy, Two hexagonal GaAs regions with high density of stacking faults parallel to Si {111 } surfaces are observed. A strain-relieved and defect-free cubic phase GaAs was achieved above these highly defective regions. High-resolution transmission electron microscopy and fast Fourier transforms analysis were performed to characterize these regions of GaAs/Si interface. We also discussed the strain relaxation mechanism and phase structure modulation of GaAs selectively grown on this artificially manipulated surface.

关键词： phase modulation GaAs grooves Si

Numerical simulation of droplet-formation in rotary atomizer

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Theoretical & Applied Mechanics Letters 2019年第3期9卷 202-205页

作者： Naoki Igari Takuro Iso Yu Nishio Seiichiro Izawa Yu Fukunishi Tohoku University

Numerical simulations of the liquid flow scattering from rotary atomizers are performed using an incompressible smoothed particle hydrodynamics (SPH) method. The influence of grooves at the edges of the atomizers on the formation of ligaments and droplets is investigated changing the numbers and shapes of the grooves. As a result, it is found that small droplets are likely to be generated when the number of grooves is large and the depth of grooves is deep. It is also found that the grooves work more effectively in bell-cup atomizers than in disk type atomizers.

关键词： Smoothed particle hydrodynamics (SPH) Rotary atomizer grooves Droplet