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Chinese Journal of Aeronautics 2013年第1期26卷 242-248页

作者： Tian Shan Liu Yuli Yang He State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Inner flange and side wrinkling often occur in rotary-draw bending process of rectangular aluminum alloy wave-guide tubes, and the distribution and magnitude of wrinkling is related to geometrical parameters of the tubes. In order to study the effects of geometrical parameters on wrinkling of rectangular wave-guide tubes, a 3D-FE model for rotary-draw bending processes of thin-walled rectangular aluminum alloy wave-guide tubes was built based on the platform of ABA-QUS/Explicit, and its reliability was validated by experiments. Simulation and analysis of the influence laws of geometrical parameters on the wave heights of inner flange and side wrinkling were then carried out. The results show that inner flange wrinkling is the main wrinkling way to rectan- gular wave-guide tubes in rotary-draw bending processes, but side wrinkling cannot be neglected because side wrinkling is 2/3 of inner flange wrinkling when b and h are smaller. Inner flange and side wrinkling increase with increasing b and h; the influence of b on side wrinkling is larger than that of h, while both b and h affect inner flange wrinkling greatly. Inner flange and side wrinkling decrease with increasing R/h; the influence of h on inner flange and side wrinkling is larger than that of R.

关键词： geometrical parameters Inner flange wrinkling Side wrinkling Simulation Thin-walled rectangular wave-guide tube Rotary-draw bending

Effect of geometrical parameters on forming quality of high-strength TA18 titanium alloy tube in numerical control bending

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Transactions of Nonferrous Metals Society of China 2018年第2期28卷 309-318页

作者：方军梁闯鲁世强王克鲁江西科技师范大学江西省材料表面工程重点实验室南昌330038 南昌航空大学轻合金加工科学与技术国防重点学科实验室南昌330063

The forming quality of high-strength TA18 titanium alloy tube during numerical control bending in changing bending angle β, relative bending radius R/D and tube sizes such as diameter D and wall thickness t was clarified by finite element simulation. The results show that the distribution of wall thickness change ratio Δt and cross section deformation ratio ΔD are very similar under different β; the Δt and ΔD decrease with the increase of R/D, and to obtain the qualified bent tube, the R/D must be greater than 2.0; the wall thinning ratio Δto slightly increases with larger D and t, while the wall thickening ratio Δti and ΔD increase with the larger D and smaller t; the Δto and ΔD firstly decrease and then increase, while the Δti increases, for the same D/t with the increase of D and t.

关键词： high-strength TA18 tube geometrical parameters forming quality finite element simulation numerical control bending

Analysis of the Hydraulic Performances of a New Liquid Emitter Based on a Leaf Vein Concept

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Fluid Dynamics & Materials Processing 2023年第8期19卷 2147-2160页

作者： Tianyu Xu Zhouming Su Yanru Su Zonglei Li Quanjie Chen Shuteng Zhi Ennan Zheng Kaili Meng School of Hydraulic and Electric Power Heilongjiang UniversityHarbin150080China

The leaf-vein drip irrigation emitter is a new type of drip emitter based on a bionic structure able to support shunting,sharp turns,and increased *** the present work,the results of twenty-five tests executed in the framework of an orthogonal design strategy are presented in order to clarify the influence of the geometrical parameters of the flow channel on the hydraulic characteristics of such *** corresponding flow index and head loss coefficient are determined through numerical simulations and model *** results show that the flow index of the flow channel is 0.4970∼0.5461,which corresponds to good hydraulic *** head loss coefficient of the flow channel is 572.74∼3933.05,which in turn indicates a good energy dissipation *** order of influence of the leaf vein flow channel parameters on the flow index can be represented in a synthetic way as a>b>c>d>e,where(a)is the width of the inlet,(b)is the horizontal distance of the front water inlet,(c)is the vertical distance of the inner edge of the front end,(d)is the horizontal distance of the rear water outlet and(e)is the vertical distance of the outer edge of the front *** flow index increases with d,decreases with a,first decreases,and then increases with b,and first increases and then decreases with the increase of c and *** coefficient(R^(2))of the fitted model related to geometric parameters and flow index is *** relative errors among experimental testing,simulation calculation and predictive estimates are shown to be less than 5%.

关键词： Leaf vein flow channel geometrical parameters flow index energy dissipation

A parametric study on unbalanced moment of piston type valve core

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第4期22卷 265-276页

作者： Jin-yuan QIAN Juan MU Cong-wei HOU Zhi-jiang JIN Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

In this paper,the piston type valve core and the unbalanced moment on its bottom are *** decrease the influence of non-common geometrical factors,a simplified model of the piston type globe valve is proposed in this *** on the computational fluid dynamics(CFD)method,the effects of different geometrical parameters on the unbalanced moment existing on the bottom of the valve core,which include the bending radius of the inlet flow channel,the diameter of the special-shaped pipe,and the height of the valve core,are ***,the effects of geometrical parameters on the unbalanced moment on the bottom of the valve core are clarified by correction and variation classification and provide a basis for further optimizing the structure of the piston type *** results show that the unbalanced moment decreases with the increase of the bending radius of the inlet flow channel,but increases with the increase of the diameter of the special-shaped pipe and the height of the valve ***,the relation between the unbalanced moment and flow rate is proposed.

关键词： Piston type valve core Unbalanced moment geometrical parameters Computational fluid dynamics(CFD)

A NEW GENERATING METHOD FOR THE MACHINING OF A CYLINDRICAL GEAR WITH SYMMETRIC ARCUATE TOOTH TRACE

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Journal of Pharmaceutical Analysis 2004年第1期16卷 18-21,34页

作者：马振群龚堰珏王小椿 School of Mechanical Engineering

Objective To introduce a new generating method for the machining of a cylindrical gear with symmetric arcuate tooth trace. Methods Adopting this method, the key problems of mismatch control and manufacturing of symmetric arcuate tooth trace gears are solved by using suitable cutter tilt and a new generating method with double-edge gear-wheel cutter. The machining principle is analyzed and the mathematical model of generating motion is established. Then the tooth flank equation and differential geometrical parameters are discussed. Results The minim alteration of cutter tilt will make the contact flank area change so as to satisfy the special requirements. It is easy to realize the tip relief of gearing by altering coefficients of every moving axis. Because the tooth has the arc shape, the symmetrical arcuate cylindrical gears have higher overall strength and it is easy to perform the flank grinding for high precision. Conclusion This new generating method has higher productivity. It is easy to get a perfect contact zone and fully give play to the potential bearing capacity of the gears. The symmetrical arcuate cylindrical gears can be used in highly durable and heavy duty gearing applications.

关键词： symmetric arcuate tooth trace cylindrical gear generation geometrical parameters

Activation Energy of Modified Peak Shape Equations

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World Journal of Nuclear Science and Technology 2017年第4期7卷 274-283页

作者： Hugo ABorbón-Nunez Claudio Furetta CONACYT-Centro de Nanociencias y Nanotecnología UNAMEnsenada B.C.Mexico Retired from Physics Department of Rome University RomeItaly

The aim of this paper is to give some simplified expressions related to the peak shape method. The modified equations have been used to calculate the activation energy (E) of commercial thermoluminescent dosimeters (TLD), as well as of ZnO thermoluminescent material produced in laboratory;the values so determined have been compared to the values obtained using the classical expressions of the peak shape method. The modified equations proposed are as a function of peak shape parameters or the peak temperature at the maximum. This expression could be useful to obtain approximated E values in the case of complex glow curves as well, when the peaks are not well resolved but the peak temperature at the maximum may be easily determined.

关键词： Thermoluminescence geometrical parameters Activation Energy Peak-Shape Method

Application of Standardization for Initial Design of Plastic Injection Moulds

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厦门大学学报（自然科学版） 2002年第S1期41卷 202-页

作者： Low Maria Leng-Hwa LEE Kim-Seng Department of Mechanical Engineering Manufacturing Division National University of SingaporeDepartment of Mechanical Engineering Manufacturing Division National University of Singapore SingaporeSingapore

Today, the time-to-market for plastic products ar e getting shorter, thus the lead-time for making the injection mould is decreasin g. There is potential in timesavings in the mould design stage because the design process that is repeatable for every mould design can be standardized. T he preliminary work of any final plastic injection mould design is to always pro vide an initial design of the mould assembly for product designers (customers) p rior to receiving the final product CAD data. Traditionally and even up till no w, this initial design is always created using 2D CAD packages. The information used for the initial design is based on the technical discussion checklist, in which most mould makers have their own standards. This checklist is also being used as a quotation since the most basic information of the mould in the particu lar project is being recorded in it. The basic information in this checklist in cludes the number of cavities, the type of mould base to be used, the moulding m achine to be used for the moulding, the type of gating system, the type of resin material used and its shrinkage value etc. Information on special requirements such as the number of sliders or lifters to be used is also listed in the check list. At this stage, there is still no information on the cooling and ejection design since they are greatly dependent on the final product CAD data. This res earch focuses on the methodology of providing the initial design in 3D solid bas ed on the technical discussion checklist, which takes the role of the overall st andard template since every sub-design has its own standard template. An examp le of a sub-design that has its own standard template is the cavity layout desi gn. The cavity layout for plastic injection moulds can be designed by controlli ng the geometrical parameters using a standardization template. The standardiza tion template for the cavity layout design consists of configurations for the po ssible layouts. Each configura

关键词： standardization template plastic injection mould design initial design technical discussion checklist geometrical parameters