In-flight deformation measurement for high-aspect-ratio wing based on 3D speckle correlation

In order to get an effective solution of the in-flight wing deformation measurement for high-wing aircrafts with high-aspect-ratio,a method based on three-dimensional(3D)speckle correlation technique is proposed.Firstly,an in-flight wing deformation measurement system with two sets of conjugate cameras is designed based on structural characteristics and test requirements of high-wing aircrafts with large-aspect-ratio.Secondly,the in-flight wing deformation measurement method based on 3D speckle correlation technique is introduced including three aspects:measuring system and wing datum calibration,speckle image matching and 3D reconstruction,and wing deformation analysis.Fi-nally,ground simulation test of dynamic deformation measurement of a scaled model wing and flight test of dynamic deformation measurement of a large transport wing are carried out.The test results show that the measuring accuracy of single point coordinate in ground simulation test is better than 0.1 mm/m,in the airborne vibration environment,the static single-point positioning accuracy is bet-ter than 5 mm,and the in-flight wing deformation measurement data is well received by the flight test engineers.This method can satisfy the requirements of stability,reliability,high precision,non-con-tact and full-field measurement for dynamic deformation measurement of aircraft wing with high-as-pect-ratio.

Development of high-aspect-ratio microchannel heat exchanger based on multi-tool milling process

A high-aspect-ratio microchannel heat exchanger based on multi-tool milling process was developed. Several slotting cutters were stacked together for simultaneously machining several high-aspect-ratio microchannels with manifold structures. On the basis of multi-tool milling process, the structural design of the manifold side height, microchannel length, width, number, and interval were analyzed. The heat transfer performances of high-aspect-ratio microchannel heat exchangers with two different manifolds were investigated by experiments, and the influencing factors were analyzed. The results indicate that the magnitude of heat transfer area per unit volume dominates the heat transfer performances of plate-type micro heat exchanger, while the velocity distribution between microchannels has little effects on the heat transfer performances.

Stiffness Distribution and Aeroelastic Performance Optimization of High-Aspect-Ratio Wings

The relationship between stiffness distribution and aeroelastic performance for a beam-frame model and a3-D model is investigated based on aeroelastic optimization of global stiffness design for high-aspect-ratio wings.The sensitivity information of wing spanwise stiffness distribution with respect to the twist angle at wing tip,the vertical displacement at wing tip,and the flutter speed are obtained using a sensitivity method for both models.Then the relationship between stiffness distribution and aeroelastic performance is summarized to guide the design procedure.By using the genetic/sensitivity-based hybrid algorithm,an optimal solution satisfying the strength,aeroelastic and manufacturing constraints is obtained.It is found that the summarized guidance is well consistent with the optimal solution,thus providing a valuable design advice with efficiency.The study also shows that the aeroelastic-optimization-based global stiffness design procedure can obtain the optimal solution under multiple constraints with high efficiency and precision,thereby having a strong application value in engineering.

Design and Simulation of BTT Missile with High-Aspect-Ratio Wing Robust H_∞ Autopilot

For the strong coupling among the channels of bank-to-turn （BTT） missile with high-aspect-ratio wing, an autopilot is designed with a two loop control structure robust autopilot design methods. By the inner loop design, the question of pole-zero cancellation is solved, and the stabilization of structured uncertainty is achieved. Through the outer loop of H∞ controller design, the flying performance and robustness can be guaranteed. The nonlinear simulation results show that the autopilot designed has perfect time domain response, and can suppress bad influence of the inertial and kinematics couplings. It can make the missile fly stably in the large flying areas. The control is very effective.

大展弦比复合材料前掠翼气动弹性分析与优化(英文)

In order to analyze the effects of forward-swept angle and skin ply-orientation on the static and dynamic aeroelastic characteristics, the aeroelastic modeling and calculation for high-aspect-ratio composite wings with different forward-swept angles and skin ply-orientation are performed. This paper presents the results of a design study aiming to optimize wings with typical forward-swept angles and skin ply-orientation in an aeroelastic way by using the genetic/sensitivity-based hybrid algorithm. Under the conditions of satiated multiple constraints including strength, displacements, divergence speeds and flutter speeds, the studies are carried out in a bid to minimize the structural weight of a wing with the lay-up thicknesses of wing components as design variabies. In addition, the effects of the power of spanwise variation function of lay-up thicknesses of skins and iugs on the optimized weights are also analyzed.

大展弦比复合材料机翼结构建模与气动弹性分析(英文)

A unified structural model for high-aspect-ratio composite wing with arbitrary cross-section is developed. Two types of lay-ups of the composite wing, namely, circumferentially uniform stiffness （CUS） configuration and circumferentially asymmetric stiffness （CAS） configuration, are investigated. The present structural modeling method is validated through ANSYS FEM software for the case of a composite box beam. Then, the case of a single-cell composite wing with NACA0012 airfoil shape is considered. To investigate the aeroelastic problem of high-aspect-ratio composite wings, the linear ONERA aerodynamic model is used to model the unsteady aerodynamic loads under the case of small angle of attack. Finally, flutter speeds of the high-aspect-ratio wing with various composite ply angles are determined by using U-g method.

大展弦比复合材料机翼失速颤振分析(英文)

The stall flutter characters of high-aspect-ratio composite wing are investigated, and the effects of structure geometric nonlinearity and stiffness couple created by composite anisotropy on them also are discussed. Firstly, the high-aspect-ratio wing is modeled as a composite thin-walled closed section Euler beam whose displacement and rotation both could be of finite value, and the nonlinear dynamic equations is build up on it with all the effects of geometric nonlinearity, aerodynamic nonlinearity and anisotropy of material being considered. Then vibration equations are deduced through perturbing the dynamic equations at wing＇s equilibrium position, and coupled with unsteady stall aerodynamic model and ONERA model, to obtain the nonlinear stall flutter analysis equations of wing. Finally, the flutter stabilities with various wind speeds are determined by the harmonic balance method. With several exampies, the validity of the stall flutter model is proved, and the significant effects of geometric nonlinearity on the stall flutter various characters as wall as the effects of ply angle on the stall flutter speed and frequency also are discussed.

Diagnosis and Treatment of Lacrimal Passage Obstruction by Lacrimal Endoscope

The diagnosis and treatment of the lacrimal passage obstruction with lacrimal endoscope was investigated and its subsidiary surgical procedures were evaluated. Ninety-three patients （109 eyes） with lacrimal passage obstruction, including presaccal canalicular obstruction （PSCO） and nasolacrimal duct obstruction （NLDO）, were examined under a lacrimal endoscope, and the obstruc- tions were treated with laser or micro-drill. All patients were followed up after the operation for 3--6 months. The difference between the laser and the micro-drill treatment was observed. During the period of follow-up, the curative rate was 82.57%. The healing rate in PSCO group and NLDO was 80.36% and 84.91% respectively （P〉0.05）. Alter treatment with the laser, the healing rate was 93.33% in the PSCO group and 66.67% in the NLDO group respectively （P〈0.05）. After treatment with the micro-drill, the healing rate in PSCO and NLDO groups was 65.39% and 94.28% respec- tively （P〈0.01）. The lacrimal passage obstruction can be observed and treated directly through the lacrimal endoscope. Choosing different surgical procedures in operation according to the locations of the obstruction is helpful to improve the effectiveness.

Large-scale Patterning of Hydrophobic Silicon Nanostructure Arrays Fabricated by Dual Lithography and Deep Reactive Ion Etching

We describe a simple but efficient technique to fabricate large-scale arrays of highly ordered silicon nanostructures. By coupling dual lithography using light of 351.1 nm wavelength with deep reactive ion etching(DRIE), silicon nanostructures of excellent regularity and uniform coverage were achieved. The proposed nanofabrication method not only simplified the nanofabrication process but also produced highaspect-ratio(higher than 15) nanostructures. The scalloping problem was also controlled by regulating DRIE parameters. The process is rapid, cheap, examined to optimize the fabrication process, and has the potential to be scaled up to large areas. The contact angle of a water droplet atop the surface is larger than 150?.Moreover, by coupling black silicon process with DRIE-based microfabrication, three-dimensional nano/nano dual-scale structures which show robust and stable hydrophobicity have been achieved. This process opens new application possibilities in optical, photoelectric, microelectronic, catalytic and biomedical applications.

高厚径比微型钻头开发

随着印制板技术的发展,高厚径比孔的需求越来越大,常规槽长的微钻无法用于该类印制板的钻孔,亟需开发高性能的特殊槽长微钻,为高厚径比孔的加工提供解决方案。论文首先给出了高厚径比微钻的开发背景以及高厚径比微钻开发的关键问题。然后阐述了高厚径比条件下如何优化微钻设计来保障包括微钻的抗断钻、孔位精度和孔壁粗糙度在内的综合性能。最后给出了直径0.3mm、槽长直径比为24的微型钻头开发实例,并且通过试验进行了验证,结合钻孔试验介绍了高厚径比孔钻削的关键技术。

高厚径比微型孔对接钻加工方法探究

伴随电子行业技术的日益发展，与之相对应印制电子线路板（PCB）的设计与制造也有了明显变化：为满足电子线路高密度的需求，PCB上微钻孔的孔径日趋降低：小孔径、高厚径比板件的机械孔加工技术，已成为PCB制造，尤其是背板加工过程中越来越重要的技术难点，成为制约板件电性能、降低加工成本的关键技术控制点。正反对接钻孔，由于其自身优势，现已成为行业内主要高厚径比板件钻孔的加工方法。本文通过一系列试验，探究了对接钻孔过程中，主轴钻速、进刀速、钻头刃长对孔壁质量和对接处台阶尺寸的影响，并对此做出一系列分析；通过调整参数及分步方法，制备出孔壁状态良好的高厚径比的微型孔。

一种干法刻蚀形成高深宽比CIS Deep-P Well IMP掩模的工艺方法的探究

为有效提升CIS(CMOS Image Sensor)器件的FWC(Full Well Capacity),需要将更高能量的DWP IMP注入到更小的space pattern区,相比较单一的光刻胶,引入TRL(TriLayer:PR/Si HM/SOC)并使用干刻方法能有效地形成了high-aspect-ratio(高深宽比,>20)的图案掩模。其中,DPW IMP阻挡掩模可以做到更厚,约4.2μm,DPW pattern的space可以做到更小,约0.2μm。该工艺革新为后续deeper DPW IMP,pixel shrinking,同时提升CIS器件的FWC光素性能提供了可能,针对引入TRL的干刻工艺的主要建立过程予以技术说明。

横刃修磨高长径比微细钻削刀具的钻削性能研究

横刃修磨方法是一种提高钻削刀具加工性能的有效手段。针对横刃修磨高长径比微钻,建立了刀具螺旋槽、非共轴螺旋后刀面和十字型横刃的数学模型,并基于六轴数控工具磨床刃磨制备出直径0.5 mm、长径比为10的横刃修磨高长径比非共轴螺旋后刀面微钻。在304不锈钢材料上开展了普通高长径比微钻和横刃修磨高长径比微钻的对比钻削试验研究,从钻削力、刀具磨损、微小深孔加工质量等方面分析了横刃修磨对高长径比微细钻削刀具钻削性能的影响。结果表明,与普通高长径比微钻相比,横刃修磨高长径比微钻的钻削轴向力和钻尖磨损程度明显降低,在钻削5个微小深孔后,横刃修磨高长径比微钻的后刀面和横刃的最大磨损宽度分别减小了26%和32%;横刃修磨高长径比微钻所加工的微小深孔具有更规则的入口形状、更低的圆度误差和孔壁粗糙度。研究证实了横刃修磨方法能够显著提高高长径比微钻的钻削性能。

超大长径比极细硬质合金微型钻头结构及涂层技术研究

针对超大长径比极细微型钻头工作中的微弯曲变形情况进行了分析。通过软件计算,得到微型钻头未钻入板材时不同旋转速度对微型钻头偏摆距离的影响。随后模拟微型钻头钻入板材后的受力情况,计算了微型钻头在槽长区域有、无约束条件下的变形量,研究了微型钻头槽长区域不同约束位置、约束方式对微弯曲变形的影响。研制了新型自对正结构的超大长径比极细微型钻头,并应用于加工8 mm大厚度高速通信印制电路板。利用两端对向钻削的方法对其进行通孔加工,研究了微型钻头的结构和涂层对孔偏距的影响。结果表明,钻入板材前,随着转速从150 kr/min增加到245 kr/min,钻尖偏摆距离从0.02 mm增加到0.6 mm;钻入板材后,在槽长区域设计约束结构可有效降低微弯变形量;通过超润滑涂层解决了极细微型钻头的断刀问题、减小了孔偏距。相比于常规结构的微型钻头,新型微型钻头涂层后可将孔偏距从56μm降低到35μm,满足使用要求。

Studies on the influence of spar position on aeroelastic optimization of a large aircraft wing

Aeroelastic problems are encountered at the preliminary design stage of flexible wings for large aircraft.A three-dimensional finite element model of a high-aspect-ratio wing was built,and the influence of the front and rear spar positions on the results of the aeroelastic analysis and optimization was studied to improve the wing structure desgin.The most feasible and optimal solutions were effectively obtained by aeroelastic optimization.In particular,the position parameter of the front spar has a greater influence on the aeroelastic analysis and optimization than the rear spar.In addition,some key constraints became re-strictive leading to a rapid increase in the structural weight.Therefore,reasonable constraints were necessary for the oprimiza-tion of results.