發(fā)布時間：2018-05-03 11:00

  本文選題：復(fù)合材料 + 縮比模型��； 參考：《大連理工大學(xué)》2015年碩士論文

【摘要】：在現(xiàn)代飛機設(shè)計工作中,針對飛機縮比物理模型的風(fēng)洞試驗是一項獲得飛機氣動彈性特征的重要工作。風(fēng)洞試驗中的縮比物理模型是試驗的對象,其幾何外形特征,氣動彈性特征都需要與飛機設(shè)計方案保持高度的相似性,從而準確反映飛機設(shè)計方案的特點。近些年來,由多相材料復(fù)合而成的復(fù)合材料,綜合發(fā)揮了其各組成材料的優(yōu)點,呈現(xiàn)出了比單一材料更具優(yōu)勢的性能,在航空航天等方面,得到了大量的應(yīng)用。由于復(fù)合材料優(yōu)異的力學(xué)性能可設(shè)計性,以復(fù)合材料結(jié)構(gòu)為主體的機翼結(jié)構(gòu)相似縮比模型也成為了現(xiàn)代飛機風(fēng)洞試驗研究的熱點。本論文研究的樹脂基復(fù)合材料,均使用熱固性樹脂作為材料基體,使用模塑成型工藝制造成型。其中,熱固性樹脂的固化是一個復(fù)雜的熱學(xué)、化學(xué)和力學(xué)過程,在固化過程中材料力學(xué)性能及熱物理性能發(fā)生急劇變化,而且由于樹脂基體和增強纖維的熱膨脹系數(shù)存在較大的差距,兼之樹脂在固化工程中發(fā)生了化學(xué)收縮,以及模具與復(fù)合材料之間的剪切作用等,使得復(fù)合材料結(jié)構(gòu)件內(nèi)部在固化過程中有較大的固化應(yīng)力,但是由于受到模具型腔的約束,使得復(fù)合材料結(jié)構(gòu)內(nèi)部的固化應(yīng)力無法得到釋放,因此在復(fù)合材料固化成型完成,脫離模具型腔之后,復(fù)合材料結(jié)構(gòu)內(nèi)部的固化應(yīng)力會得到釋放,一段時間過后,復(fù)合材料結(jié)構(gòu)會出現(xiàn)變形的現(xiàn)象,影響了復(fù)合材料結(jié)構(gòu)的外形精度以及相關(guān)力學(xué)性能。機翼復(fù)合材料結(jié)構(gòu)相似縮比模型在固化后會產(chǎn)生變形等現(xiàn)象,影響外形精度,進一步影響模型的氣動特性及風(fēng)洞試驗數(shù)據(jù)的可靠性。本論文首先用應(yīng)變片測定了環(huán)氧樹脂、單向復(fù)合材料、玻璃纖維正交復(fù)合材料與碳纖維正交復(fù)合材料等基本材料的固化殘余應(yīng)力及變形情況,求得了等效熱膨脹系數(shù),并且做了相應(yīng)的拉伸試驗,得到了需要的力學(xué)性能參數(shù)。通過建立的研究樹脂基復(fù)合材料殘余應(yīng)力的理論模型,結(jié)合已經(jīng)得到的相關(guān)參數(shù),用理論分析的方法和大型三維軟件ANSYS仿真的方法對上述層合板的固化變形進行了分析驗證�？紤]到傳統(tǒng)的試驗方法研究風(fēng)洞試驗縮比模型的固化變形將浪費很多的時間和材料,成本增加,因此采用有限元分析方法對固化變形進行分析和預(yù)測來代替反復(fù)試驗。在論文的最后用ANSYS軟件建立了有限元模型,對機翼復(fù)合材料結(jié)構(gòu)相似縮比模型進行了固化變形預(yù)測,為后續(xù)改進工藝奠定了基礎(chǔ)。
[Abstract]:In the design of modern aircraft, wind tunnel test for the physical model of aircraft shrinkage is an important work to obtain the Aeroelastic characteristics of aircraft. The shrinkage physical model in wind tunnel test is the object of the test. The geometric shape and Aeroelastic characteristics of the model need to keep the height similarity with the aircraft design plan so as to accurately reflect the characteristics of the aircraft design scheme. In recent years, composite materials composed of multiphase materials have brought into full play the advantages of each component material, and have shown more advantages than single materials, and have been widely used in aerospace and other fields. Because of the excellent design of mechanical properties of composite materials, the similar shrinkage model of wing structures with composite structures as the main body has become a hot spot in modern aircraft wind tunnel tests. In this paper, thermosetting resin is used as matrix and molding process is used. The curing of thermosetting resin is a complicated thermal, chemical and mechanical process. Moreover, the thermal expansion coefficient of resin matrix and reinforced fiber has a big gap, and the resin has chemical shrinkage in curing engineering, as well as the shearing effect between mould and composite material, etc. The internal solidification stress of the composite structure is larger in the curing process, but due to the constraints of the mold cavity, the curing stress in the composite structure can not be released, so the solidification molding is completed in the composite material. After leaving the mold cavity, the internal solidification stress of the composite structure will be released. After a period of time, the composite structure will appear the phenomenon of deformation, which will affect the shape accuracy and the related mechanical properties of the composite structure. The similar shrinkage ratio model of wing composite structure will produce deformation after solidification which will affect the shape accuracy and further affect the aerodynamic characteristics of the model and the reliability of wind tunnel test data. In this paper, the curing residual stress and deformation of epoxy resin, unidirectional composite, glass fiber orthogonal composite and carbon fiber orthogonal composite were measured by strain gauges, and the equivalent thermal expansion coefficient was obtained. And the corresponding tensile test was done, and the required mechanical properties were obtained. Based on the theoretical model of residual stress of resin matrix composites and the relevant parameters obtained, the solidification deformation of the laminates was analyzed and verified by the method of theoretical analysis and the simulation of large-scale three-dimensional software ANSYS. Considering that the traditional test method to study the solidification deformation of wind tunnel test shrinkage model will waste a lot of time and materials and increase the cost, the finite element analysis method is used to analyze and predict the solidified deformation instead of repeated tests. At the end of the paper, the finite element model is established by ANSYS software, and the solidification deformation prediction of the similar shrinkage model of wing composite structure is carried out, which lays a foundation for the further improvement of the technology.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB332

【參考文獻】

相關(guān)期刊論文 前3條

1 張紀奎;酈正能;關(guān)志東;程小全;王軍;;熱固性樹脂基復(fù)合材料固化變形影響因素分析[J];復(fù)合材料學(xué)報;2009年01期

2 岳廣全;張博明;戴福洪;杜善義;;固化過程中模具與復(fù)合材料構(gòu)件相互作用分析[J];復(fù)合材料學(xué)報;2010年06期

3 王榮秋;固化樹脂收縮率測定的幾種方式[J];纖維復(fù)合材料;1994年02期

，

本文編號：1838233