發(fā)布時(shí)間：2019-07-03 15:10

【摘要】：因?yàn)闃渲鶑?fù)合材料的比強(qiáng)度和比模量相對(duì)于傳統(tǒng)金屬材料要高,現(xiàn)如今已被大量應(yīng)用在航空航天領(lǐng)域,同時(shí)熱壓罐工藝作為制造航空復(fù)合材料結(jié)構(gòu)的主要方法也吸引了大量的學(xué)者研究。隨著研究的深入,人們發(fā)現(xiàn)復(fù)合材料結(jié)構(gòu)在成型過程中,由于本身結(jié)構(gòu)件和模具體積較大且結(jié)構(gòu)復(fù)雜,阻礙了熱壓罐內(nèi)熱氣體的流動(dòng),引起了復(fù)合材料固化溫度分布不均勻,其內(nèi)部產(chǎn)生殘余應(yīng)力且結(jié)構(gòu)發(fā)生變形,嚴(yán)重影響產(chǎn)品的質(zhì)量和性能。為了改善熱壓罐中復(fù)合材料成型的質(zhì)量,同時(shí)保證成本低和周期短,人們提出使用數(shù)值仿真的方法研究熱壓罐工藝的溫度分布,預(yù)報(bào)復(fù)合材料固化過程中可能出現(xiàn)質(zhì)量問題的地方,提出工藝改善意見。本文從三個(gè)方面研究了熱壓罐中復(fù)合材料構(gòu)件和模具的溫度變化及流場(chǎng)的分布規(guī)律。第一部分使用ICEM軟件和Fluent軟件建立了框架式模具在熱壓罐中強(qiáng)迫對(duì)流換熱的有限元模型,依據(jù)罐內(nèi)氣體的流態(tài),采取標(biāo)準(zhǔn)κ-ε湍流模型作為熱壓罐中氣體流動(dòng)模型,隨后驗(yàn)證了模擬結(jié)果的正確性。依據(jù)該模型討論熱壓罐工藝參數(shù)中升/降溫速率和風(fēng)速對(duì)模具溫度分布的影響規(guī)律。第二部分內(nèi)容基于固體熱傳導(dǎo)方程和樹脂固化放熱方程,建立了包括聚酯樹脂和環(huán)氧樹脂層合板的固化模型,驗(yàn)證了模型的正確性。隨后研究了對(duì)流換熱系數(shù)、厚度等工藝參數(shù)對(duì)層合板固化進(jìn)程中的溫度分布和固化度變化。第三部分內(nèi)容利用Fluent軟件對(duì)熱壓罐成型工藝中蒙皮結(jié)構(gòu)的溫度場(chǎng)和流場(chǎng)特性進(jìn)行了模擬分析,并通過在框架式模具通風(fēng)孔處安裝風(fēng)扇的方法來增強(qiáng)熱空氣對(duì)流,改善罐內(nèi)流場(chǎng)分布均勻性和模具型面溫度分布均勻性。計(jì)算結(jié)果表明,合理地布置風(fēng)扇在模具通風(fēng)孔中的位置和控制風(fēng)速,可以調(diào)整框架式模具內(nèi)部區(qū)域流場(chǎng)分布,使模具型面的溫度場(chǎng)更均勻,對(duì)于提高復(fù)合材料構(gòu)件成型質(zhì)量具有重要意義。
[Abstract]:Because the specific strength and modulus of resin matrix composites are higher than those of traditional metal materials, they have been widely used in aerospace field. At the same time, hot pressing tank technology as the main method of manufacturing aviation composite structure has attracted a large number of scholars. With the deepening of the research, it is found that in the molding process, the large volume and complex structure of the composite structure and die hinder the flow of hot gas in the hot pressing tank, resulting in uneven curing temperature distribution of the composite, resulting in residual stress and structural deformation in the composite, which seriously affects the quality and properties of the product. In order to improve the quality of composite material forming in hot pressing tank and ensure the low cost and short cycle, numerical simulation method is proposed to study the temperature distribution of hot pressing tank process, predict the possible quality problems in the curing process of composite materials, and put forward some suggestions for process improvement. In this paper, the temperature variation and flow field distribution of composite components and dies in hot pressing tank are studied from three aspects. In the first part, the finite element model of forced convective heat transfer of frame die in hot pressure tank is established by using ICEM software and Fluent software. According to the gas flow pattern in the tank, the standard k-蔚 turbulence model is used as the gas flow model in the hot pressing tank, and then the correctness of the simulation results is verified. According to the model, the effects of rising / cooling rate and wind speed on the temperature distribution of hot pressing tank are discussed. In the second part, based on the solid heat conduction equation and resin curing heat release equation, the curing model of polyester resin and epoxy resin laminates is established, and the correctness of the model is verified. Then the temperature distribution and curing degree of laminated plates during curing process were studied by convective heat transfer coefficient, thickness and other process parameters. In the third part, the temperature field and flow field characteristics of the skin structure in the hot pressing tank molding process are simulated and analyzed by using Fluent software, and the hot air convection is enhanced by installing the fan at the vent hole of the frame die, and the uniformity of flow field distribution in the tank and the temperature distribution uniformity of the die profile are improved. The calculation results show that the reasonable arrangement of fan position and control wind speed in die vents can adjust the flow field distribution in the internal area of frame die and make the temperature field of die surface more uniform, which is of great significance to improve the molding quality of composite components.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB33

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 陳永輝;王強(qiáng);樸明波;;湍流模型的發(fā)展及其研究現(xiàn)狀[J];能源與環(huán)境;2009年02期

2 張紀(jì)奎;關(guān)志東;酈正能;;熱固性復(fù)合材料固化過程中溫度場(chǎng)的三維有限元分析[J];復(fù)合材料學(xué)報(bào);2006年02期

3 賈成貴,朱振生,王維綱;大型熱壓罐裝置[J];航空制造工程;1997年03期

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本文編號(hào)：2509483