摘要:采用分段一集合計(jì)算方法,對(duì)二步法三維編織變厚度變截面薄壁殼體RTM充模工藝過程進(jìn)行了較深
人的理論研究。提出了較準(zhǔn)確的樹脂流動(dòng)速度、樹脂充模時(shí)問和樹脂流動(dòng)壓力計(jì)算方程。數(shù)值預(yù)測(cè)值與充模試
驗(yàn)結(jié)果具有良好的一致性,所推導(dǎo)理論方程為合理設(shè)計(jì)RTM充模土藝參數(shù)提供了理論依據(jù). 關(guān)鍵詞:復(fù)合材料;二步法三維編織;RTM;分段一集合計(jì)算方法;數(shù)值模擬 中圖分類號(hào):TS.330. 1文獻(xiàn)標(biāo)識(shí)碼:八 NUMERICAL SIMULATION AND EXPERIMENTAL STUDY OF RESIN FLOW IN RTM
PROCESSING FOR TWO STEP 3D BRAID SHELL PREFORM WITH VARYING SECTION ZHANG Guoli,Lilu,I_I Xueming
(Composites Research Institute of Tianjin Polytechnic University, Tianjin 300160,China)
Abstract:hhc filling process of RT M for the two step 3D braid shell prcform with a varying section. was investi gated theoretically by employing a calculating method of divide-integratim.Several formulation、related to the resinvelocity,resin filling time and resin flow pressure were proposed accurately. Good agreement was found between the experimental results and numerical predictive values. The deduced formulations could provide the theoretical basis for suitably designing RTM filling parameters.
Keywords:composites; two. step 3D braiding;RTM;divide-integration method;numerical simulation
采用增強(qiáng)纖維三維空間交織成整體網(wǎng)狀結(jié)構(gòu)的三維整體編織(或機(jī)織)預(yù)成型體,通過合理選擇不同的增強(qiáng)纖維、樹脂基體和交織結(jié)構(gòu),可制造具有整體機(jī)械性能優(yōu)異、結(jié)構(gòu)尺寸穩(wěn)定性好、耐熱燒蝕、耐低溫和優(yōu)良的介電性能的新型結(jié)構(gòu)和功能三維編織(或機(jī)織)復(fù)合材料。目前三維整體編織(或機(jī)織)變截面薄壁殼體RTM成型復(fù)合材料已替代傳統(tǒng)的21)織物鋪層殼體復(fù)合材料川,成為運(yùn)載火箭殼體、復(fù)合裙、雷達(dá)天線罩等構(gòu)件的首選承載結(jié)構(gòu)之一。由于此類型殼體結(jié)構(gòu)件尺寸大、纖維體積含量高、型面曲線和壁厚公差要求嚴(yán)格川,采用金屬閉模RTM成型工藝進(jìn)行加工時(shí),提高樹脂對(duì)纖維預(yù)制件的宏觀和微觀浸滲程度川,是確保復(fù)合材料質(zhì)量和性能的技術(shù)關(guān)鍵。為解決RTM工藝充模過程中樹脂流動(dòng)規(guī)律的可預(yù)見性和可控制性的技術(shù)難題,國(guó)內(nèi)外研究者多采用有限差分法、有限元控制體積法川、邊界元法和貼體坐標(biāo)法等數(shù)值模擬技術(shù),實(shí)時(shí)地對(duì)形狀簡(jiǎn)單的模腔內(nèi)樹脂流動(dòng)形狀和位置、樹脂流動(dòng)速度場(chǎng)、壓力場(chǎng)和溫度場(chǎng)的分布進(jìn)行預(yù)測(cè),以上數(shù)值方法往往程序編制復(fù)雜,計(jì)算機(jī)模擬計(jì)算耗時(shí)較長(zhǎng)五月。本文作者采用分段一集合計(jì)算方法對(duì)RTM工藝充模過程中樹脂流動(dòng)進(jìn)行了理論分析和試驗(yàn)研究,獲得了典型三維整體編織變截面薄壁殼體樹脂流動(dòng)規(guī)律,為優(yōu)化工藝設(shè)計(jì)提供重要的理論依據(jù)。