【摘要】：多孔介質(zhì)在生產(chǎn)生活以及科技發(fā)展中的應(yīng)用十分廣泛,隨著能源、化工、冶金和原子能等領(lǐng)域技術(shù)的發(fā)展,以及近代工農(nóng)業(yè)生產(chǎn)技術(shù)的進(jìn)步,大量多孔介質(zhì)的傳熱傳質(zhì)問(wèn)題逐漸出現(xiàn),進(jìn)一步促進(jìn)了多孔介質(zhì)學(xué)科的形成和發(fā)展,使其成為當(dāng)今科學(xué)技術(shù)中令人矚目的研究熱點(diǎn)之一.通過(guò)實(shí)驗(yàn)獲得準(zhǔn)確的實(shí)驗(yàn)圖像和數(shù)據(jù),并使用相應(yīng)軟件對(duì)實(shí)驗(yàn)所得數(shù)據(jù)和流體流動(dòng)圖像進(jìn)行深度分析,這樣既有真實(shí)可靠的實(shí)際數(shù)據(jù),又有直觀的理論的支持,使對(duì)多孔介質(zhì)的研究更為完善.實(shí)驗(yàn)結(jié)合粒子圖像測(cè)試技術(shù)和折射率匹配技術(shù)對(duì)叉排排列玻璃球多孔介質(zhì)填充床內(nèi)的流體流動(dòng)轉(zhuǎn)變過(guò)程進(jìn)行流場(chǎng)測(cè)試,并提取數(shù)據(jù),采用Tecplot軟件對(duì)提取數(shù)據(jù)進(jìn)行處理,得出流體流動(dòng)機(jī)理的轉(zhuǎn)變過(guò)程.實(shí)驗(yàn)固相為由直徑25 mm水晶玻璃球叉排堆積而成的填充床,液相為65%苯甲醇和35%無(wú)水乙醇配制的匹配液.液相與固相的折射率都為1.477,成功消除由于折射率不匹配引起的激光光線偏折.實(shí)驗(yàn)得到雷諾數(shù)為4.7 ≤Re ≤1000時(shí)球床內(nèi)流場(chǎng)圖,對(duì)比不同雷諾數(shù)時(shí)流場(chǎng)和流線變化得出:隨著雷諾數(shù)的增加,流線變得越來(lái)越紊亂;當(dāng)雷諾數(shù)在220以上時(shí),球床內(nèi)漩渦在尺寸變化上出現(xiàn)突躍,在位置和形態(tài)變化表現(xiàn)出隨機(jī)特征,預(yù)示進(jìn)入了穩(wěn)定的湍流.
[Abstract]:Porous media is widely used in production and life and in the development of science and technology. With the development of technologies in the fields of energy, chemical industry, metallurgy and atomic energy, as well as the progress of modern industrial and agricultural production technology, The problem of heat and mass transfer in a large number of porous media has emerged gradually, which has further promoted the formation and development of the subject of porous media and has become one of the most attractive research hotspots in science and technology nowadays. The accurate experimental images and data are obtained through experiments, and the experimental data and fluid flow images are analyzed in depth by using the corresponding software. This is not only true and reliable actual data, but also intuitive theoretical support. The study of porous media is more perfect. In the experiment, the flow field of the fluid flow transition in the packed bed of the porous media packed with the cross-arranged glass spheres was measured with particle image testing technique and refractive index matching technique, and the data were extracted, and the extracted data were processed by Tecplot software. The transition process of fluid flow mechanism is obtained. The experimental solid phase is a packed bed packed with 25 mm crystal glass spheroidal cross row. The liquid phase is composed of 65% benzyl alcohol and 35% anhydrous ethanol. The refractive index of both liquid and solid phase is 1.477. the laser beam deflection caused by refractive index mismatch is successfully eliminated. The flow field diagram of spherical bed is obtained when Reynolds number is 4. 7 鈮，

本文編號(hào)：2335932