化學工業(yè)
來源出版物:Chinese Journal of Chemical Engineering,2015,23(4): 461-470
聯(lián)系郵箱:Kun Luozjulk@zju.edu.cn
封面介紹:表面更新頻率是液膜的基本特性,加速表面更新是強化氣液兩相傳質(zhì)的重要手段.封面圖片給出的是數(shù)值模擬圓盤表面液膜更新頻率分布特性.普通圓盤上附壁膜加速區(qū)更新最快;開窗圓盤開窗區(qū)域能形成自由膜,較附壁膜具有更快的表面更新,顯現(xiàn)圓盤開窗后的強化.詳見本期1407-1416頁.
圓盤反應(yīng)器液膜表面更新數(shù)值模擬
鄧斌,戴干策
以圓盤反應(yīng)器的開發(fā)和放大為背景,通過理論分析將液膜更新頻率與液膜變形相關(guān)聯(lián),運用VOF模型研究豎直旋轉(zhuǎn)圓盤液膜更新頻率空間分布特性;將量綱分析與數(shù)值模擬相結(jié)合考察影響普通圓盤液膜平均更新頻率的相關(guān)因素;從表面更新的角度研究自由膜與附壁膜的差異,優(yōu)化圓盤結(jié)構(gòu).結(jié)果表明:圓盤表面液膜加速區(qū)液膜更新頻率最快,較其他區(qū)域高150%,較平均值高75%;獲得了普通圓盤液膜平均更新頻率表達式;圓盤開窗形成自由膜,更新頻率比附壁膜高40%以上;相同面積圓形窗區(qū)域自由膜更新頻率比扇形窗自由膜高34%,但是扇形窗自由膜對附壁膜強化作用更明顯.
反應(yīng)器;數(shù)值模擬;傳質(zhì);表面更新;自由膜;附壁膜
來源出版物:化工學報,2015,66(4): 1407-1416
聯(lián)系郵箱:戴干策,gcdai@ecust.edu.cn
Accurate level set method for simulations of liquid atomization
Changxiao Shao,Kun Luo,Jianshan Yang,et al.
Computational fluid dynamics is an efficient numerical approach for spray atomization study,but it is challenging to accurately capture the gas-liquid interface. In this work,an accurate conservative level set method is introduced to accurately track the gas-liquid interfaces in liquid atomization. To validate the capability of this method,binary drop collision and drop impacting on liquid film are investigated. The results are in good agreement with experiment observations. In addition,primary atomization(swirling sheet atomization)is studied using this method. To the swirling sheet atomization,it is found that Rayleigh-Taylor instability in the azimuthal direction causes the primary breakup of liquid sheet and complex vortex structures are clustered around the rim of the liquid sheet. The effects of central gas velocity and liquid-gas density ratio on atomization are also investigated. This work lays a solid foundation for further studying the mechanism of spray atomization.
Computational fluid dynamics; Level set method; Spray atomization; Interface capture; Breakup