發(fā)布時間：2018-03-26 07:22

  本文選題：旋轉(zhuǎn)錯流　切入點：旋轉(zhuǎn)速度　出處：《膜科學(xué)與技術(shù)》2017年04期

【摘要】：在不同盤間距和轉(zhuǎn)速下,利用MRF、多孔介質(zhì)模型和基于k-ω湍流模型對旋轉(zhuǎn)錯流式膜分離過程的出水階段和不出水"沖刷"階段進(jìn)行了流體動力學(xué)分析,揭示其內(nèi)部流動規(guī)律,并與測定的結(jié)果比較,顯示模擬結(jié)果與試驗吻合較好.分析結(jié)果表明:在出水階段,當(dāng)盤間距每減小5mm,在60r/min時流速的峰值會減小約10%,但隨著膜盤轉(zhuǎn)速的增加,這種差異性逐漸減小,同時膜盤間主要流速范圍沿盤徑向外推移.在不出水階段,流速的峰值隨盤間距減小而增加,而轉(zhuǎn)速的增加使曲線差異性減小,同時膜表面剪切力會隨轉(zhuǎn)速增加而增大,可增強對膜表面的沖刷,減緩膜通量的衰減;膜盤間距對剪切力的影響在低轉(zhuǎn)速下較明顯,但隨著轉(zhuǎn)速提高,曲線差異性逐漸變小,當(dāng)轉(zhuǎn)速達(dá)到500r/min時曲線的峰值差異已減小到約1Pa.另通過實驗表明,轉(zhuǎn)速和出水量的變化具有不一致性,轉(zhuǎn)速大于400r/min時,出水量開始明顯減小,說明設(shè)備運行時轉(zhuǎn)速不宜過大.并在此基礎(chǔ)上嘗試對加入擾流板的改進(jìn)設(shè)備結(jié)構(gòu)進(jìn)行模擬,模擬結(jié)果顯示,改進(jìn)結(jié)構(gòu)可使膜表面的剪切力峰值增加約1.5Pa,進(jìn)一步緩解膜通量的衰減.
[Abstract]:The use of MRF in different space and speed, and the porous media model and the water phase k- turbulence model of rotary cross flow membrane separation process and no water "scour" stage based on fluid dynamics analysis, reveal the internal flow law and determination results compared, show the simulation results are in agreement with experimental ones good. The analysis results show that: in the water phase, when the plate spacing for each reduced 5mm, peak velocity in 60r/min will be decreased by about 10%, but with the increasing film plate speed, the difference decreases gradually, while the main flow velocity along the membrane disc disc diameter goes outward. In the water phase, with the peak velocity the plate spacing decreases, while the speed of the increase curve difference decreases, the surface shear stress and the film will increase with increasing speed can be enhanced on membrane surface erosion, slow attenuation of membrane flux; membrane plate spacing on shear stress At low speeds is obvious, but with the speed increase, the curve difference becomes smaller, the peak difference when the speed is 500r/min curve has been reduced to about 1Pa. in the other experiment shows that the speed and the change of water is not consistent, the speed is greater than 400r/min, the water began to decrease, indicating when the equipment is running speed should not be too large. And on this basis, try to improve the equipment structure to simulate the spoiler added, the simulation results show that the improved structure can make the shear stress peak membrane surface increased by about 1.5Pa, the attenuation of membrane flux further ease.

【作者單位】： 上海海事大學(xué)海洋科學(xué)與工程學(xué)院;
【基金】：廣西壯族自治區(qū)水利科技項目資助(201316)
【分類號】：TQ028.8
，

本文編號：1666911