CAJ | 학술논문

传统的卧式螺旋卸料离心机只能分离沉渣，不能分离浮渣。本文对一种分离轻质固体浮渣的卧螺离心机进行两相数值模拟研究，使用Pro-E软件建立三维模型，应用计算流体力学软件Fluent，基于Euler多相流模型，采用RNG k-ε湍流模型及多重参考系（MRF）方法，模拟分析了这种卧螺离心机内的固液两相体积分数分布以及操作参数和物性参数对流场和分离性能的影响。模拟结果表明：此卧螺离心机适用于高浓度、中粗粒子的分离；流体沉降分层比较明显，水在液池的外层，浮渣在内层；转速差总体上对分离性能影响不大，但不能过低或是过高，保持在30～70r/min是比较好的选择；进料浓度增加，颗粒沉降速度降低，分离效率会下降；小颗粒沉降速度底且易“反混”而分离性能差，较大颗粒沉降速度高，分离性能明显高于小粒径颗粒。
전통적와식라선사료리심궤지능분리침사，불능분리부사。본문대일충분리경질고체부사적와라리심궤진행량상수치모의연구，사용Pro-E연건건립삼유모형，응용계산류체역학연건Fluent，기우Euler다상류모형，채용RNG k-ε단류모형급다중삼고계（MRF）방법，모의분석료저충와라리심궤내적고액량상체적분수분포이급조작삼수화물성삼수대류장화분리성능적영향。모의결과표명：차와라리심궤괄용우고농도、중조입자적분리；류체침강분층비교명현，수재액지적외층，부사재내층；전속차총체상대분리성능영향불대，단불능과저혹시과고，보지재30～70r/min시비교호적선택；진료농도증가，과립침강속도강저，분리효솔회하강；소과립침강속도저차역“반혼”이분리성능차，교대과립침강속도고，분리성능명현고우소립경과립。
Traditional decanter centrifuge is only used to separate heavy sludge rather than floating sludge. This research developed a two-phase numerical simulation on a decanter centrifuge in separating light solid floating sludge. The three dimension software Pro-E was used to build the 3D model. The computational fluid dynamics software Fluent was applied to analyze volume fraction distribution of the solid and liquid phase as well as the effects of operating conditions and fluid parameters on flow field and separation properties. The simulation was based on Euler multiple phase flow model and RNGk-εturbulence model in a multiple coordinate reference system. The simulation results showed that the decanter centrifuge can be used to separate high density and middle-coarse particles;the fluid settling lamination was obvious and water was in the inner side while floating sludge outside of cistern;there was little effect of rotation speed discrepancy on separation properties. Rotation speed discrepancy in the range of 30—70r/min was optimal. With the increase of the feed concentration,particles’ setting velocity and separation efficiency decreased. Low setting velocity for small particles resulted in less separation efficiency and coarse particles had higher separation capabilities because of quick setting velocity.