计算流体力学在化学工程中的应用

计算流体力学(CFD)用于求解固定几何形状设备内的流体的动量、热量和质量方程以及相关的其他方程,已成为研究化工领域中流体流动和传质的重要工具。本文概述了CFD的基本原理以及CFD在化学工程领域方面的应用,重点介绍了CFD在搅拌槽、换热器、蒸馏塔、薄膜蒸发器、燃烧等方面的应用。     

丁二烯萃了精馏塔的流体力学计算

本文考虑了二烯萃取塔真实汽，液相负荷分布和塔板结构，完成了流体力学核算，对实际操作具有一定的指导意义。     

计算流体力学在精馏塔板上的应用

本文对计算流体力学 (CFD)在精馏塔板上的应用进行了综述。介绍了计算流体力学对塔板流场的模拟 ,数值解法、实验研究及对塔板传质过程的理论研究。同时给出了典型数学模型的主要计算结果 ,并对以后的研究工作给出了建议     

利用计算流体力学方法研究精馏塔板上的液相流动

A computational fluid-dynamics model is presented for predicting the two-phase two-dimensional liquid phase flow on a distillation column tray based on the modification of Navier-Stokes Equation by considering both the resistance and the enhanced turbulence created by the uprising vapor. Experimental measurement of the local liquid phase velocity on an air-water simulator of 1.2 m in divaneter by using the hot film anemometer is briefly described. Two of the conventional fluid-dynamic constants are readjusted for the case of liquid flow on a tray byfitting the experimental data. The predicted local liquid phase velocity and direction of flow by the present model are confirmed satisfactorily by the authors‘ experimental measurements and by the data from literature. By the aid of the present model, the concentration field on the tray can be computed for the evaluation of the enhancement of liquid phase concentration across a tray. The advantages of applying computational fluid-dynamics to tray column design are discussed.     

丁二烯萃取精馏塔的流体力学计算

本文考虑丁二烯萃取塔真实汽、液相负荷分布和塔板结构，完成了流体力学核算，对实际操作具有一定的指导意义     

计算流体国学在精馏塔板上的应用

本文对计算机流体力学（CFD）在精馏塔板上的应用进综述。介绍了计算流体力学对塔板流场的模拟,数值解法,实验研究及对塔板传质过程的理论研究。同时给出了典型数学模型的主要计算结果,并对以后的研究工作给出了建议。     

计算流体力学(CFD)在精馏塔板上的应用

介绍了计算流体力学(CFD)数学模型的发展状况,以及计算流体力学(CFD)在塔板流场上的应用。总结了相关实验研究进展,并对塔板流场今后的研究进行了展望。     

搅拌反应器内计算流体力学模拟技术进展

综述了计算流体力学(CFD)技术应用在搅拌反应器的进展情况。重点对搅拌反应器内流动场模拟的各种处理方法,包括"黑箱"模型法、内外迭代法、多重参考系法和滑移网格法,进行了介绍与评价,指出了各种方法所具有的特点及存在的问题。阐述了搅拌反应器内CFD技术的发展方向,并就国内的研究现状进行了简单概述。     

计算流体力学数值模拟技术在陶瓷梭式窑中的应用

陶瓷间隙式窑炉，尤其是梭式窑炉，是陶瓷窑炉发展的趋势所在.运用计算流体力学（computational fluid dynamics，CFD）数值模拟技术对它进行研究，可以克服由于影响因素众多而难以进行实验研究的缺点.本文通过CFD商用软件FLUENT对窑内的温度、速度和压力流场等进行研究和分析，得出一些较为合理的建议，为今后指导窑炉的设计和陶瓷生产过程提供参考。     

计算流体力学在模拟生化反应器中的应用研究

计算流体力学是生化反应器模拟研究的重要手段，简述了流体力学理论研究概况及其在搅拌式生物反应器，气升式生物反应器中的应用，并指出了进一步研究的方向。     

利用计算流体力学及计算传质的方法研究精馏塔传质效率

It has long been found that the flow pattern of the liquid phase on distillation tray is of great importance on distillation process performance. But until now, there was very few published work on quantitative investigation of this subject. By combining the computational fluid dynamics (CFD) with the mass transfer equation, a theoretical model is proposed for predicting the details of velocity and concentration distributions as well as the tray efficiency of distillation tray column. Using the proposed model, four different cases corresponding to different assumptions of liquid and vapor flowing condition for a distillation tray column were investigated. In Case I, the distributions of velocity and concentration of the incoming liquid from the downcomer and the uprising vapor from the underneath tray spacing are uniform. In Case Ⅱ, the distribution of the incoming liquid is non-uniform but the uprising vapor is uniform. In Case Ⅲ, the distribution of the incoming liquid is uniform but the uprising vapor is non-uniform.In Case IV, the distributions of both the incoming liquid and the uprising vapor are non-uniform. The details of velocity and concentration distributions on a multiple sieve tray distillation column in four different cases were simulated using the proposed model. It is found that the shape of the simulated concentration profiles of vapor and the liquid is quite different from case to case. The computed results also show that the tray efficiency is highly reduced by the maldistribution of velocity and concentration of the incoming liquid and uprising vapor. The tray efficiency for Case Ⅰ is higher than Case Ⅱ or Case Ⅲ, and that for Case Ⅳis the lowest. It also reveals that the accumulated effect of maldistribution becomes more pronounced when the number of column trays increased. The present study demonstrates that the use of computational method to predict the mass transfer efficiency for the tray column, especially for the large one, is feasible.     

Computational Fluid-dynamics of Liquid Phase Flow on Distillation Column Trays

A computational fluid-dynamics model is presented for predicting the two-phase two-dimensional liquid phase flow on a distillation column tray based on the modification of Navier-Stokes Equation by considering both the resistance and the enhanced turbulence created by the uprising vapor. Experimental measurement of the local liquid phase velocity on an air-water simulator of 1.2m in diameter by using the hot film anemometer is briefly described. Two of the conventional fluid-dynamic constants are readjusted for the case of liquid flow on a tray by fitting the experimental data. The predicted local liquid phase velocity and direction of flow by the present model are confirmed satisfactorily by the authors' experimental measurements and by the data from literature. By the aid of the present model, the concentration field on the tray can be computed for the evaluation of the enhancement of liquid phase concentration across a tray. The advantages of applying computational fluid-dynamics to tray column design     

Computational Fluid Dynamics Simulation of 13CO Distillation in Structured Packing

Physical 3D models were established for corrugated packing used in the enrichment of the isotope ¹³C. Computational fluid dynamics (CFD) simulation results indicated that common corrugated packing was not well wetted when used for isotope distillation. It is concluded that liquid misdistribution in the packed tower results from the structure of the packing rather than from the height of the packing beds. The existence of entrainment was also demonstrated by CFD simulation. It is proved that mass transfer equations based on the Nusselt theory are not suitable for distillation calculation in such a corrugated packing system. By comparison, the recently developed structured packing model with a corrugation geometry based on the right‐angled triangle, known as Zigzag‐pak, describes vapor‐liquid distribution properties well and has significant advantages over common corrugated packing due to its better liquid distribution character.     

混合箱塔板流体力学性能实验研究

研究开发了一种大通量高效率的混合箱塔板 ,它的非传质区仅占塔截面积的 5 %左右 ,在塔板上设计了用于提高气液传质效率的混合箱结构。在冷模试验塔内对混合箱塔板的压降、漏液、雾沫夹带以及降液管清液层高度等流体力学性能进行了试验 ,试验表明该塔板的漏液和雾沫夹带都比传统筛板有所减少 ,且通量大幅度提高     

Computational Fluid Dynamics versus Experiment: An Investigation on Liquid Weeping of Nye Trays

The weeping phenomenon was investigated using some experimental tests and a numerical model. The tests were performed within a 1.22‐m‐diameter pilot‐scale column including two chimney trays and two Nye test trays with an air‐water system. The rates of weeping were measured in the Nye trays with two heights of the weir and a hole area of 5 %. Moreover, the weeping rates in the outlet and inlet halves of the Nye tray and the total weeping rate were calculated. In the next step, an Eulerian‐Eulerian computational fluid dynamics (CFD) technique was used. The results show good agreement between the attained CFD findings and the experimental data.     

高效导向筛板在醋酸甲酯精馏塔技术改造中的研究与应用

在计算机上模拟优化设计了醋酸甲酯的精馏方案。采用新型高效导向筛板塔解决了含发泡物质物系的精馏难点。技术改造后扩产约５０％、节能４０％左右并提高了产品质量和回收率。技术改造投资３０万元、年增经济效益４００万元，投资回收期不到１个月。