基于拟牛顿法气-液直接接触式冷却塔设计实例研究  

A Case Study on Design of Gas-Liquid Direct Contact Condenser Based on Quasi Newton Method

作　　者：刘敦禹[1] 范雪东 章蕾[3] LIU Dunyu;FAN Xuedong;ZHANG Lei(School of Energy and Power Engineering,University of Shanghai for Science and Technology, Shanghai 200093,China;Sumitomo SHI FW Energy Management(Shanghai)Co.,Ltd.,Shanghai 200122,China;Shanghai University,Shanghai 200444,China)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093 [2]住友重机械福惠能源管理(上海)有限公司,上海200122 [3]上海大学材料科学与工程学院,上海200444

出　　处：《锅炉技术》2018年第5期7-14,共8页Boiler Technology

基　　金：上海市浦江人才项目(16PJ1407900)

摘　　要：最优化计算方法是能源与动力专业的基础课程,目前缺乏关于能源装备的实际案例。采用拟牛顿算法求解气-液接触式冷却塔设计问题。首先基于蒸发和冷凝物理过程构建常微分方程,进而采用拟牛顿法求解常微分方程,为改善迭代稳定性,开发一种基于液相温度最大值点的迭代更新算法,具有很好的收敛速度和稳定性。针对国外某台28MWe富氧燃烧电厂实际烟气计算所需冷却塔填料高度。研究发现:L/G对填料高度和烟气出口湿度的影响相似。过低的L/G大大增加填料高度和烟气出口湿度,而过高的L/G并不能有效降低填料高度和烟气出口湿度,存在最优L/G范围。降低液体温度提高了冷却塔出口烟气的冷凝效率,但温度低于10℃,冷凝效率的提升有限。根据L/G与液体温度的关系,获得最优的液体温度为10℃,相应的最优L/G范围为3.4～4.5。Optimization method is the foundation course in the major of Energy and Power Engineering,and currently the real cases related to the energy equipment are scarce.A case study of design of gas-liquid direct contact condenser was performed by the Quasi-Newton method.Ordinary differential equations were firstly constructed based on evaporation and condensation processes,and then were solved by the Newton method.In order to improve the stability of iteration,a new updated method based on the maximum temperature of liquid phase was developed,and the convergence rate as well as the stability was improved.This method was used to calculate the packing height of direct contact condenser in a 28 MWe Oxy-fuel combustion power plant.Results indicate that the influence of L/G on the packing height is similar to flue gas humidity at the outlet of condenser.Low L/G ratio greatly increases packing height and flue gas humidity at the outlet of condenser,while high L/G ratio does not reduce packing height and humidity significantly.Therefore,optimum L/G ratio range may exist.Reducing liquid temperature increases the condensation efficiency for the outlet of condenser,but when the liquid temperature is lower than 10℃,the improvement on the water removal efficiency is limited.Based on the relationship between L/G ratio and liquid temperature,the optimum liquid temperature is 10℃,and its related optimum L/G ratio range is 3.4~4.5.

关 键 词：冷却塔设计 拟牛顿法 直接接触式 

分 类 号：TK172[动力工程及工程热物理—热能工程]