基于动网格技术的电除尘器泄爆过程数值仿真  

Numerical Simulation of Explosion Venting in an Electrostatic Precipitator based on Dynamic Mesh Technique

作　　者：杨凯[1] 李强 丁志江[3] 肖立春[3] 

机构地区：[1]燕山大学机械工程学院,河北秦皇岛066004 [2]燕山大学国家冷轧板带装备及工艺工程技术研究中心,河北秦皇岛066004 [3]燕山大学环境与化学工程学院,河北秦皇岛066004

出　　处：《热能动力工程》2017年第8期63-70,共8页Journal of Engineering for Thermal Energy and Power

基　　金：河北省自然科学基金资助项目(E2015203236);河北省重大技术创新项目(10273920z)

摘　　要：为研究电除尘器在泄爆过程中流场与泄爆阀的动态特性,基于动网格技术,建立了泄爆过程中流体与阀体间的耦合关系,对泄爆过程进行了三维瞬态模拟,对不同爆炸压力、阀盖行程、弹簧刚度以及气体介质温度对泄爆过程的影响进行了分析。对初始温度为2 000 K,相对压力40 kPa的空气介质,阀盖行程60 mm泄爆阀在0.152 s内完成泄爆并复位,泄放体积约为2.95 m^3。分析结果表明:随着内部压力的增大,泄爆时间随之呈线性增加;增大阀盖的行程,阀盖前期运动情况不变,中后期泄放速率增大,总体泄放时间降低,且降低趋势逐渐平缓;一定范围内改变弹簧的刚度对泄爆效果无明显影响;随着气体介质温度的降低,泄爆时间与泄放速率迅速增加,温度从2 000 K降低到300 K时,泄爆时间从0.15 s增加到0.35 s,但泄放过程最大马赫数基本不变。To analyze the flow field and dynamic behavior of venting valve in ESP explosion venting,simulation study on the venting process was conducted by introducing the dynamic mesh technique. The coupling relation between gas and valve was built based on the fluid mechanics and Newtonian mechanics. Numerical model based on dynamic mesh was proved to be reliable and accurate by comparing with confirmatory test's result. The flow field and dynamic behavior of valve were obtained. The venting results at different explosion pressure were discussed. Furthermore,the effects of valve parameters such as the valve stroke,spring stiffness,and gas medium temperature on the venting process were analyzed. Under the operating temperature of 2 000 K and explosion pressure of 40 kPa,the venting valve's reset time was 0. 152 s with travel distance of 60 mm and discharged volume of 2. 95 m^3. Results showed that the venting time has an almost linear relation with the explosion pressure. The increase of valve stroke will end up with the increase of discharge rate in the middle and later periods. Meanwhile,the overall venting time is decreased and then followed by leveling off. Besides,the stiffness has no significant effect on venting time within certain limits. With the decrease of gas temperature,the venting time and discharge rate increase rapidly. The venting time increase to 0. 35 s in the case of 300 K. However,the largest Mach numbers in all cases remain almost unchanged.

关 键 词：泄爆 动网格 电除尘器 数值模拟 

分 类 号：O353.4[理学—流体力学]