化工进展
化工進展
화공진전
Chemical Industry and Engineering Progress
2015年
10期
3569-3576
,共8页
刘家瑞%赵巍%黄晓东%张华
劉傢瑞%趙巍%黃曉東%張華
류가서%조외%황효동%장화
板壳式换热器%物流分配%传热%数值模拟%优化设计
闆殼式換熱器%物流分配%傳熱%數值模擬%優化設計
판각식환열기%물류분배%전열%수치모의%우화설계
plate and shell heat exchanger(PSHE)%fluid flow distribution%heat exchange%numerical simulation%optimization design
以一种板壳式换热器壳程为研究对象,建立了几何模型并进行了数值模拟,通过对各流道的流量偏差和相对标准差的计算,分析了壳程物流分配的特性,并总结了物流分配特性对换热器的传热效率、整体效能以及压降的影响。模拟与分析结果显示:换热器壳程存在严重的物流分配不均匀现象,这种现象会造成换热器整体效能的下降,同时造成压降的大幅升高,但是对于传热效率的影响很小,总换热量偏移不足3%。为了改善物流分配带来的影响,提高换热器的性能,通过在入口处设置封头和圆弧状条纹板对换热器壳程来进行优化设计。优化分析结果表明:该设计可以改善换热器物流分配不均匀性,并能使换热器效能下降明显降低,压降相对减小,可以为板壳式换热器的优化提供参考。
以一種闆殼式換熱器殼程為研究對象,建立瞭幾何模型併進行瞭數值模擬,通過對各流道的流量偏差和相對標準差的計算,分析瞭殼程物流分配的特性,併總結瞭物流分配特性對換熱器的傳熱效率、整體效能以及壓降的影響。模擬與分析結果顯示:換熱器殼程存在嚴重的物流分配不均勻現象,這種現象會造成換熱器整體效能的下降,同時造成壓降的大幅升高,但是對于傳熱效率的影響很小,總換熱量偏移不足3%。為瞭改善物流分配帶來的影響,提高換熱器的性能,通過在入口處設置封頭和圓弧狀條紋闆對換熱器殼程來進行優化設計。優化分析結果錶明:該設計可以改善換熱器物流分配不均勻性,併能使換熱器效能下降明顯降低,壓降相對減小,可以為闆殼式換熱器的優化提供參攷。
이일충판각식환열기각정위연구대상,건립료궤하모형병진행료수치모의,통과대각류도적류량편차화상대표준차적계산,분석료각정물류분배적특성,병총결료물류분배특성대환열기적전열효솔、정체효능이급압강적영향。모의여분석결과현시:환열기각정존재엄중적물류분배불균균현상,저충현상회조성환열기정체효능적하강,동시조성압강적대폭승고,단시대우전열효솔적영향흔소,총환열량편이불족3%。위료개선물류분배대래적영향,제고환열기적성능,통과재입구처설치봉두화원호상조문판대환열기각정래진행우화설계。우화분석결과표명:해설계가이개선환열기물류분배불균균성,병능사환열기효능하강명현강저,압강상대감소,가이위판각식환열기적우화제공삼고。
This research established the geometric models of the Shell-side of plate and shell heat exchanger(PSHE). Numerical simulations calculated the deviations and the relative standard deviation of the mass flow,the fluid flow distribution performances were analyzed,the influences of fluid flow distribution performance on heat transfer efficiency,pressure drop and effectiveness of PSHE were analyzed. To optimize the design,a head and circular shaped stripe plate installed at the entrance could improve the impacts of fluid flow distribution and improve the performances of plate and shell heat exchanger. It was concluded that the uneven fluid flow distribution on the shell-side of plate and shell heat exchanger could significantly decrease the whole performances and increase the pressure drop, while it had little effects on the heat transfer efficiency,with the offset of the total heat exchange capacity less than 3%. Moreover,the optimization design not only improved the distribution uniformity obviously,but also made the drop of effectiveness and pressure drop less significant.