摘要
建立了二维不可压缩后向台阶流动的数值模型，在Re=100—400内研究了雷诺数、台阶高度（S）、平板间高度（H）变化对台阶下游底面努塞尔数Nu分布的影响．结果表明：台阶扩张比ER一定，台阶下游上壁面出现次回流区后，舭分布曲线下降段的曲折点位置固定，增大Re能提高曲折点上游的№，但对曲折点下游Nu影响不大；保持S不变，减小H，ER由1．33增加到3．00，Nu的变化范围增大，峰值向上游移动；保持日不变，增大S，NuH变化分成2部分，ER由1．33增加到2．00，NuH峰值基本不变，位置向下游移动，ER由2．00增加到3．00，NuH峰值快速增加，位置基本不变．
A two-dimensional incompressible numerical model of the backward-facing step flow was established. The influences of Reynolds number, step height（S） and channel height（H） on the Nusseh number at the bottom wall surface downstream of the step were discussed in the laminar flow range of Re from 100 to 400. The results show that for constant expansion ratio of ER, the positions of inflection points for Nusselt number curves are stable when an additional reeireulation region appears on the upper wall. Increasing the Reynolds number can improve the upstream Nusselt number of inflection points, but has slight effect on the downstream Nusselt number. When S is constant with decreased H, ER increases from 1.33 to 3.00, and the variation range of Nusseh number（Nu） increases with the position of Nu peak moving upstream. When H is constant with increased S, the variation range of Nusselt number（Nun） can be divided into two parts. With the increasing of ER from 1.33 to 2.00, the value of Nun peak essentially remains unchanged, while the position of Nun peak moves downstream. With the increasing of ER from 2.00 to 3.00, the value of Nun peak rapidly increases, while the position of Nun peak changes slightly.
出处
《江苏大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2014年第4期397-402,共6页
Journal of Jiangsu University：Natural Science Edition
基金
国家自然科学基金资助项目(51176079)
江苏高校优势学科建设工程项目(苏政办发[2011]6号)
关键词
后向台阶
层流
传热特性
数值模拟
台阶高度
平板间高度
backward-fatting step
laminar flow
heat transfer characteristics
numerical simulation
step height
channel height
