﻿ 锯齿型翅片流动均匀性数值分析
 舰船科学技术  2019, Vol. 41 Issue (3): 97-100 PDF

1. 武汉第二船舶设计研究所，湖北 武汉 430064;
2. 武汉理工大学 材料复合新技术国家重点实验室，湖北 武汉 430070;
3. 郑州轻工业学院 能源与动力工程学院，河南 郑州 450002

Numerical analysis of flow uniformity in offset strip fins
JIANG Guo-bao1, ZHOU Ai-min1, SHEN Xu-dong1, TAN Jin-ting2, YUAN Pei3
1. Wuhan Second Ship Design and Research Institute, Wuhan 430064, China;
2. The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China;
3. School of Energy and Power Engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, China
Abstract: As an important part of the ship guarantee system, improvements in heat transfer enhancement is significant to ship air conditioning. The flow uniformity of fin channel in plate-fin heat exchanger directly affects the heat transfer efficiency of heat exchangers. The inlet flow uniformity influence on offset strip fins with different Re numbers is discussed in this paper. The results show that flow uniformity become less than 5% after five geometric cycles with 25% inlet flow uniformity difference and the flow uniformity has little influence on pressure drop.
Key words: plate-fin heat exchanger     offset strip fins     flow uniformity
0 引　言

 图 1 锯齿形翅片的结构示意图 Fig. 1 Diagram of offset strip fin

1 物理模型

 图 2 翅片结构及计算区域 Fig. 2 Fin structure and computational domain

 ${\rm{div}}\left( {\rho U\varPhi } \right) = {\rm{div}}\left( {\varGamma {\rm{grad}}\varPhi } \right) + S{\text{。}}$ (1)

2 模型验证

 图 3 试验台 Fig. 3 Test section

 $Re = \frac{{u{D_e}}}{\nu }{\text{。}}$ (2)

 ${D_e} = \frac{{2sh}}{{sh}}{\text{。}}$ (3)

 $\Delta p = \left[ {{p_i} - {p_{(i - 1)}}} \right]/L{\text{。}}$ (4)

3 结果与讨论

 ${D_i}{\rm{ = }}\frac{{{{\dot m}_{{i}}}}}{{\sum\nolimits_{{{j = 1}}}^6 {{{\dot m}_{{i}}}{\rm{/6}}} }}{\text{。}}$ (5)

 $STD=\left[\frac{1}{10}\sum\limits_{i=1}^{6}{{({{D}_{i}}-1)}^{2}}\right]^{{\scriptstyle{}^{1}\!\!\diagup\!\!{}_{2}\;}}{\text{。}}$ (6)

 图 4 不同截面整体均匀性 Fig. 4 The uniformity of different cross section

 图 5 z=28.5 mm截面流量图 Fig. 5 The flow diagram in z=28.5 mm cross section

 图 6 y=3.2 mm截面z向速度图 Fig. 6 The velocity diagram in y=3.2 mm cross section

 图 7 不同截面压降偏差图 Fig. 7 The pressure drop deviation diagram in different cross section
4 结　语

本文给出了板翅式换热器常用的锯齿形翅片（65JC1403）在不同雷诺数下，几种不均匀入口对流动的影响。主要结论如下：在相同的入口平均雷诺数情况下，不同的入口条件流体达到均匀的流动长度不同，在经过24 mm时流体整体均匀性小于0.05；在不同雷诺数条件下，相似的入口条件流体达到均匀的流动长度基本相等，与平均雷诺数关系不大；不均匀入口对流体流动压降影响不显著。值得指出：本文的研究工作是在没有换热的单相流动情况下进行的，在舰船空调换热器两相及有换热的情况下设计优化过程还需要进一步的研究。

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