CIESC Journal ›› 2019, Vol. 70 ›› Issue (4): 1331-1339.DOI: 10.11949/j.issn.0438-1157.20181053

• Fluid dynamics and transport phenomena • Previous Articles     Next Articles

Enhancement on steam dropwise condensation heat transfer with superhydrophobic surfaces of PVDF hollow fiber heat exchange tubes

Yexia CHAI1,2(),Huayan CHEN1,3(),Yue JIA1,3,Dandan LI1,2,Chunrui WU1,3,Xiaolong LYU1,3   

  1. 1. State Key Laboratory of Separation Membranes and Membrane Processes, Tianjin 300387, China
    2. School of Environmental and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300387, China
    3. School of Materials Science and Engineering, Tianjin Polytechnic University, Tianjin 300387, China
  • Received:2018-09-19 Revised:2018-11-01 Online:2019-04-05 Published:2019-04-05
  • Contact: Huayan CHEN

PVDF中空纤维换热管超疏水表面强化蒸气滴状冷凝传热

柴叶霞1,2(),陈华艳1,3(),贾悦1,3,李丹丹1,2,武春瑞1,3,吕晓龙1,3   

  1. 1. 省部共建分离膜与膜过程国家重点实验室,天津 300387
    2. 天津工业大学环境与化学工程学院,天津 300387
    3. 天津工业大学材料科学与工程学院,天津 300387
  • 通讯作者: 陈华艳
  • 作者简介:<named-content content-type="corresp-name">柴叶霞</named-content>(1992—),女,硕士研究生,<email>821246765@qq.com</email>|陈华艳(1978—),女,副研究员,<email>chenhuayan@tjpu.edu.cn</email>
  • 基金资助:
    国家自然科学基金项目(51408415);天津市自然科学基金项目(17JCYBJC17400)

Abstract:

To improve the heat transfer performance of the plastic heat exchange tube, a composite plastic heat exchange tube with a superhydrophobic surface was prepared by a two-step coating method. Firstly, the porous polyvinylidene fluoride (PVDF) hollow fiber membrane was used as the supporting layer, and polydimethylsiloxane (PDMS) was filled with thermal conductive material nano-ZnO as the skin layer to prepare the composite plastic heat exchange tube with a dense outer skin layer. Secondly, the PVDF composite plastic heat exchange tube with superhydrophobic surface was prepared by investigating the influence of teraethoxysilane (TEOS) and ammonia content, which enhanced the dropwise condensation heat transfer performance of steam. The results showed that the outer surface contact angle of the prepared heat exchange tube can reach 154°. Compared with the heat exchange tubes prepared by the melting method and the NIPS method, the total heat transfer coefficient could be increased by 85.3%—147.3%.

Key words: polyvinylidene fluoride, plastic heat exchange tube, superhydrophobic surface, dropwise condensation, heat transfer coefficient

摘要:

为了提高塑料换热管的传热性能,通过两步涂覆法制备了具有超疏水表面的复合塑料换热管。首先采用多孔PVDF中空纤维膜为支撑层,以导热材料纳米ZnO填充聚二甲基硅氧烷(PDMS)为皮层,制备了具有致密外表皮层的复合塑料换热管。其次为了强化蒸气的滴状冷凝传热,通过考察正硅酸乙酯含量,氨水含量等条件的影响,制备出了具有超疏水表面的PVDF复合塑料换热管。结果表明,所制备的换热管表面接触角可达154°,与熔融法及NIPS法制备的换热管相比,总传热系数可提高85.3%~147.3%。

关键词: 聚偏氟乙烯, 塑料换热管, 超疏水表面, 滴状冷凝, 传热系数

CLC Number: