• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Heat Transfer >Numerical Simulation of Condensation for R410A in Horizontal Round and Flattened Minichannels
【24h】

Numerical Simulation of Condensation for R410A in Horizontal Round and Flattened Minichannels

机译：R410A在水平圆形和扁平微型通道中冷凝的数值模拟

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Heat transfer characteristics for condensation for R410A inside horizontal round (d_h = 3.78 mm) and flattened tubes (aspect ratio (AR) = 3.07, 4.23, and 5.39) with larger horizontal than vertical dimensions at a saturation temperature of 320 K are investigated numerically. The flattened tube has flat upper and lower walls and circular end walls. The heat and mass transfer model for condensation is verified by comparing numerical heat transfer coefficients of round tubes with experimental data and empirical correlations. Liquid-vapor interfaces and local heat transfer coefficients are also presented to give a better understanding of the condensation process inside these tubes. The results indicate that local heat transfer coefficients increase with increasing mass flux, vapor quality, and aspect ratio. The enhancement of heat transfer coefficients for flattened tubes is more pronounced at higher mass flux and vapor quality values (about 1.5 times the heat transfer coefficients for round tubes when G = 1061 kg m~(-2) s~(-1), x ≥ 0.8). Unlike in the round tubes, the liquid film in the flattened tube accumulates at the sides of the bottom surface and at the middle of the top surface of the channels when vapor quality is low. Peak values of liquid film thickness in flattened tubes are obtained around angles about the centroid θ of 70 deg and 117 deg, where θ=0 deg is upward.
机译：在饱和温度为320 K的条件下，数值研究了R410A在水平圆形区域（d_h = 3.78毫米）和水平尺寸大于垂直尺寸的扁平管（纵横比（AR）= 3.07、4.23和5.39）内部冷凝的传热特性。扁平管具有平坦的上壁和下壁以及圆形的端壁。通过将圆管的数值传热系数与实验数据和经验相关性进行比较，验证了冷凝物的传热传质模型。还介绍了液体-蒸汽界面和局部传热系数，以更好地了解这些管内的冷凝过程。结果表明，局部传热系数随质量通量，蒸气质量和纵横比的增加而增加。在较高的质量通量和蒸汽质量值下，扁平管的传热系数的增强更为明显（当G = 1061 kg m〜（-2）s〜（-1），x时，约为圆形管的传热系数的1.5倍。 ≥0.8）。与圆管不同，当蒸汽质量低时，扁平管中的液膜会积聚在通道底面的侧面和顶面的中间。围绕约70度和117度的质心θ的角度获得扁平管中液膜厚度的峰值，其中θ= 0度向上。

著录项

  • 来源
    《Journal of Heat Transfer》 |2017年第2期|021501.1-021501.9|共9页
  • 作者

    Wei Li; Jingzhi Zhang; Guanghui Bai; Jin-liang Xu; Terrence W. Simon; Junye Li; Jin-jia Wei;

  • 作者单位

    Department of Energy Engineering, Zhejiang University, Hangzhou 310027, China;

    Department of Energy Engineering, Zhejiang University, Hangzhou 310027, China;

    Huadian Electric Power Research Institute Zhejiang, Hangzhou 310030, China;

    The Beijing Key Laboratory of Multiphase Flow and Heat Transfer for Low Grade Energy Utilization, North China Electric Power University, Beijing 102206, China;

    Mechanical Engineering Department, University of Minnesota, 111 Church Street S.E., Minneapolis, MN 55455;

    Department of Energy Engineering, Zhejiang University, Hangzhou 310027, China;

    State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, 710049, China;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号