柳宗元作品Forced Convection heat transfer青蛙瓷器
—Internal春天到儿歌
—External大班的数学题
10-5-1Internal Flow Heat Transfer
Where we’ve been ……
成本考核•Introduction to boundary layer, N-S equations Where we’re going:
蒸汽挂烫机•Developing heat transfer coefficient relationships and correlations for internal flow
r o
δ
δ
1、Internal flow in a tube •
•Laminar flow：•Transit region：•Turbulent Flow：
<
小矮人王国
Re2300
<< 2300Re10000
<
10000Re
δ
δ
养肉驴Entrance region:
•Thin boundary layer,high h
入口段的热边界层薄，表面传热系数高。Length of entrance region:
≈/0.05Re Pr
l d ≈/60l d
