{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

class 6 - Extended Surfaces Chapter Three Section 3.6...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Extended Surfaces Chapter Three Section 3.6
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
How is heat transfer enhanced? Assume T s is fixed. Computer chip = lots of heat generated Increase h -Higher fluid velocity, lower fluid temperature Increase surface area -Add extended surface, usually easier and cheaper
Background image of page 2
Extended surfaces may exist in many situations but are commonly used as fins to enhance heat transfer by increasing the surface area available for convection (and/or radiation). They are particularly useful when h is small. Straight fins of (a) uniform and (b) non-uniform cross sections; (c) annular fin , and (d) pin fin of non-uniform cross section. Extended Surfaces = Conduction within boundary + Convection between boundary and surroundings
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Assume: h and k are constant steady state negligible radiation no heat generation What is the energy balance for this system? a) b) c) d) e) g out in st E E E E + - = out in st E E E - = out in E E - = 0 g in E E + = 0 g out E E + = 0
Background image of page 4
Assume: h and k are constant steady state negligible radiation no heat generation What is E in ?
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}