Assignment Instructions/ Description
Image transcription textAn aluminum triangular fin is used to cool an electronic package which dissipates 7.5W. The fin is
mounted on one of the package's rectangular surfaces. The base of the fin measures 2 cm x 10
cm and its length is 12 cm. The fin is cooled by convection with a heat transfer coefficient 9.2
W/m?/K and the ambient temperature is 18 "C. Determine the surface temperature of the
package.... Show moreImage transcription textExample problem LMJ 3.51: Heat transfer from a triangular fin:
An aluminum triangular fin is used to cool an electronic package which dissipates 3W. The fin is mounted on one of the
package's rectangular surfaces. The base of the fin measures 1 cm x 5 cm and its length is 9 cm. The fin is cooled by convection
with a heat transfer coefficient 8.5 W/m/K and the ambient temperature is 23 *C. Determine the surface temperature of the
package.... Show moreImage transcription textKNOWN: triangular fin attached to one side of an electronics package to enhance cooling. Dimensions and heat rate known.
FIND What is the temperature at the base of the fin needed to dissipate 3W?
Th = T( x=0) = ?
SCHEMATIC:
23 C = TAX
electronic
8.6 W = h
maroc
3W
9 cm
ASSUMPTIONS: steady state, no heat generation, no radiation.
. Entire heat from electronics (3 W) is dissipated by conduction through fin and convection into air
. Neglect heat losses from edges of fin and from other sides of package
PROPERTIES aluminum: k = 236 W/m/k
ANALYSIS: because this is a triangular fin, it is easiest to use the fin efficiency chart
D need to Find c From chart
( Triangular Fin )
- need Le= L = 0.09 m
Ale
= Lty, = 0,09 m. 0.01 m / 2
Lyth= 0.29
solve for To
() read ME From chart
(2 ) calculate ? = 3 W= hAs (T. - To)7:
3
To = TA +
3 W
h AF NF
Ag = 2 W V 1 2 + ( ) 2
= 230C + 3W
= 0.00901 m2
85W
To = 64. 20 0
MOC
095 - 0, 00901 12... Show moreSolve the first image, second and third image is an example of the same style of problem����