Symbol

Quantity

SI Units

k

Thermal conductivity

W/mK

X

Size of the heat source in the x-direction

m

Y

Size of the heat source in the y-direction

m

L

Thickness of the heat spreader

m

α

Heat spreading angle

degrees (or radians)

Q

Heat source

W

T

Temperature at the heat source

˚C or Kelvin

T_A

Ambient temperature = isothermal heat sink temperature = 0˚C for all cases considered

˚C

a

Area of heat source

m²