In: Mechanical Engineering
Forced convection
A thin plate is suspended in air at 1 atm. with T? = 15°C. Air
flows on both sides of the plate where the bottom side absorbs a
uniform radiative heat flux of 1542 W/m2. The plate is oriented
parallel to the flow and the length along the flow direction is 60
cm. Consider the plate is negligibly thin and the width of the
plate (perpendicular to the flow) is large, so that the problem can
be considered as a 2D problem.
1. If the temperature of the plate is not to exceed 80°C at any
position, what air velocity would be required? Evaluate the air
properties at 310 K. (3 pts)
2. Using the velocity calculated in part 1, find an expression for
the heat transfer coefficient (h) and surface temperature (Ts) as a
function of distance from the leading edge (x). Graph h and Ts for
x = 1 ~ 60 cm.
3. If the length of the plate increases to 1.2 m and other
conditions (including the air properties) remain the same as in
parts 1 and 2, what is the surface temperature at the end of the
plate? Graph h and Ts for x = 0.6 ~ 1.2 m