okay hopefully the last time, the attached seems to make since.
the first page is almost straight out of my heat transfer book, i just changed the scheme around to be only in 1-D.
the second page is from wiki sites.
i believe the first page to be more accurate of an approach.
"The microwave...
The reason I am using transient and not SS is because the numbers I have calculated dont seem 100% accurate. I want to check these with calculations derived using the finite difference method. All posts have been very helpful, if I have any more questions or "hit a wall" I'll be sure to visit...
Hello,
I am a recent graduate in the field of mech eng. and I have come across a problem while trying to model the temperature distribution and heat transfer rate of a system. I will try my best to explain the situation as well as I can.
The system is fairly basic, I have a hollow concentric...
the cylinder is basically suspended(floating) because its placed on a stand in the middle of this vacuum chamber.
heat flow thru object is conduction, thats obvious, but radiation is still involved because the heater is bouncing off heat from the walls of the chamber.
the equation im using currently is
q(i) = E(bi) - J(i) / (1 - e(i) / e(i)*A(i)
and
q(i) =
sum of n surfaces with j=1 (J(i)-J(j)) / (A(i)*F(ij)^-1)
and that q= convection (till a certain pressure) + conduction(changes slighlty due to roughness and spacing with varying pressure) + radition...
corus,
i do have miniscule gaps between layers that are very difficult to determine because of the multiple layers around the cylinder.
i have used grey body radition equations(and assumptions) to figure out the net transfer of a cylinder inside a rectangle.
the problem lies in the geometries...
nope, the picture i posted is the first pic of an close model. not a scanned homework problem.
im trying to model the total heat transfer of all three transports for the system and how it changes with pressure.
I know that in a vacuum, radiation and conduction are the main transports for heat and that convention plays a small role.
I was trying to determine if thermal energy transfered (mostly conduction) throughout my system is effected by pressue. Knowing that convective heat transfer is pressure...
Hello,
Here is my situation:
A hollow multi layed concentric cylinder that is placed inside a vacuum. There is a heating element in the middle of the cylinder.
Temp initial is room temp and the pressure initial is atm.
Temp is increased to 350 degs C. Pressure is reduced to about 40...
