Recent content by Indychus

Thanks for all of the help guys, I think I've got this figured out. I found the engineering toolbox chart earlier today, but was hesitant to use the 1 since I find it hard to believe that a painted surface has the same emissivity as a total black body. I found another resource that claims the...

The number does not have to be exact, a ballpark will work. Just wanting confirmation that I am approaching this the right way. Do I have to consider both the emissivity of the paint AND the underlying material?

Well thanks for the input :) I'm pretty sure i can calculate the Qin and use the emissivity coefficient to modify it based on color and material, but I'd like a confirmation of that from someone who knows more about the subject than myself. Hopefully someone will chime in.

Would it be correct to use the surface's emissivity coefficient? Where can I find emissivity values for different colors?

That's very interesting with the trash bag, I have never considered that! Basically, i am designing an A/C system for a small vehicle. I am trying to calculate Qin through the various surfaces, i.e. windows, roof, etc. I have no idea how to take color into account for the qin through the roof.

Hey, I am working on a thermodynamic design problem, and am trying to come up with some coefficients to modify Qin through a metal surface that is painted different colors. I know that there would be a significant difference in heat through the surface if it were black as opposed to a...

Homework Statement Say we have a warehouse with a 5 hr time constant. The outside temp is 16C at 2:00AM, and 32C at 2:00PM. The warehouse is at 24C at noon. What will the temp be at 6:00 pm? When will the temp be 27C? The Attempt at a Solution First, I set up a sine wave for the...

Thanks for the quick responses guys, I've got a handle on it now. I'll probably be back in an hour or so with a heating/cooling problem though, so bear with me :)

Wow, haha, such a simple mistake has eluded me for the better part of an hour. Thanks!

They just solved for c, then multiplied through by 2 to eliminate the 1/2's.

I know you guys must get tired of the tank problem, but I just can't seem to get this figured out. This is my first post here, so hopefully this is in the right subforum and is presented properly. "A brine solution of salt flows at a constant rate of 4L/min into a large tank that initially...