Aha! I believe I've figured this out. I did oversimplify it in my initial attempt, and MintJulep was trying to point me in the right direction even if it wasn't clear to me how that impacted my missing variables.
So I must first solve for q based on the airstream temperature and the ambient...
Thanks, I did know that there is also some convection and radiation involved, but I thought I'd try a simpler check first, as I assumed (possibly incorrectly) that much of the heat transfer will occur through conduction. But even if I include convection and radiation, I believe I'll still have...
I'm attempting to calculate the insulation required for condensation control on an insulated duct (material is duct board) in a ventilated attic space (essentially outdoors). I'm using the ASHRAE formula for One-Dimensional Steady-State Conduction from the Fundamentals Handbook (Chapter 4)...
Domestic water heating sizing is a somewhat inexact science. You are looking to estimate the peak water usage for a system, which can vary for any specific application, even for similar building types. There are solid rules of thumb and empirical data available though, the best are available...