Recent content by swguru

Trashcanman, I calculated the heat loss for a short length. For my problem the result for the first 10cm is 1.1W, calculated from (2*pi*Ksoil*(Ts-Ta))/cosh^-1(X/r). To calc the temp drop of the air, do I need now recalculate the total heat transfer coeff (ht) and then calc To from...

Gentlemen, Thanks very much for the feedback. Just getting back to the daily grind after the holiday season, so I be looking into this more over the next couple days. Happy New Year! swguru

I have an application were I have a buried air duct that has an intake air temp of 40C and I need to determine the duct length to acheive an air exit temperature of 30C(geothermal application). Based on below, do the calculations look correct? Paramaters: Pipe inside dia (ID) = .055m Buried...

Correct. I typed in D instead of L in the equation. In my experiment z=3in, D=0.5in and L=1in. Im my case z>D, but not <L, so maybe this is why the result from this calculation does not agree with FEA model and experiment results? I assumed room temperature for t2 since my soil experiment is...

Thanks. I used a similar equation for a cylinder that is buried. R=(ln(4*z/D))/2*pi*D*k) To verify calculations, I conducted a simple experiment where a resistor was placed soil. The resistor dissipated 4W. A thermocouple was attached to the resistor. After equilibrium, the resistor...

I am looking for the governing equations to calculate the conductive heat transfer in a semiinfinite solid. In my application I have a samll heat source that is buried in soil. I want to know the temperature of the soil at a given distance from the device.

Thanks all. I ended up solving by looking at resistances. Calculations aggreed well with some CFD modeling that I ran. Thanks again for the tips! Ron

I have a device that is cooled by both conduction and forced confection heat transfer. I am having trouble determiing how much heat is transfered by condcution and convection. I can easily calculate power disspated by conduction only, as well as for force convection only. How do I determine...

In review of these past threads, I did not see reference to thermal contact resitance.

I am looking for a reference that provides data on thermal contact resistance (C-m^2/W) for metal to soil interface. In my application I have an enclosure that dissipates several Watts and is buried in soil. I am aware that that values will depend highly on moisture contact and density of soil...