Heat Transfer Confirmation

Read something about Heat transfer modes (conduction & convection) you'll probably get your working equations there. Otherwise, ask or consult a professional mechanical engineer your question is subject for revenue and official receipt.

What were your results?

I am calculating about 18kW with an outlet temperature of 65.4'C

Is this some kind of transfer application or is it a loop process?

for now i'm not considering it to be a loop process because I need to know if I can eject more heat than I am generating on each cycle of operation.

Here are some of the values that I used:

Oil Properties

density oil: 7.37 lb/gal

Cp_oil: 1670 J/kg K

viscosity oil (70 deg) 15 cSt

k oil: 0.15 W/m K

Pr oil: 100 to 40000 (I used 10000)

Saltwater Properties (typically for 20'C)

k sw: 0.596 W/m K

viscosity sw: 1.05 * 10-6 m^2/s

B sw: 250.5* 10-6 /K

alpha sw: 1.46*10-7 m^2/s

Pr sw: 7.2

I would suggest that you compute the value of the Prandl criterion instead of making a choice which seems to be not the right one. You have all values to define Pr in your working region. I think that the choice you made leads to a too high convection factor and gives you a too high transferred power.

Pr=ρ*ν*cp/λ where ρ= specific mass (kg/m^3); ν = kinematic viscosity (m²/s); cp= specific heat (J/kg°K) and λ=conduction of oil (W/m°K). The volume unit is UK or US since the liquid gallon has different values in the 2 units systems ? This is the reason to better use units which are same everywhere and do not lead to misunderstandings. In both cases the fluid velocity is small in the pipe so that the convection coefficient is also reduced. It is possible to increase the transfer by reducing the pipe diameter since the convection coefficient grows more than the transfer area decreases so that overall the transferred power is more important. For instance a 1" pipe leads to a convection coefficient 3x bigger and the area is only half so that the transferred power is 1.5x more important.

Thanks for the post ... this is good information. This does have significant effect. Thank you.