Interpretation of software heat transfer results

[jakub123]

Hello!
I am n new user, probably like others I've experienced some problems so I'm here to ask for help (I'am Pole so please forgive me some grammar mistakes)

The case is as follow:
I am using very simple software 1D which predicts the heat flux through the boundaries of pipe. Within the pipe I have a gas and the outer surface is in thermal contact with external source of heat. The case is solved numerically and the gas/pipe/source is discretized both spatially and time dependent. The reason why time dependent is that the gas is flowing through the pipe back and forth in sinusoidal manner. The output from every discrete point is interpolated by fourier series. So I have some fuction that describes instantaneous changes in heat flux from whole domain. Now I want to answer the question: what amount of heat shold I supply to heating fluid outside the pipe.

It seems simple, but it not because:
The output fuction is expressed in terms of Watts [J/s] so I have answer what amount of heat should I supply for ONE second, but the cycle of gas flow inside the pipe takes 0,2 sec. Moreover the solution prsent values that are the sum of heat fluxes through the domain in one time step. So if the output whisch have sinusoidal form indicate that the maximum of heat absorption (in the numerical simulation) is 1500[W] per cycle, shuld I have to supply to fluid exactly, more than that or less? I afraid that the peak value of heat need to be supply is hidden and I cant interprete this solution.

I would be grateful for your help.
Regards,
Jakub

 

[IRstuff]

Is this for school? Student posting is not allowed.

TTFN
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[jakub123]

No.

I afraid that the way of asking my question is not sufficient enough. But the problem is that I should make a long introduction about the way of how the iterative solver of code that I use accounts all the heat fluxes thorough the entire domain, it uses the simple integration, and it's based on the assumption that div(q)=0 there is no heat sources within domain. The total amount of heat fluxes is then time averaged to give the final result in terms of fouries series. But the way of heat transient phenomenas it's quite bitchy to account, so is always is averaged. The problem is that I don't kon how to extract the instanteneus values which would suggest that my heat sources, is not enough. Maybe the average value is correct, but in some instanec it would require to add more heat energy to the heat sources.