Dear all,
I am using flat plate as well as evacuated tube solar collector. I want to
simulate the system and find out the dynamic efficiency of the collector,
not the static one. static one is energy out/energy in = m.Cp.(To-Ti) / GA.
but due to dynamic changes of solar radiation, it doesn't give good thermal
performance of the collector. so I want to find out the dynamic efficiency,
efficiency over time and tube length.
Thanking in advance.
Regards,
Mahbubul Muttakin
Mahbubul,
I am not sure what you mean by static and dynamic. It seems to me
that if you solve the energy out/energy in equation at each timestep
then plot the result, you would have the collector's dynamic efficiency
(in other words its efficiency at any "point" in time). If, however, you
integrate energy out and energy in before evaluating the equation then
you have an average (call it static) efficiency for the array over the
course of the simulation.
Perhaps you want to see the efficiency of the collector as a function
of where you are along the length of the collector? In this case, you
would need to have a noded collector model that reported the temperature
of each collector node. In this way you could calculate the efficiency
of each collector node (using the same equation but looking just at the
energy collected by and incident on each node of the collector instead
of on the collector as a whole.
Regards,
David
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David BRADLEY
Principal
Thermal Energy Systems Specialists, LLC
22 North Carroll Street - suite 370
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