Performance data for a single panel cannot be applied directly to a series of connected panels if the flow rate through the series is the same as for the single panel test data. If, however, N panels of the same type are connected in series and the flow is N times that of the single panel flow used during the testing, then the single panel performance data can be applied. If two panels are considered connected in series and the flow rate is set to a single panel test flow, the performance will be less than if the two panels were connected in parallel with the same flow rate through each collector. The useful energy output from the two collectors connected in series is then given by (Morrison, 2001):
Qu = Ac Fr [(toOG - Ul (T - Ta) + (ra)Gr - Ul (Tol - Ta)]
where To1 = outlet temperature from first collector given by
Eliminating To1 from Eqs. (4.19) and (4.20) gives
where FR1, UL1, and (ia)1 are the factors for the single panel tested, and K is
Was this article helpful?
Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.