Description of the Specific Test and Test Procedure
Within EN 12975-2, the following tests and calculation procedures are concerned with discontinuous efficiency curves of polymeric collectors with temperature limiting measures, such as thermotropic layers, temperature-controlled ventilation, or other active or passive measures.
In the following chapters of EN12975 second-order dependencies on the temperature difference (tm — ta) (tm: middle temperature of the fluid in the collector, ta: ambient temperature) are established (Table 18.3).
A simple linear dependency on this temperature difference is established in Chapter C.2 [Determination of stagnation temperature; Formula (C.1)].
Table 18.3 Chapters of EN12975 for which second-order dependencies on the temperature difference are established.