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Hello, I have startet to simulate a solar hot water system. I am using a CPC collector (solar thermal collectors Type 74 in TRNSYS). In this type there are many parameters that I can not find in any collector report. This parameters are listed below: Collector fin efficiency
factor: The fin efficiency
is a measure of the heat transfer from the fin to the maximum possible heat
transfer from the fin. The maximum heat transfer from the fin
would occur if the fin was uniformly at the base temperature.
Wall reflectivity: The reflectivity of the walls of the CPC collector. The reflectivity is a ratio of the reflected radiation to the toal incident radiation.
Half-acceptance angle: The half-acceptance angle of the CPC collector. The CPC collects both beam and diffuse radiation which approach the aperature within the critical angle, or half-acceptance angle.
Truncation ratio: A full CPC is one in which the walls extend upward to a height h which gives an aperature area of 1/sin(halfacceptance angle) times the absorber area. Optimal concentration is achieved in a full CPC, but a very large reflector is required. Most CPC's are truncated to some fraction of this height hbar. Truncation ratio = hbar/h
Absorptance of absorber plate: The absorptance of the absorber plate of the solar collector. The absorptance is a ratio of the amount of radiation absorbed by a surface to the total radiation incident on the surface.
Index of refraction of cover: The index of refraction of the material covering the solar collector absorber plate.
Extinction coeff. Thickness product: The product of the extinction coefficient and the thickness of one of the glazings covering the solar collector absorber plate.
Does anyone have experiences regarding to using of CPC collectors in TRNSYS? Shahrdad |