Hi Veber,
The heat loss equations are described in Sections 2.1.1 and 2.4.2 of the physical trough model reference manual. For example, see Equations 2.11, 2.26, 2.57, and 2.58 and their descriptions. Additional heat losses are described in Table 8.
Wagner, M. J.; Gilman, P. (2011). Technical Manual for the SAM Physical Trough Model. 124 pp.; NREL Report No. TP-5500-51825. (
PDF 3.7 MB
)
References to this and other papers on SAM's CSP model are on the CSP Publications page:
sam.nrel.gov/concentrating-solar-power/csp-publications.html.
Best regards,
Paul.