Dear Experts,
Currently working on a project to simulate an absorption chiller fed from a solar collector.
For the solar collector I am using type 71(ETC) of 42m2 collector area. Also attached the SRCC test certificate for the same. Problem is I am getting unacceptable high Outlet fluid temperatures eg. Tin=60 Tou=150 @ flow rate=250. Same is the case if I use test data from the Keymark test and further the outputs do not match with the outputs for the SRCC data.
Please could you advise if the parameters are specified correctly and the assumptions mentioned are in line with what is required by TRNSYS. Assuming TRNSYS uses gross areas and average temperatures.
1. Number in series 5 -
(Solar array design calculated for required flow and outlet temp)
2. Collector area 42 m^2
(Total gross collector array area, Trnsys will internally calculate nos in parallel)
3. Fluid specific heat 4.190 kJ/kg.K (water)
4. Efficiency mode 2 - (Tavg based on SRCC ISO efficiency equation note (P)=Ti-Ta)
5. Flow rate at test conditions 71.64 kg/hr.m^2 (SRCC Test mass flow rate .0199*3600-assumption is it is based on gross area and not aperture area )
6. Intercept efficiency 0.398 - (SRCC ISO eff. equation- SI units η= 0.398 - 0.62210(P/G) - 0.01611(P²/G). However solar keymark test data mentions 0.734)
7. Negative of first order efficiency coefficient 2.24 kJ/hr.m^2.K (SRCC .6221*3.6. However, solar keymar test data mentions 5.5044 )
8. Negative of second order efficiency coefficient 0.058 kJ/hr.m^2.K^2 (SRCC .01611*3.6. However, solar keymark test data mentions 0.0166 )
9. Logical unit of file containing biaxial IAM data 37 - (TRNSYS assigned)
10. Number of longitudinal angles for which IAMs are provided 11 - (external data file prepared as per SRCC data)
11. Number of transverse angles for which IAMs are provided 11 - (external data file prepared as per SRCC data)
Thank you for your time in advance.
Regards,
Janeet