A Detailed Radiation Heat Transfer Study of a Dish-Stirling Receiver: the Impact of Cavity Wall Radiation Properties and Cavity Shapes
2015 (English)In: SOLARPACES 2015: INTERNATIONAL CONFERENCE ON CONCENTRATING SOLAR POWER AND CHEMICAL ENERGY SYSTEMS / [ed] Rajpaul, V; Richter, C, American Institute of Physics (AIP), 2015Conference paper (Refereed)
A detailed 3-D radiation analysis of a dish-Stirling cavity receiver is carried out to estimate the cavity steady-state temperatures in order to assess the receiver integrity, lifetime and efficiency performance. For this purpose, a parabolic dish was modeled with 5.2 m focal length, 8.84 m aperture diameter and 2.1 mrad typical surface error. Three generic cavity shapes (cylindrical, diamond-shaped and reverse-conical) with three different emissivities (0.2, 0.4 and 0.7) are studied. Worst-case scenario heat generations (total absorbed radiation), maximum steady-state temperatures and energy balances of the cavities are calculated to evaluate the receiver performance. The results show that reverse-conical cavities can significantly reduce cavity wall peak temperatures (by 40-120 K), improve the temperature evenness and decrease the radiation losses by 4-5%. Regarding radiation properties, low reflectivities present lower steady-state temperatures even for low/moderate direct solar fluxes. Due to the lower temperatures, lower total thermal losses are also expected.
Place, publisher, year, edition, pages
American Institute of Physics (AIP), 2015.
, AIP Conference Proceedings, ISSN 0094-243X ; 1734
IdentifiersURN: urn:nbn:se:kth:diva-183000DOI: 10.1063/1.4949069ISI: 000380374600045ISBN: 978-0-7354-1386-3OAI: oai:DiVA.org:kth-183000DiVA: diva2:906415
21st International Conference on Concentrating Solar Power and Chemical Energy Systems (SolarPACES), Cape Town, SOUTH AFRICA, OCT 13-16, 2015
QC 201608232016-02-242016-02-242016-08-23Bibliographically approved