ライブラリ登録: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-474-8

ISBN Online: 978-1-56700-473-1

International Heat Transfer Conference 16
August, 10-15, 2018, Beijing, China

EXPERIMENTAL TESTING OF A SMALL-SCALE SOLAR THERMAL BRAYTON CYCLE RECUPERATOR

Get access (open in a dialog) DOI: 10.1615/IHTC16.her.023587
pages 4815-4822

要約

The open Brayton cycle with open cavity receiver utilises a parabolic dish to concentrate solar irradiance so that it may be captured by the working fluid (air). The cycle has been analysed and optimised to work with a simple receiver so that complexity and cost may be reduced. To maintain sufficient cycle effectiveness, a large efficient recuperator has to be implemented to allow for the high temperatures in order of 1000 K needed by the Brayton cycle. The proposed micro-turbine, an automotive turbocharger, cannot operate at high pressure ratios. The recuperator allows for lower pressure ratios to be considered. The purpose of this research is to test a design for a low-pressure and high-temperature recuperator that can be implemented within the solar Brayton cycle, and can be locally manufactured for a relatively low cost, as no current solution for such a cycle exists. Current solutions involve complex designs, expensive manufacturing processes and permanent joining methods that would eliminate the possibility for inspection and maintenance. The key element in the proposed design would see a high temperature sealant being used along with a clamped plate heat exchanger layout, in place of welding, allowing for ease of assembly as well as the ability to dismantle the unit for inspection. To ascertain the possibility of implementing the design, the recuperator was first modelled and shown to adhere to the necessary criteria. Results from the theoretical model show that at the proposed cycle conditions the recuperator plate bank would consist of 350 channels with an effectiveness of 90% and a total pressure drop of 3.49 kPa. A small scale model of the recuperator was constructed and tested, using both in-stream and surface thermocouples. Due to combustion issues with the LPG, the data was slightly skewed, however enough results were attained to show that the design could prove effective with a few modifications and further testing, and that the high temperature sealant works well with the clamped plate design.