Abstract
This study was expected to provide the theory references for the design of a scroll expander used in micro-compressed air energy storage (micro-CAES) systems, by conducting the computational fluid dynamics (CFD) method to obtain the pressure, velocity and temperature field distributions in the working chambers. The effects of different external expansion ratio on the transient performance of the scroll expander and the flow fields of the working chambers were investigated under a constant back-pressure. The results showed that the variable external expansion ratio has little influence on the fluctuation of the inlet mass flow rate, and the outlet mass flow rate fluctuation increases with the increase of the external expansion ratio. The heat utilization degree of the compressed air in the expander and the unsteady driving moment of the expander increase with the increase of the external expansion ratio. The secondary flow loses in the back pressure chamber also increase with the increase of the external expansion ratio. There exist obvious local high temperature areas in the back pressure chamber.
Translated title of the contribution | Unsteady flows of a scroll expander under various types of expansion process |
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Original language | Chinese (Traditional) |
Pages (from-to) | 1241-1246 |
Number of pages | 6 |
Journal | Energy Storage Science and Technology |
Volume | 8 |
Issue number | 6 |
DOIs | |
Publication status | Published - 1 Nov 2019 |